James, Weird one hey! My theory is that you had a injector with a coil that was partially open ( half the coil not being used ) and with the PCM's pulsing signal it was limiting the amount current flow and it was not creating a strong enough magnetic field to open the injector fast enough or wide enough. Although the PCM signal was doing most of the heavy lifting, when you provided a non pulsing ground, thru the test light, that extra steady 200 or so ma of current flow thru the coil, provided enough current flow to increase the magnetic field and lift it fast enough and wide enough. Just a guess, what do you think? Aside from your camera skills (LOL), your Automotive Diagnostic skills are top notch!
Nice find James, that got me thinking on how I could use a test lamps resistance to induce faults in circuits and then see how the waveform looks with the lamp's resistance. Not only do you do a nice job James, you get people to think and have ideas on how to apply things just like your brother. Good job.
Great video James Its nice to see a different approach to fault finding, as we all know in the repair business, there are many way of faulting a faulty component
Hi James, thanks for your video, it might help with a 1mz I'm about to look at. and a gift for you.... the dip in the current waveform is the injector mechanically opening and the bump in the voltage waveform is the injector mechanically closing. there is a lot of good info at pico scope auto waveform libery. Thanks -Simon, Automotive research engineer :)
This one is interesting. Good work narrowing it down so quickly to the injector. My guess would be a mechanical sticking in the pintle, causing restricted flow. When you add your test light, it keeps the injector open longer and makes the misfire better because of the extra fuel. Good video.
Great that uou put it fown to the injector. I replaced all six on my 98 rx300 as one was faulty. Once you get high mileage in these engines you really want to be proactive with maintenance and start replacing sensors and belts in ine hit if possible. My experience with older classic cars is that once components start to age fail the rest starts to go.
With the test light on the control wire grounded to battery negative it was holding open the injector and it was overcoming the mechanical force that was preventing it delivering fuel.
James Danner Yeah it is for sure. I did have a play with it on a Ford a while back it made it run real rich to the point of misfiring, but never really tried it in a Toyota. I'm going to have a play with it on a few different vehicle makes and see what it will do. If it does work well it maybe worth thinking of doing if we want to drive the fuel mixture rich to look at a response from a O2 sensor when there is no propane at hand. Providing the injector plug is easily accessible. Just a thought.
I never even thought of that. I should have done a good one for comparison. Like i said i was zipping along just looking for the control wire so i could do a flow test next when it happened. Let me know if anything comes out of your research. I did see the 'on time' pulse narrow a ms or so with test light in circuit. Good chance that could have have been the whole bank doing that
Test light/functioning injector phenomenon; a shorted injector pintle wont energized/open as much as designed due to loss of current to heat in its coil winding but when the test light is hooked up to its circuit in parallel it become an easier path to the current/voltage thus stabilizing the the shorted coil and allowing it to partially functioning during idle/low demand but this wont work on a heavier demand duty cycle as it wont allow much fuel to pass through. Good video Danner keep it up
Regarding your use of the Snap On "low amp probe" and current ramping the KG injector, the dip is known as the "seagull effect" (aka the "pintle hump"). This shows when the injector is starting to open. Typical diagnosis detecting a bad injector, as you know, is when there is initially any vertical climbing prior to the diagonal ramp. The waveform of the bad injector, with the exaggerated "seagull effect," seems to be an additional means of detecting when an injector is starting to go bad.
The misfire goes away because you input -negative feed on the negative pulse side of the fuel injector forcing the injector to open the fuel stream to the cyliinder, that is kind of dangeorius thou because if it remains like that during idle for a long period of time it may cause a cylinder hidrolock. Excelent vid James! Thanks.
So a good test might be just to ground the control circuit of the injector and see if the misfire goes away. A good test If ya know what your doin and ya can get to the injectors. PS like your no nonsense approach you seem to make it fast and easy. You have a lot of good tips.
thanks for the compliment. i do waste a little time on the video filming part and do a few things i probably wouldnt do normally just to get more content. but i like doing it and learn in the process. thanks again for watching
Good video . I could see where you were working on the engine . I could see the data and graph on your scanner screen . I could hear your narration even over the engine noise but despite the excellent filming tech. my eyes were rolling back in my head.. . If you and thousands of other RU-vid instructors could tell the viewer , an inexperience viewer in my case. the conclusion .. That is what was the cause that you found for the misfire early in the video. before you get to the reasoning , the experimentation. they trial and error exploring .. /By me knowing that you found the problem and what was the problem I can keep focused on the video even when you are talking about things I don't understand.
I can understand and appreciate not wanting to waste time on a video, only to find out it's inconclusive. unfortunately I am filming while I work. I don't stage a problem I already figured out. u r just watching live in essence. I will keep that in mind in the future. thank you for participating
I have 00 es300 same engine same issues. I’ve changed out ignition coils and all injectors and Vt solenoid on both sides of engine. Still getting same outcome but I know my cat on rear needs replaced. Gonna do that today possibly,,,,, get back to u.
Hey James, GREAT VID, But I just wanted to give you my input & kinda similar Sit., W/ a 1997, Altima, kept having a, Mis - Firing Code, on Cyl. #1, no Matter what I Tried, #1, #1, Long story short, took out the - - INJ. - For #1, The INJ. Was fine, Ohms. Were right on Specs., BUT What I did Find, was an INJ. "O-RING", The inner rubber of the - O--Ring, was split--broken perfectly & was Covering the - - 2-holes of the INJ. IE. CAUSING-- Restriction, there - for, Causing the - - Mis - Fire!, NO problem just went to Nissan & Replaced all, 4-- 'O-Rings' (4-cyl.) Eng. Put it back together, Erased the Code, Everything back Norm, running 🏃 like a Champ!!!
Great video! Seen patterns with shorted injectors, but can't remember seeing a partially open(theorizing)? one before. Keep up the great work,thanks for the lesson.
James Danner Was agreeing with what Billy R. was saying,I think static ohms was one thing but when amperage started flowing is when your partial open showed up as seen by the amp ramp.
I guess I'm super late, and I actually starting watching the second video first lol, oh well I haven't seen the solution yet but I'll make my guess now. It's a bad injector for sure, I'm gonna say the coil has shorted internally and adding the test light in a series parallel circuit put the resistance closer to where it needs to be to open the injector. I suspect scanner danner will get a waveform in second video, I also suspect there will be no injector open hump. Fingers crossed.
thanks....love the problem solving....can you do damage to the injectors sending thru too much current when gounding externally the injectors ?...thanks again...bob
Paul said maybe a peak and hold style that grounds fully initially then limits the current flow with a duty cycle or higher resistance to ground.which u would see on a ramp test as an initial rise then a flat top. or diesels . but mine, the pcm clearly pulled to total ground as evidenced by the 0 volt line on the waveform. so my guess is no. cause u wont be sending any more current than would be done thru the pcm. that being said, i wouldn't hold it to ground for an extended time.just pulse. you would at minimum fill that cyl with fuel...bad.
i wonder if the test light gave it a bit better ground and slight current flow increase on the faulty injector force it to perform a tiny bit better again?
I have a 2002 avalon and mine seems to want to cut out at around 41-45mph so I changed all plugs and coils except number 1 very difficult to get to for me one moment the car is running as it should for sometime and entire day even had check engine light go out completely well now it's back on and still doing it as it pleases then it begins to flash and code say random multiple misfires 135 so I change all except one any chance it just may very well be that last one I haven't changed yet ???
I have an 03 avalon and I'm getting mine looked at tomorrow. I have the same problem. I have been looking around and the EGR valve might be stuck to open.
You had some specialized equipment there. But for those of us with only the OBD II scanner tool. If the scanner points to a cylinder misfiring, can't we just put in a new spark plug into that cylinder and then swap the coil with a known good(front bank, easy to get to) coil. If the misfire on the scanner moves to the swapped location, the injector was bad. Disclaimer. It has been 35 years since I was a professional mechanic. It was carburetors at that time.
would have like to see ohm test on injector and flow test on car ... or if you have equipment flow test off car would be cool video. tell your brother take that inj and hook it up off car in flow bench with scope and show us the pintle and test light theory. that would be really cool...
I wish I had the equipment and, more importantly, the time to do that stuff . unfortunately that part is long gone. maybe the next one I see, I'll give it to him for class.
iv a 03 avencis starts perfect in morning at runs great aslong as driving but when stop for lights or roundabout check engine light comes on n it wont go I have to turn car off n then start it but takes ages tryin to start n av to av foot to floor any help greatly appreciated
So, where the hell IS Bank 1, Sensor 1 located on the 1997 Toyota Avalon. Dealer, shops are all telling me it is the one nearest the radiator, just in from cyl 6. How can that be true when everyone knows that Bank 1 is ALWAYS in Bank 1 - which in the 1997 would be at the FIREWAELL side, ya? It is a 2-wire sensor, btw.
@@jamesdanner7850 thanks for that by the way and and wallets been two years now I got the same kind of readings you have almost identical shows the problem is 1 and 2 but it's actually it's a dual coil and and the one side is faulty and two is taking the brunt of it. the mister I was definitely on one so I got to AutoZone borrowed one of their Cheshire cat switcher it's got a pressure gauge in mm in a meter off-road testing the injectors and injector one salty so I'm changing out all the injectors and all the spark plugs spark plug wires and spark plugs and why not the coils too! well you got to figure it's got 320k+ mikes on it right now.
Did you try ohm testing the bad injector and comparing it to the ohms of the new injector? Would this determine if the coil is failing or there is an issue with clogging? Injectors can be 'flushed and cleaned' fairly easily off the engine
i did ohm check the faulty one and one that worked. both had 15.1 ohms. but when key was on, power in ckt, the bad one dropped to 13, the good one didn't change. i know that's probably not a legit test but add that to theory building. i honestly don't know if a sticking injector would be visible on a graphing scope. thanks for feedback
James Danner I'm pretty sure that 2.1 ohm difference is enough evidence to say the injector was failing. Glad you checked it under load, cause that's something I was wondering. Thanks for replying and posting the video
James Danner James, your ohm test revealing a 2.1 ohm drop on the bad one, to me, is enough to confirm what I originally said about it being partially open ( Only half the coil being used ) under load, and you provided that extra boost of current ( With the Test Light ), providing a stronger magnetic field to open the injector all the way. It had to be at least, partially open, not completely open, or there would had been no current flow at all, when you put the test light to it. In my theory the injector was just barely failing, barely! Keep in mind, as I said before, the PCM was doing most of the heavy lifting and giving it the proper pulse-width, well sort of ? As far as detecting a stuck injector on a scope, I would think, maybe!, you would see a rise in amperage to a point and then it would flat-line, if it was sticking? Just Theory Building! LOL !
Billy R After rereading my previous posts, I realized I kept saying a partial open in the injector. I apologize, what I meant to say is a partial short in the coil internally to it's self not to ground, causing only half the coil to be used. But if there was a total open in the coil it still would have no current flow with or without the test light!
Billy R if it was partially shorted,wouldnt the amp ramp sharply increase instead of dipping down like it did? sorry to beat a dead horse but learning by asking.
thats where i think the consensus is. my test lights path to ground, although high in resistance. kept the field from collapsing as fast as it should, allowing the injector to stay on even a ms longer
Hey James! I have this same car and its not coming up. No start actually. I have replaced the fuel pump but it seems no power at the pump and the relays seems to work fine. I would be glad to hear any suggestions.
That would be wonderful. The car has been sitting down for some weeks and i'm running out of ideas as i am very new to the DIY lifestyle. Would be looking forward to any help or suggestions. Thanks
+Suleiman Adams so if you think we r dealing with the fuel pump. It gets power from the CIRCUIT OPENING RELAY which is behind the drivers kick panel. My wiring diagram shows terminals 1,2,3 and 5 1 should have power from the ignition switch Run and start 5 should have power from the EFI relay in the left front of engine compartment 2 is the ground control from the computer 3 is the one feeding pump So if u have a test light ,, hook it to ground and with the C.O. relay unplugged you should see power on one with key on run and on crank Another should show power too but it may be only for a few seconds on run but constant during cranking. If u hook the test light to battery positive, One ( terminal 3) should light up the test light confirming there is a ground path thru the pump The last one, no 2, may light up test light for a short time when u initially turn key on but definitely should when cranking Start there
Your videos and knowledge are awesome ! If Ya wanna hear some screw ups I have a few over the last nearly 40 years workin on cars !!!! Maybe you should have a video having guys listing there top #1 mistake ???? Remember old Chryslers that had left hand lug nut threads on the left side only ? I broke 2 off before I figured out what I was doing !!!! OMG.
+Keith Baldwin does it run on starting fluid? Like a no fuel scenario. Or not, like a no spark. I have a video on a Toyota where one of the coils shorted out and shuts the car down. U have any codes?
Unfortunately no. At least with the snap on. Some fords u need to use the cylinder contribution functional test. Some only say yes or no on a misfire pid
Stop Doubting, Just Believe. I don't understand what you are trying to say. Stop doubting ourselves, just believe we can do it? I'm seriously just confused about the message at the end or your video.
+Linnae Cotton I have a different video on a Toyota or Lexus with misfires all on the same bank that has a vvt solenoid that is sticking and causing 3 cylinders to misfire together. I need to know more,like all the codes to start
Hello, I need your urgent help, I have a toyota prado, when I use the flashing lights, does not work, but the instrument panel lights (cluster) turn on as if I use the navigation lights. sorry my english, greeting from venezuela.
and never heard of a prado. maybe not American market. but it sounds like you have a grounding problem if the turn signals are back feeding thru cluster lighting
hi bro, how are you, greetings. I disassembled the fuse box, check all wiring harness, replace the cluster, button flashing lights, we put candles and pray much, hahaha .. but the problem persists, now check this out, I turn on the lights, high and low , Remove the fuse and where supposedly should go negative current passes positive current. is this sucking positive current from somewhere but can not find the short circuit. when I turn on the flashing lights, the cluster turns like turning the ignition swicht. it is a toyota prado fzj90 5VZ 6 cyl. landcruiser in Venezuela. I have also one toyota tacoma 2007 Electronic ignition button when I turn the truck, lights brake lights but no ignition. hahahahahaha ....... greetings from Venezuela. sorry my english
It kinda acts like an intermittent Ground, I know I had a 98 Avalon that had a an intermittent misfire, it only had 3 coils. The misfire was on cylinder 5, I tried swapping coils, cleaning the injectors, everything, finally I ended up switching injectors 5&6 and the problem followed the injector, definitely a bad injector!
Sorry for the resurrection but when did your car misfire? My girl has an 08 rav4 that has an intermittent cylinder one misfire pretty much only going up hill
i was thinking that at first as well but on the voltage test it looks like the ecm is pulling down cleanly to near zero. but u are right, i am adding an additional ground path that seems to help. albeit thru a light bulb
James everybody on the internet thinks they can do it better. My guess is the test light is holding the restrictive injector open thus fixing the misfire. Good find and thanks for the video.