Patrick laughrey when you do fix your truck please take it back to him and let him (danner) check it again. I have the same truck with the same broken bolt in the same place but I am getting higher ltft on bank one and yes my engine exhaust leak goes away when the engine is warmed up and my ltft on bank one goes down from 25 to 14. now this video explains a lot of what could be go in on with my problem.
I hope this is helpful but there’s an equation I use that seems to be relatively accurate to figure out what the maf reading should be. The displacement should equal maf reading at 600 rpms. So when you multiply actual rpms by engine displacement and then divide by 600 that should be your MAF reading and I’ve found you can have about a 15% difference that will still allow the appropriate functionality. So for example rpms are at 1595 on a 6.0 it would look like this 1595X6.0=9576, 9576/600= 15.96. And through my own trial and error anything within a couple g/s off idle is ok and at idle it should be pretty close. Edited for grammar
Great Job Fellas! The joy of chasing multiple and possibly cumulative problems, but yet still able to identify the issues individually using proven methods and logic! Awesome Video Danner's!
ScannerDanner you are correct. GM injector balance test specs are to calculate the average pressure drop. all injectors must be within +/- 1.5psi of the average. anything outside of that should be replaced
love Caleb's responses of " lets do that! " when you mentioned going inside because its cold and needing to take it for a test drive, obviously with the heater on. Items I've come to realise you need is clipboard with paper and pen, car charger for all your electronics you carry. 😬
You are a legend in electronic automotive and electronics is difficult to explain because it is not visual like brakes and rotors keep up the good work
I have a 2000 Silverado 2500 with 6.0 had the fuel pump replaced. Then last year. I was having trouble with it. It had no power. And wouldn't go. I do construction. My dad is a retired old school mechanic. But I got a scanner with live feed. And watching your videos. And class room videos. You help me fix it. I traced it back to a fuel problem. But was unsure. Cause the fuel pump was replaced. After weeks of your tests and tricks. I was left with replacing the fuel pump. And I got ready to drop the tank. I found the problem. The filler neck rusted away. And I was getting rain water. And road salt in the fuel. All last winter. I live in Ohio. Near PA. So lots of road salt. I replaced all 4 of the O2 sensors with bocsh. Had a one that failed from day one. So I replaced all 4 with a/c Delco. And it's been great ever since. The first fuel pump. I let the deal install. cost me $900. Did the new pump last year myself. Was about 300. Plus a OBD2 scanner with live feed from Walmart. I'm looking at a 02 Silverado 2500hd with a 6.6 turbo Duramax. Low mileage. Do you do any diesel videos? Or your bother? Thanks for the help. And teaching with your videos!!! Very helpful. Tip tricks. And more. I tell everyone I know. To check out your videos!!!!👍👍👍👍
you didn't notice the gas smell or had it pouring on the ground when re-fueling...... typical GM truck thing, filler neck rusted through and/or the clamps rusted off
@@throttlebottle5906 no it was rusted away on the top part. So no leaking fuel. And the truck has a vent line. Near the rear of the cab(ext cab on mine. So the return line vents there so you smell gas sometimes. But not all the time. I reached up to take the hose clamp. Off the rubber hose to the filler neck. As I felt my hand up to find the screw head. I could feel it was broken off. It was probably it's last day. I just got a new pump. So lucky. With all my test from the videos. I had the new pump. I was saying to myself for months. It can't be the pump. It's new. The dealer used a Delphi pump. I'm good friends. With the owner of the dealership. I bought the truck there. Two years earlier. So I knew he did everything right. I put in a new Delphi pump. Took the filter off the old one. It was full of road salt. And covered in salt. I noticed. It was bad and ran extra rough on rainy days. It was January at the time. I did several fuel pressure tests. Check my intake sensor etc. The videos really help me understand fuel trim. And how to diagnose. The problem. Without replacing. Unnecessary parts!!!!
@@throttlebottle5906 it's was the filler neck at the clamp. That's the only part I didn't have. I ordered one. But to get to work. I too a sheet of aluminum siding coil. And maid a sleeve. Screwed and sealed it to the fill neck. ( What was left of it.) Then put the hose and clamp on. After doing the new pump.
If Snap On engineers watch this episode then is good to improve his scanner... SO, on that injectors test balance is good to have some windows to made notes!? eg. Starting test pressure, drop pressure and differences between pressures (indeed, differences between pressures be calculated automatically) for each one injector.
Reason for the differences in the ending pressure on each test (each test meaning after all eight (8) cylinders) is because the diagnostic computer randomly chooses how long the injector test should run. Like the first (1st) test you completed, each injector was tested for approximately 3.0 seconds (with me guessing the length). And as for the third (3rd) injector test, lasted for approximately 3.4 seconds... The ECU tells the injector to pulse at a given rate for a fixed amount of time. The amount of time is different each time you run the injector test.... Anyhow, I love how you explained the test overall, it made sense. Some people can't seem to make simple things understandable... As for the fuel pressure drop on the load test, your absolutely correct, it's not supposed to drop any. My guess is like yours, fuel pump related. It's also possible that the fuel pressure regulator is failing, or leaking injectors as you stated also... Not sure if the guy got this all fixed or not, I haven't gone through all the comments yet... But this is the second (2nd) video I've watched of yours, and I have subscribed to your channel, and will continue to watch more. Your very knowledgeable in the diagnostic's which I am always wanting to take in more knowledge any way I can. Keep up the awesome work and Happy New Year!
I've been playing catch up with your videos but don't usually comment, especially on the older ones just because I feel like it's long passed and no one will see it anyway. But, I have to tell you, I loved this case study! You may have not gotten the repair but it's clear to see what you were saying and I absolutely agree. The pump is junk for starters, should never see fuel pressure drop like that under load, and the injector balance test was also cut and dry. Balance test is just that, a balance test! Injectors should all be within the same range not 2+ lbs plus or minus of each other, that is off balance, a pound plus or minus a touch, ok. I thought you showed a lot of great procedures while clearly explaining the thought process . Also, that exhaust leak has No bearing on the condition present IMO. Sorry for the long message, and I wasn't going to comment! 😂 May God bless, heal, and protect your family always! Peace.
Had similar issue with 03 250 super duty after several dead ends removed gas tank and powered fuel pump with power probe right at the fuel pump out let there was some rubber bushing oring that was leaking in the tank spraying straight down and not holding pressure could not find seal so bought assembly it’s been fine ever since
I had a problem on my truck and I've been watching your videos lately and found out the injector was bad keep up the good work man 👍 u saved me big time
Hey Paul, thanks for another good vid! I could write a book on the painful journey of finding you channel lol. Im a plumber by trade but have been forced to learn the auto tec world, due to an epidemic of parts changers down here in Perth, Western Australia. I have two beautiful pain in the arse vehicles that make for great case studies that relate to this overlapping multiple problems vid. that will keep me busy learning for a lifetime! Thanks again for the wealth of knowledge in this very technical field of trouble shooting! Think its time for SD to take the show on the road, load the RV and do a lap of Aus. Mate happy to chuck a shrimp on the barby for you anytime!!
Keep it up Paul, I keep watching you guys for different ways to approach different problems and the little I see i feel like these techniques hit the spot, I really wish you were my teacher when I was starting the trade I’m not a fan of replacing parts. I watch all your videos and I rewatch them over and over to see if I missed something, your way of teaching has taught me so much
This was a bewilderinging video. I slogged thru all 1.13.55 of it. Kudos to Caleb. It made me want to throw the parts cannon on these issues with my own silverado. There was no adequate explanation for the negative long term fuel trims. Really-a bad injector is issuing too little or too much fuel but this did not correlate with the misfiring cylinders or with the so-called abnormal injector balance results. The very slight variations in the injector balance test can be explained by the hysteresis effect on the mechanics of the MAC mechanical transducer and its attendant gauge.The check engine light, which is the vexation of those of us who want to get our vehicles legally inspected is a bunch of bull and that the auto makers set the"money light" with minimal problematic parameters. I do appreciate your teaching.
yeah, I wasn't happy with the injector flow test results either but absolutely showed the lean condition and low power/misfire complaints under load being caused by low fuel pressure. I wanted to work further with the owner and he even was commenting on here but then he went silent on me. I think in large part because my brother found that the frame was bad on this truck, so I don't blame the owner for saying "forget it, I'm done".
Ive seen the fuel pressure regulator leak gasoline through the fuel regulator vacuum port, causing the fuel trims go rich, and misfire because of fuel been sucked into the intake. Usually when the fuel pressure regulator is bad, it will cause a hard start because of the loss of fuel pressure leaking out from the fuel pressure regulator into intake. Didn't see the truck have that issue, "hard starting". Good video scanner danner!
scanner danner , thankns 1,000,000 ! great video . you n caleb will be hearing from me , i've been chasing a p0300 on a express 3500 for months now, (3 parts - cannon repairs, still no fix...) i've got 2 months of actron freeze frame and live data..
He could have a leakage in the fuel pump module,like one of the hoses...I’ve seen that before. Great video,love to follow your step by step thought process! 👍
Paul, for the pressure drop test on the injectors, why not hook up the wps500 and pico and get an exact record of the different pressure drops? quick, easy, accurate, and a graphed record.
This Video contained very valuable information even if you didn't solve the problem. I learn many things from you . Thank you, Mr. ScannerDanner Your student Hussain Alsalman From Saudi Arabia
Hi sir , You have to open all injectors and test them by the injectors tester ( test for leak) to be sure that the problem is with the fuel issue. Best regards. I am very like you and watch maybe all of your videos. I am engineer Ali from Iraq / baghdad Thanks for learning 🌹🌹
I fixed my misfires and all the lights that come with it!! Stability traction control, reduce engine!! I changed air filter regapped plugs and dumped 1 gallon of laquar thinner with ten gallons of gas and a bottle of Lucas fuel injector cleaner in tank ran till empty,, all good so then I fully replaced plugs gapped/tourqued to spec!! Bacically it had a clogged 3 injector causing fualing plugs creating bad fuel ratio!! Dirtying Tb!!
At 12:20 under the "Fuel tank pressure sensor (V)", it showed constantly 0V. I was surprised that you didn't comment on that, besides that you've mentioned that it never changed. And still you're questioned "Why is the tank pressure sensor isn't even plugged in? How was I getting tank pressure before?". It's incredible that even diagnosticians made so tiny mistakes (me the first). Have a nice week-end by the way!
I just didn't really care all that much which was why I moved away from it. I only wanted that data PID for a quick test of the purge valve. Once I verified a good purge valve, I no longer cared. Make sense? It's just part of the EVAP system and was no longer relevant to the rich condition. (After the purge valve proved good)
You know you can chase your tail around forever if you have bad ground and power + at the source (battery) Even if it’s not Every car needs it and will benefit from it and It’s definitely a good place to start and you will fix very weird things that you could never find I recommend to use anti seize compound to keep the corrosion away from happening in future and razor blade the metal and remove paint under the connector And you are working with a known proper baseline from battery to every component and computer and ecu
I've seen injectors change like these had. My Wife's Buick V6 did the same thing, until I let it sit for a while. Then the really bad one shows its reading and two others were iffy at best. Replaced them with new GM injectors and O'Rings. Problem solved.
Being a GM dealer driveability tech u have a weird one. I’d be going after leaking regulator or flooded evap cannister but looks like u did that, vehicles to old to have 08+ fuel composition algorithm feature. 6.6 g/s seems high, I’d be looking at excess skewed maf reading, aftermarket air filter or possible out of spec injectors swapped from a out of spec 6.0 liter vehicle to a 5.3 vehicle. All I suggested is still very rare and will cause lean codes not rich codes 95% of time. 55 psi seems kinda high from my memory. Possibly find a to disable to fuel pump and run a manual cylinder tool fuel system, to 45 psi at idle and see if fuel trims improve.
I am waiting to here back from the owner about the injectors he replaced. The fuel psi spec on this one is 48-54, so it was in spec (not under load of course). I'm with you on the possibility of a skewed MAF and I should have looked in front of the MAF too. Also, I never checked for fuel contaminated oil. Something else to look at after I hear back from the customer about the injectors. Thanks for the reply!
@@ScannerDanner , is it a Flex Fuel Vehicle? What does the alcohol percentage PID read ? Can you do a Fuel Alcohol Content reset with the Verus? If not a DS708 or MaxiSys should be able to reset it.
👍to all of you asking Scanner Danner (Paul) questions about your personal vehicle problems, STOP IT! HIS TIME IS VALUABLE AND NOT FREE! We are thousands of viewers to one man. That's disrespectful and inconsiderate. Sorry for your troubles, but join the premium site. I am so impressed that he actually took time to answer some of the person questions. Cudoes to you Paul and your big heart!
Thanks James! I don't mind most of them. The ones I never repond to are those who've done no testing. For example: "My car doesn't start, what do you think it could be?" No year, make or model given, no direction whatsoever. I just keep scrolling! As a comparison: "My (insert year, make and model) doesn't start, and I've confirmed spark but no injection pulse, can you give me some direction"? Now we're taking! I'm answering 🙂
@@ScannerDanner That's really kind of you my friend. I wouldn't feel right about doing it without giving back somehow. Your knowledge and wisdom is hard earned I'm sure. Don't know how you find time for it all. I'm a machine shop instructor and a wannabe mechanic. Really admire your teaching and tech skills, ethics, and big heart. World could use more Danners IMO🙂Thanks for sharing. Do my best to keep supporting you as I am able. Best Paul!
If it's a Flex Fuel Vehicle (and I'm absolutely certain that it has no E85 in tank) I would just start off doing a Fuel Alcohol Content Reset. It Fixed the P0172 and the negative fuel trims on a 2009 Impala I had today
So it doesn't start too well either? You're right, the pump definitely seems bad. I'm less convinced about the injectors though. Been down that road myself with a ford. Replaced all the injectors and it turned out to be an internal intermittent break/open on a couple brand new oem motorcraft sparkplugs. They were bad right out of the box. Problem always got worse when hot so I assumed the injectors were leaking but I was wrong. Edit: I am not implying this is your problem.
God Bless you Paul...you are a great man! I hope you are doing well my friend! Great info on MAF g/s numbers at idle! I have definitely seen them report higher than expected and have concluded that this can very well be normal for a smaller Liter engine...why is that? Excellent video...as always!
I would like to know why as well. Maybe smaller engines= slightly higher idle to maintain a smooth idle?? = higher grams/s. Just a thought. Any other theories out there?
I believe the response curve of the MAF analog/digital converter in the ECU / ECM is not perfectly linear and may induce some false / under /over reading at low RPM. Same as in temperature reading in the lower scale... were GM displays LO until temp reach a certain value....
And also... for MAF... until engine goes in closed loop, the ECM uses preset values from tables based on TPS, RPM and .... CTS... Coolant Temperature Sensor and also from AIT Air Intake Temp Sensor.... if one or both of these 2 are faulty...this can result in faulty calculation by the ECU/ECM..... Think of it....
Finally.... on my old 1989 GM C4 Corvette.... when a problem like this one occurs I always verify at first the parameters of the equation determining the pulse width of the injectors.... that is ...the sensors including the knock sensor! Sure... when using a fuel pressure drop test tool .... engine not running... I can eliminate (or not) the faulty injectors.... but not the knocks and leaks caused by a missing bolt on an exhaust manifold ... with regard to the O2 sensor.... may be this could be a hint.... love your videos! ...Wish I could be closer to attend your course!
Brother Danner is the MVP of this vid. You almost had to change your screen name to SCANNER-LESS DANNER. Did bro have an extra set of undies for ya too? I know i would need them. I almost had a coronary a couple days ago when my brand new Autel Maxisys Elite got bumped and nearly fell. Looked alot like the great escape your scanner tried to make (have had the scanner a month). I dont worry about my Snap On scanner, it has a cord (Solus Ultra). EDIT: Something i noticed, even with snow on the ground, shouldnt that LS engine be running at 210 Fahrenheit? Thats the normal number i see on a near daily basis. I am suprised you didnt do your fuel pressure test with the WPS500x. You could do the simple pressure checks, then shorten your time base and look at the actual injector operation under load, Cursor your peaks and the lean condition would have jumped up and slapped you in the face. I use my cheap home made transducer like that sometimes, and it has helped me diagnose an intermittent injector. (Watching your vids since 2013_ish is what got me rolling on the scope thing, its all your fault)
Another great video, trying to catch up so I can be watching the more current ones. Learning so much about cars from watching your videos. I think my next tool is going to be the Picoscope.
I am always interested to see the pulse with modulation waveforms on the scope to see how long they are open I saw 3.2 milliseconds on your scanner to see if it's a load unloading it down or I can use a fluke meter with a duty cycle to tell me how long waveforms are the best thanks for the comment paul
Fuel tank pressure change? Temp gun on each exhaust pipe? Plug gap smashed? Fuel contamination? Oiled air filter has caused the maf to crap out on me and cause this issue as well. That exhaust leak is killing it for you in determining any kind of un-metered air causing it to run lean and then causing it to compensate as a rich issue.
thanks for video.i think problem with that truck is low compression on those two cylinder with misfire.i run into same problem. i think bad MAF and fuel pump will affect all cylinders.
370k miles on my 2004 GM original injectors never cleaned runs perfectly... I got 170k out of a Delphi pump... excellent Airtex junk pump? Excellent work Thanks
Was a pump from advanced auto cant remember the brand found out after I just talked to the former owner that he replaced the fuel lines maybe he kinked them when he installed them haven't checked yet
@@patricklaughrey8727 airtex not to good last two years. Maybe kinked lines. Excellent tech Danner. I have a few of those trucks excellent reliable rigs 6.0 GM trucks.
@@SuperScopeLLC maybe air bubbles in fuel stream or loose output on pump? I do alot of diesel gas industrial since 1978 . Had one new crane run terrible was a air leak in fitting on ISx common rail. Noisy vibration from electric pump a clue also. Ford had diesel fuel steel tanks corroded galvanized surface inside tanks in 2001 filling pump with sand like debris. Changed many to plastic tanks. Excellent work Thanks!
Another PS: a check for engine oil contaminated by fuel or something else (ie on car injector cleaning fluid) that has passed the piston rings might also not go astray, have had that scenario cause negative trims at idle on multiple vehicles.
Oscillations in the pump current waveform might be from the system voltage changing as other loads are turning on and off. Remember the PCM is watching system voltage and modifying the injector pulse. If it sees a lower system voltage it will make changes to the injector pulse width to compensate for the pump slowing down.
@@romellabiche175 The fuel pump runs 100% on this vehicle. It uses a return system. The PCM turns on a relay to supply power to the pump. There is no module to control the speed of the fuel pump.
I like using the pressure transducer on the fuel rail when i do that test and then put the verus in split screen mode so its all on the same screen then you can screen shot each cylinder test to have in your records for later review if needed. Just a idea to try cause you'll have the test recorded in your records. Just make sure there's enough time on the scope to record the whole test on one screen. I also do the same thing with the split screen and my VE calculator and scan data right on the same screen on the Verus. I pin the VE calculator right to the task bar so i can pull it up when ever i need it. Just some ideas that i like doing!!
sorry it was so long, but there were a lot of good testing methods and techniques shown. It is about the journey anyway in my opinion. But I understand you guys wanting a solid conclusion. We had it with the pump, just not with the negative trims
Great video, Paul! I can't wait to hear the outcome. Although I am sure that it is going to be fixed. After having a couple toyota corollas kick my butt with lean codes, I started using the WPS to check fuel pressure while doing injector balance tests because its more accurate, and records the values for me on the scope. I like the WPS because it's a lot easier to see .5 psi increments, at least for me.
I totally agree with you on that too PJ..Looking at a dial sometimes can be deceiving. Love the video you did demonstrating how you perform that test. Good stuff bro.! 😃👍
Lol PJ. With Paul saying "was it this value or that value" I was thinking, throw the Pico on it. 2 Reasons. A.... Accuracy of reading and B...Proof for the customer as to why injectors are a suspected problem. Scope not needed all the time but on something with possible multiple issues all the evidence can be presented to the customer.
Exmotorsports yeah, that Yaris video is probably my favorite, and probably most helpful. Lol I see so many people getting beat up by those lean codes, including myself until i figured out a good solid diagnostic test.
@@ScannerDanner We've all had those missed opportunities before. I'm hoping next year will be much better for me on that hindsight issue since it will be 2020. 😂👍 Sometimes it's the matter of convenience. Easier to plug a gauge in than drag everything out for the Pico. Especially in the cold. I saw the snow on the bushes there in the background. Brrr. Lol. Cheers Brother.!
I’m having a similar issue with my Subaru sti... since it’s a flat 4 cylinder, there is only one bank. In the Subaru world, AF learning 1 is LTFT, AF correction 1 is stft. As of now, my MAF is reading high at idle 4.5ish g/sec at idle. My AF learning 1 in CL in the low load table is -5.69, with stft sitting at 0. Once I get into load, still In closed loop, my LTFT are normal +.78 or so. Car has misfires on all four cylinders, maybe 1-2 roughness, at most I’ve seen up to 3 misfires. My Wideband is reporting 14.59, but it’s like it’s fighting to stay stoich. I have a aftermarket FPR and FPS. I can log and monitor fuel pressure diff compensations, and I’m seeing a correction of about 10 psi at idle, but under load it’s spot on. Sorry for the long post. Thanks Paul, curious on what you think. I cleaned the MAF completely once again, o ring is on it, and no leaks. Subaru wanted almost 300 dollars for a new MAF sensor. I’m most likely just going to convert my car over to speed density.. but still trying to diagnose what’s going on with my car now. I do run pump flex fuel, with an ethanol safe fuel pump.
ScannerDanner I have an aftermarket FPR and FP sensor. What’s neat is I can monitor fuel pressure diff comp. my base fuel pressure is 43.5, same as stock. I wonder since I run flex fuel, if there is a different amount of oxygen Readings depending on the ethanol content variations
Great video. Should be interesting to see if is a pump problem. I've had a few new bad ones right out of the box. It might be worth trying to clean the injectors first before replacing them. On these returnless systems, I've run into injectors with a white sediment restricting the screens due to the crappy gas we're stuck with now.My understanding is that it's from the alcohol in it. I'm surprised that you weren't getting a code for the fuel tank pressure sensor being unplugged.When you went back to check the pump, the first thing I noticed was that the sensor was unplugged. I usually take a look at what drive cycles have been completed. It's a pain when somebody clears the codes & you lose what would be some helpful freeze frame data.
I Wouldn't Try a Injector Balance Test with a Bad Fuel Pump. To me it's a Invalid Test. & 2 psi Differance Isn't enough for Me to Chasing Injector Problem. It Could Possably Be Rich Because the Computer Trying To compasate For Lean Condition. So I'd Recommend Fuel Pump & Filter Than Repair Exhaust Leak. Than see how it Runs.
Hi Paul. On the topic, more than once after replacing stuck injectors, I pull out the oil dipstick and it smells of gasoline. After changing the oil, LT fuel trim returns to normal.
I ALWAYS look forward to your videos. You are the best at laying out and describing your diagnostic thought process. This one was interesting; both rich and lean. Thank you for sharing.
I laughed at Danner saying to you after you told him you'd switch the PowerProbes ( 59:18 ): "I don't have anything good here!" Sounds just like me ... because over here, that's the truth! 😁 Seems every GM truck has this problem in one form or another. My own '07 1500 with the 5.3 has borderline rich-code fuel trims, too (I've seen it as bad as -16 on one bank briefly, but seems to waver between -7 & -12). Also hasn't run a couple monitors in over 2 years now. Been driving with the rejected sticker, since I haven't figured out how to get paid working on my own junk yet ... 😂 Eric O. over at SMA said it's more than likely a lazy t-stat in my case, based on what I told him. By now, there's probably more things failing - that was quite a while ago. This was great to watch, since now I have a game plan should I ever decide to start troubleshooting this toilet, lol. I've already replaced the entire rear carrier at 97k - had chunks missing from the tips of the spiders, and the carrier itself was BIG TIME sloppy. They just don't build 'em like they used to. Keeps us employed at least ... but sucks when you have to fix your own crap! Anyway, you, Caleb, James, and the rest of the family have yourselves a very Merry Christmas, and a Happy, Prosperous New Year. May God continue to bless you, my friend.
The amperage draw scope test results make me wonder again about "proving circuit integrity by watching amp draw" that you state on some fuel pump videos. The draw was close to the same with the marginal ground. If you ever get a pump with a worse connection, I'd like to see video on amp draw differences. Like you say, your truck pulls 9+ amps, this one pulls 7 amps. It would be tough to call good connections without knowing what to expect. I posted the question on premium channel too but haven't seen an answer I like yet. Thanks.
I don't know that I have one you will like. It is just another test we use as a guide. We can always back it up with a voltage measurement at the pump connector when possible. Thanks Bart!!
Just a thought with the fuel tank pressure sensor unplugged, if that could be the cause of the rich condition due to the computer commanding an excessively long purge waiting for the tank pressure to change??? Remember there was no stored fault codes for the unplugged FTPS and of course was unplugged when the Rich codes were set because all the freeze frame data showed 0v for the FTPS voltage.
@@ScannerDanner Misses at certain times at idle and then runs better when I put seafoam in the gas, changed plugs wires fuel filter did a clean on the maf new o2's check for vacuum leaks
I’m having the exact same issue with a equinox, I’m to the point where I’m starting to think the cats are semi plugged up, someone at some point replaced intake, manifold gaskets. I did the exact same injector balance test and had basically the same results. However, I pulled the fuel rail with the injectors and did the test. I found that when somebody had replaced intake gaskets and reconnected each injector they had injector harness wired to the wrong injectors that was causing my misfire and Rich condition which intern I think started to plug up the catalytic converter with restriction to the catalytic converter. Wouldn’t that caused negative fuel trim numbers because of the ECM trying to pull fuel out of the fuel trim?
great video this explained a lot of what could be going on with my exact same truck, broken exhaust bolt, and location also the change in my long term fuel trims when warmed up Going from 25 to 14. not good. but great video.
Couldn't a faulty/leaking FPR cause the rich condition as well as the low fuel pressure? This is a situation where a FP flow test off the return line would have been interesting just to confirm/demonstrate the FP diagnosis. Do you purge the air from the fuel pressure gauge line before the injector test? Diagnostics can get tricky on vehicles with multiple issues like that.
#1 yes, no fuel came from the reg vacuum port (forgot to mention that) #2 good psi but drops under load would not be from a stuck open regulator. It would have been low all the time #3 yes I did, a few times on this one for this very concern
How are you Mr. Danner? Quick question? With the MAF sensor you’re talking about, 6L should be around 6, a 5L should be around 5G/ps, what would be normal for a smaller engine? Say a 2.4 Liter naturally aspirated.
Volume from the pump isn't in the equation during the injector drop test, it tests the pressure drop caused by each injector using line pressure only, the pump only activates during the prime between each injector activation and doesn't run while the injectors are being activated.
Ps. I think I hear an exhaust leak there with the engine running, fuel trim readings could be skewed if that is before any of the 02 sensors, just a thought on a variable 👍 Edit: You did mention the exhaust leak, I just missed that part.
Has a good visual inspection been performed on the fuel line? Maybe fuel line dented during body lift? Flow restriction could also maybe explain injector imbalance?
Have had issues on the LS series engines where people have had injectors replaced and this fault occuring after the repair, problem being the one or two or three..... old part number injector(s) being changed out for the new part number, when the proper repair method for changing to the new part number injectors is to change out all of the injectors to the new part number and then reflash the PCM, as the new part number injectors are a different design (high impedance vs low impedance from memory). Edit: Also, from memory, the mismatching of injectors to PCM program can cause fuel pressure issues due to the difference in flow rate of the injectors. 2nd Edit: From memory, the old Bosch part number ends in 049 and the new in 051....
Speaking of this fault I mentioned, I had an Holden Commodore 6.2 in today that had an injector replacement done for a failed injector done by a Holden dealer under warranty, the vehicle presented with rich at idle on one bank and misfire, found that the dealer had fitted one new injector and the injector that they replaced was the new part number and the rest of the injectors were old part number, have a guess which injector was still misfiring?
Had a Rich Misfire on a 2021 Silverado yesterday with no noise and only happened intermittently. After removing the valve cover with compression gauge attached for the 4th time that day....it wasn't moving! would you believe the intake lifter came apart lol?
Did you do a bleed down test before you check the injector balance? If one of the injectors is leaking like injector 8. it's going to throw off your test for injector 1 because of pressure is going to go down a lot.
so in a car that has no service port to connect the gage to measure the fuel injectors pressure, can you do that test? where would you connect the gage in that case? I beleive the fuel lines comes stright from the pump into the fuel rail with the injectors...
