Just a note. The "Rule Of Thumb" we have used for years, was anything around OR below 90 PSI will not fire at idle. Been a Ford Dealership Technician since 1987 and that rule has always proved true. Nice channel and content BTW! Patrick
Hi Patrick. As a DIY'er I'm learning and have questions. I too have a 2009 Escape with a 2.5L that has a misfire on cylinder 1. Compression is 190 and other cylinders are 195 to 200. New FoMoCo plugs and coils. When you say at below 90psi the cylinder won't fire at idle do you mean there will be a useless compression stroke because of the leak OR the the coil won't fire a charge to the plug?? What is actually detected, and by what, to create the P0301 code? Thank you, Dale
@@dalebabbitt6185 You are thinking on the right track Dale. Yes, in anything below 90 is a "useless" compression stoke. The P0301 is set due to the processor "seeing" (detecting) a slowing in crankshaft RPM/rotation during cylinder #1's power stroke. Hope this helps. Quick reply as I am at work. Best regards, Patrick
@@FordSeniorMaster Patrick, thank you so much for your reply!!! I'm buying a leak down detector and then I'll TRY to take a look at the valves with my horrible Harbor Freight bore scope. Of course I can't find the equally horrible 45 degree mirror that attaches. Wish I had a scope to see the signals going to the number 1 coil AND injector. Maybe the injector is dirty? It is on the blind end of the fuel rail, just thinking. So many possibilities going through my mind right now. AGAIN, THANK YOU, Dale
Excellent diagnostics Mike. Looks like a similar procedure that I would typically go through. I like how you took the correct steps into the diagnostic procedure and wasted no time. I like the glove technique that's very helpful. It seems like the previous tech or whoever worked on the vehicle last didn't look into the possibility of a mechanical problem that would cause that misfire.
Hey man, thanks for watching! Yeh, I agree. Mechanical is often overlooked in favor of cheaper easier to change parts...but if it's not fixed...it's not fixed, right!? Mike Becker, Senior Instructor
@@GoTechTraining I always like to rule out the simple things first, but I keep the mechanical problems on the top of my list as always a big possibility when it comes to issues like these. I don't know why, but I usually see a burnt exhaust valve in cylinder 1 on 4 cylinder engines. I assume cylinder 1 would run very hot. Also, any ideas what would have been the cause of the problem in the first place? Could be from a lack of maintenance, etc. ? I also came across something interesting from an engines textbook I read years ago regarding these problems and I would like to share it here.
A burned valve can result when an engine with an exhaust leak has been driven for a period of time without repair. The valve typically runs at temperatures in excess of about 1300 °F. When the relatively cold air in the engine compartment is sucked in through the exhaust leak, the valve suffers thermal shock.
It still amazes me how much money people will throw at a guess before checking engine mechanical!!! Thanks for watching Petar! Mike Becker, Senior Instructor
The glove on the tail pipe is a great tip, Mike. Thank you for sharing! I also noticed that I’m not the only one with a refrigerator covered with Rock Auto magnets (my full-size fridge is about 1/3 covered and didn’t even bother saving them for the first year ordering from them). Ps- I’d love a t-shirt but sadly I don’t Facebook. That’s ok, though. Cheers, Mike!
Very informative, it’s great to see information from a real mechanic that makes it simple for everyone, as a former mechanic, your video was spot on, as well as I’m also dealing with the same issue on cylinder 2. Keep up the great videos.
Awesome stuff Mike...so good to see your back at it again. You know...if it doesn't have a pocket...it's a rag. 😄👍 Oh...and it's about time you got a shop beer fridge. 😂😂 Cheers Bro
Great video Mike! All you see nowadays are misfire videos using lap Scopes which are great but there's a lot of guys who may not have access to them nor learned how to properly use one yet. This video gives some great basic tips to diag this misfire using tools that are very affordable and available. 👍🏼
Hey Robert, thanks for watching! As much as I love using the labscope, not every job is easier/faster with it. Could have used the pressure transducer here but the leak down gauge does the same thing in this regard but faster. Mike Becker, Senior Instructor
Great diag. I found the glove waving hello to be quite amusing 😁. Unfortunately it won’t be at all amusing for the customer, because that’s going to be a big repair bill. I have found that leak down and compression testing can be quite interesting in their results, and what one can show vs another in different cases. I’ve seen one case on a 2005 Honda CR-V which had 42% leakage on one cylinder, almost solely through the exhaust valves, yet compression was very good, 160 psi. The idle was pretty rough, but it ran well otherwise, and never set a misfire code, and never increased the misfire counters in mode 6. I’ve noticed over the years that when I come across an engine with a rough idle that smooths out a few hundred RPM above, when everything else checks out, it usually ends up being leaking valves when I do a leak down test. Some will set misfire codes, some won’t.
Nice quick diagnosis Mike! Hope all's well with you and your family. Assuming it's cool in temperature where your located, it's almost 90 in Palmdale Ca right now, so you may have some warm weather coming your way. No I don't own a Ford but I have a great 2020 Toyota RAV 4. Take care.
Good informative video. I'm pretty good with most repairs, but it was nice to see a job like this tackled without the super expensive electrical tools, and using basic mechanical tools more people could access more easily to figure out what is going on. Thank you!
Ah, the inertia switch to cut off fuel is a handy idea. And there's the money shot. (I won't give it away) Great tutorial Mike. I'll head on over to the Facebook page. :)
haha I do leak down tests the same way that you do and I got so much crap in a video that I posted using this method haha. But regardless, great video as always Mike!
It is absolutely crazy how the internet now makes everyone an expert.... and apparently a critic too. Personally i love your content PJ. Even recommended it to a friend in Australia this week too. His channel is Romano's Automotive i think its the best diag content from "down under"
I guess if you had the E Scan Elite Scan Software , you could do a Relative Compression Test at the OBD 2 connector . The Auto Ditex Tester will also do that from the battery . . But most of us don't have those or even a scope . The Snap On MT 2400 Vantage will also do it with an amp clamp . And if you are dealing with a " shop " WITHOUT a leak down tester - RUN
Is there a chart or book that gives the ideal numbers you should be looking for when reading live data or doing tests on components? Great 👍info on the video....thanks!
Hey Carl, thanks for watching! My main goal was to insert a load into the circuit. Unfortunately the bulb didn't light much :( Mike Becker, Senior Instructor
@@GoTechTraining I finally determined that my 2001 dodge ram has a mechanical problem; # 7 cyl has only 150psi the others are 160 170 and 175. I feel a misfire only when I rev. it above 2000 rpm in park. never feel anything when driving. I think the rings/ pistons are worn. If I put some oil in # 7 the PSI goes up above 200.
@@GoTechTraining hi mike the Autel mp808 scanner like mine has some pids that I never see explained like the cam and crank pids and distributor sync. etc it would be helpful if a video could be done explaining how to read these pids.
Would been nice to go over some of the possibilities that can lead to valve failure, I know each auto maker might be slightly different because of the valves composite!
Since the air pressure was trying to push the piston down, were you also getting air out the throttle ?? I know there is a happy zone that you can hit when doing on car valve guide seals to keep the valves from falling into the cylinders. I'm think that's piston down between intake and compression stroke.Been a while since I did heavy line work... I don't dp facebook either, besides no pocket shirt makes it a rag...THANKS MIKE.
Hey Terry, thanks for watching! You just need both valves closed and a reliable air compressor. It's no good if the compressor fails mid replacement and you loose air pressure. There's really no perfect seal, that's why the leak down tester has a green zone on it, not exact. Mike Becker, Senior Instructor
Hey Mike. Since you were going low tech, would a simple vacuum gauge hooked up to he brake booster have a bouncing needle to show the mechanical failure? Great job as always Mike.
Hey Mike, hmm it might. I'd have to try it to know for sure. It may not though, because the valve is closing, just not sealing resulting in lower compression. Not sure if it would be enough to get a bounce though. Mike Becker, Senior Instructor
Definitely depends on the car and failure. I had a Dodge 5.7L several weeks ago with a wiped out cam and seized lifters on cylinder 5 and my vacuum was at the perfect measurement both at idle and on a snap throttle
The higher the leakage, the more the needle would bounce on the vacuum gauge. The burned valve would create an EGR type affect on that cylinder. So that cylinder won't fill as much with fresh air as the other cylinders as some of the exhaust is also filling the cylinder at the same time which would cause the needle to bounce on the gauge. The larger the leakage, the more the needle would bounce.
Last year I had this happen on my 2011 Escape, shop did head replacement. 27k miles later, misfire code on Cyl 1. I take it in to the shop that did the head replacement, they can't figure it out. I take it to a different shop, exhaust valve lass supposed to be .012mm, but Cyl. 1 is at .0015mm. BUT, it has 0% leakdown. Does that mean I dodged a burnt valve? It only runs rough during a certain period while warming up, and then it smooths out.
Compression test and leak down Cyl 1 - 152 psi / 65% leakage Cyl 2-195 psi / 40% leakage Cyl 3 -190 psi / 25% leakage Cyl 4 - 200psi / 20% leakage It has low compression on cylinder 1 with 60% leakage, smoked cylinder 1 and no smoke going through intake side or exhaust. Theirs is a small leak from cylinder 1 to cylinder 2 caused by the head gasket failure but you still have good compression on cylinder 2. This was my mechanic comments for my 2010 Ford Escape due to P301 code. Head gasket is done code is still active. He thinks it could be worn piston ring. What do you think?
Hey Lee My question is what kinda smoke test? Leak down testers test at 100 psi, most smoke machines put out 0.5 psi. That’s why we use gloves to find moving air. What the compression readings and leakage after the head gasket? I would bet you have a valve issue. ~Ryan
How would you know if it's a valve and not air running past the pistons? Sorry if that's a dum question, I'm new. Just got a 09 2.5l and it drives good at high speed, but hesitates and is gutless from low speeds. Changed sparks and have one shiny piston....
Hey John, Good question, it all depends where the air goes. Air leaking past the exhaust valve goes out the exhaust, leaking past the intake valve will come out throttle body and if leaking past piston rings. The air will come out crankcase, this can be found by removing dipstick or oil fill cap. If you have a shinny piston it can be a sign of coolant consumption from a leaking head gasket or cracked cylinder head. I hope this helps, thanks for reaching out! ~Ryan
hey mike! nice diag an injector going lean caused that or just crap valves i usually put a banana in the tail pipe if it ejects across the shop i know...
Hey Scuba, no I don't think the injectors are causing the valve to burn. I don't recall fuel trim/misfire issues prior on any of the many 2.5Ls i've now fixed for this issue. I don't really know the root cause but it's likely in the design or material of the valve/cylinder. Mike Becker, Senior Instructor
Had this with my 2.0 focus and switched coils had change out plugs so did't think it was that. Make a long story short the plug center electrode was loose and moving up and down.
you should have explained you checked #3 or could have done #4 was to avoid the possibility of head gasket failure between adjacent cylinders by checking #2 for those who might not understand. i cant help but wonder the true cause maybe an exhaust restriction??? too many hot shutdowns???
Ahhh yes, you're right. I should have mentioned that!!! As far as what causes this, not really sure. Maybe just crappy OEM valves? It's soooo common on 2.5L's with 150k+ Mike Becker, Senior Instructor
Hey Paul, yeh I would think so depending on the resistance/wattage rating of the bulb. I won't be using that bulb again for that test lol! Mike Becker, Senior Instructor
Hey, sure, some videos I do show it. I'm using the Autel Elite and the Snap-On Verus Edge. I also use a Launch Torque once in a while. Mike Becker, Senior Instructor
Hey Paul, Good question, if the valve is bad enough you definitely can. You just need a borescope that can flex or has a mirror to look up toward the valve. Depending on the motor you can also spin the engine over till the valve is fully open and sometimes get a got look at it. Ryan Wilsing, Technical Instructor
Hey T.K, hard to say on the root cause on this particular engine. Head design, valve composition, could be a lot of things. Sorry, I don't really know. Mike Becker, Senior Instructor
Thanks for the reply Mike. I just repaired a 2012 Volvo T5 S60 Turnbo with a 2.5L engine burnt exhaust valve. Thought maybe u would have advice so that i could prevent it from happen again
Hey Luis, I show the valve lash specs as (Intake valves 0.20 - 0.24 mm) and (Exhaust valves 0.28 - 0.32 mm) Remember to set lash specs when the engine is cold. Ryan W, Technical Instructor
Hey Johnny, thanks for watching! You aren't alone. We'll be doing giveaways in other manners in the future, not just on FB. Mike Becker, Senior Instructor
@@GoTechTraining Hi Mike! Thank you for your reply. I don't think that the giveaways apply to me, because I'm in Europe, but I still hate Facebook and all big social media, for the privacy issues they cause and for their behavior.
Hey Johnny, I hear ya man. I understand. I would ship it over to Europe though. Make sure to join in on the ones in the future that go via RU-vid. Mike Becker, Senior Instructor
@@GoTechTraining That's nice! Thanks for letting me know! And keep up the great teaching. I'm not a car tech myself, but a software guy with a love for cars and motorcycles and a DIYer. So learning a lot from your channel and a few others.
Freaking ford junk , 72,000 miles and I have an engine misfire after changing spart plugs with fordmotor craft plugs im willing to bet this is the cause of the misfirecode for #2 cylinder ! Freaking ford junk !
