Misfire from a sticking fuel injector (no fuel misfire)

Рет қаралды 195,230

12 жыл бұрын

A common problem on these second generation GM fuel injectors. (Multec 2) They would mechanically stick closed and cause an intermittent misfire. I cannot tell you how many of these I have run across, where the customer already replaced all of the ignition components in an attempt to fix the misfire. There are multiple ways to identify a no fuel misfire. In this video we will cover a few of them. In the related videos posted lower on the page, I will cover more.
Symptoms
- intermittent misfire
- check engine light (P0300)
Fix
- clean or replace sticking fuel injector
Tests shown
- injector sound test
- secondary ignition waveform of a no fuel misfire
- injector voltage waveform showing a missing pintle hump
- misfire counters on a scan tool
Tools used
- Scan tool
- Lab scope
- Secondary capacitive pick-up
- Back-probing pin
Related videos
- How to test a fuel injector (open winding case study) Nissan
• How to test a fuel inj...
- How to identify injector flow problems (Toyota 1.8L) part 1
• How to identify inject...
- How to identify injector flow problems (Toyota 1.8L) part 2
• How to identify inject...
- Secondary Ignition Waveforms (common faults)
• Secondary Ignition Wav...
- Identifying type of misfire using tailpipe emissions
• Misfire troubleshootin...
Playlist
- (Chapters 17, 18 and 19) Fuel Injector Testing
• (Chapters 17, 18 and 1...
For more information on this topic, I have written a “field manual” called Engine Performance Diagnostics which is available at www.scannerdanner.com as an eBook or paper book.
Want even more diagnostic training? Whether you are a DIY trying to fix your own car, someone looking to become an auto technician, or a current auto technician that wants to get more into diagnostics, subscribe to ScannerDanner Premium www.scannerdanner.com/join-sc... There is a 14 day free trial.
On ScannerDanner Premium I will bring you right into my classroom at Rosedale Technical College. You will find page for page lectures taken right from my book as well as exclusive classroom type case studies. What is so special about these classroom case studies? I pull live problem vehicles directly into my classroom and we troubleshoot them in real time, using and applying the theory and testing procedures we learn during the classroom lectures. There is no better on-line training of how to troubleshoot automotive electrical and electronics systems anywhere!
Disclaimer:
Due to factors beyond the control of ScannerDanner LLC, it cannot guarantee against unauthorized modifications of this information, or improper use of this information. ScannerDanner LLC assumes no liability for property damage or injury incurred as a result of any of the information contained in this video. ScannerDanner LLC recommends safe practices when working with power tools, automotive lifts, lifting tools, jack stands, electrical equipment, blunt instruments, chemicals, lubricants, or any other tools or equipment seen or implied in this video. Due to factors beyond the control of ScannerDanner LLC, no information contained in this video shall create any express or implied warranty or guarantee of any particular result. Any injury, damage or loss that may result from improper use of these tools, equipment, or the information contained in this video is the sole responsibility of the user and not ScannerDanner LLC.

Пікірлер: 239

@mike-yp1uk 5 жыл бұрын

Hi paul, just want to give you a big thanks. Since joining your channel things have changed in my career. I used to be a frustrated parts changer. Diagnostics were to much for me. After buying your book and doing all your free videos i joined your premium channel for two years drilling this stuff into my head as i do to this day. I want to thank you now i am opening my own father and son garage. A&M auto service and sales. You opened my eyes to the world of diagnostics. Everyday i must study or i lose my edge but you explain in great detail and thats what made it stick. Thanks again for all your efforts. You are a great instructor.

@ScannerDanner 5 жыл бұрын

This is so awesome to hear. Makes everything I do have real value to me. Thank you so much Mike!

@felixarmendariz7964 4 жыл бұрын

Scanner danner is an Einstein at his work.... the smallest detail to be great. Makes work more effective.more productive. It equals to more profit.

@lanceair151 6 жыл бұрын

I can certainly vouch for the Chevron Techron in terms of unclogging fuel injectors. I recently repaired a 98 Toyota Avalon that had sat for ten years. The fuel tank and pump assembly was completely rusted, but old fuel was still in the lines up through the injector rails keeping moisture out and the rest of the system from corroding. After replacing the tank, fuel pump, filter, blowing the lines, and adding fresh gas, the engine would not start. Adding a bit of fuel in the intake proved the engine would fire right up, so I definitely had gummed up injectors. I added a bottle of Techron to about 4 gallons of good fuel and cycled the key a few times to push the mix into the fuel rail, then cracked the line open to drain the rail and repeated that draining/filling process two more times to push fresh mix into the rail and injectors. I let it sit for 30 minutes and started the vehicle. It went from no start to running on 3 or 4 cylinders. I snapped the throttle a few times, shut it down to sit overnight and when I fired it up the next morning the car ran like a sewing machine. Never had another minute trouble from it.

@jaimecarbone6580 10 жыл бұрын

This a dynamite video, the instructor gets an A, his analysis of the problem it's so easily explained by him, Thank youI just learned a lot in a just 12 miunutes video.

@mamoudbah6558 2 жыл бұрын

Man you are too good You know what, you are the best teacher i have ever seen

@ScannerDanner 2 жыл бұрын

Oh man, thank you so much. Glad your here

@mamoudbah6558 2 жыл бұрын

Thanks a lot man

@mamoudbah6558 2 жыл бұрын

I will like to get in touch with you

@keithsrepairinc1608 7 жыл бұрын

This injector test worked perfectly. Found P0307 code on a 2001 Silverado 5.3L set because of #7 injector stuck--no pintle hump. Your test videos help us all to learn more. Making better mechanics every day!

@muskman55 Жыл бұрын

Such an incredibly thorough video relevant to any fuel injection system

@danielcotayo4357 5 жыл бұрын

I like the scientific approach to solve car's problems using such advanced equipment as you do on your videos. It is a more accurate way to find what is the cause of a malfunction in the system. I really like your videos.

@PicassoPete 4 жыл бұрын

Brilliant video. Nice to see the injector waveform normalise after the mechanical tap with the screwdriver.

@jonteague7495 8 жыл бұрын

great video, we need more Tech's that will take the time to learn these things about scan tool operation. great job sir!!

@RandallFlaggNY 11 жыл бұрын

One of the best videos I've ever seen on YT.

@MaicSalazarDiagnostics 10 жыл бұрын

This video guide me in order to fix a Ford E-250 with the same symptom! You are awesome! Thanks again for all your help! Injector 5 misfire! Did all the procedure as you show here! I even got it unstuck! Replace the bad injector, now Van is running like a charm!

@ASEDoc 10 жыл бұрын

Excellent video. I'm an ASE Master Tech L1 diagnostic specialist and watching these videos is like a refresher course. The fact that you're using the Snap On scanner/scope is cool since I have the new Modis Ultra which is similar to your Verus(though I see the Verus may a little faster and more user friendly). Good work man!

@svenvos3971 3 жыл бұрын

Real nice explanation of this diagnostic procedure.

@mrbibstoo 7 жыл бұрын

Excellent presentation! Very concise and right on track. Thank you for presenting this in such detail. Might I also add that in many cases I have also been able to find a stuck pintle by using a stethoscope and listening for the audible "click" when the pintle closes. Much faster to find than hooking up a scope, just not quite as accurate.

@harold6863 5 жыл бұрын

You explain everything so clearly. Thanks so much.

@Crzyfrlss1 2 жыл бұрын

Thanks for posting this. I need to do this test later today and needed a refresher tip, was trained many years ago for lab scope diag. but was never able to put what I learned to use until a recent purchase of a Triton D8

@marceloromero9012 6 жыл бұрын

Thanks for the video, clear explanation and procedure!

@SuperGusi1 7 жыл бұрын

your the best teacher by far keep up the good work.

@ScannerDanner 7 жыл бұрын

Thanks man!

@Enrique_Osorio 9 жыл бұрын

Thank you for this video and teaching me more about fuel injector waveforms. I gladly edited my most popular video on fuel injector waveforms due to what I learned today.

@ScannerDanner 11 жыл бұрын

great compliment, thank you so much!

@michaelr6205 6 жыл бұрын

Great stuff as always from Paul!

@ScannerDanner 12 жыл бұрын

Will do, stay tuned and thanks

@ausmartin1 3 жыл бұрын

Excellent informative video on the Ecotech, here in Australia most are fitted with Bosch Injectors and way less problems, but like anything with age etc. anything will fail.

@ScannerDanner 12 жыл бұрын

@juanstrongman If you like these videos you would also like my book. Check out my website listed on my Channel page or search Auto Computers Troubleshooting (I cannot post a link here for some reason)

@Willyconrad 3 жыл бұрын

Excelent video and explanation. That’s the way to teaching

@alkhashtee 11 жыл бұрын

It is really nice tools and great job. Thank you so much for these details

@Joe_1971 3 жыл бұрын

Great video Paul...i learned something valuable.!!!

@chriscarshunting 10 жыл бұрын

Very nice. Great knowledge. Thanks for taking the time to share...

@batinhbngo 12 жыл бұрын

thank you for sharing your knowledge. Good explanation. Please share more.

@richardballinger517 5 жыл бұрын

Brilliant video, good explanation of what your seeing on the scope, could have done with this video last week. My motorcycle didn't seem to be firing on #3 cylinder. I used my portable scope (electronics engineer) to test this that and the other on a fuel injected bike for the first time.

@ziadabdelmuti9547 2 жыл бұрын

Great video thanks for the useful information

@allpromechanic1218 11 жыл бұрын

the best videos on YT

@jasaircraft 7 жыл бұрын

awesome vid and tools!

@amorozzo70 10 жыл бұрын

wow,you are the man.great video

@ScannerDanner 11 жыл бұрын

SIA 2000 and it is made by snap-on for the Vantage Pro and Verus. There are other adapters that are less expensive that you can view single cylinder events, but this thing is awesome for parade type waveforms of all the cylinders.

@cheese7837 Жыл бұрын

excellent video

@ScannerDanner 12 жыл бұрын

Yes, that is also an acceptable method, however noises transfer and you can hear injector clicking from the injector next to the one in test, especially with the sensitivity a stethoscope provides. This is why I will use a long screwdriver for the sound test as it is more muffled.

@ScannerDanner 11 жыл бұрын

im ok with that. thanks for asking Merry Christmas

@robertfloresjr8837 4 жыл бұрын

Great job!

@cfauvel 8 жыл бұрын

OMG that was awesome....I want to go back to school !!!

@trublue2319 4 жыл бұрын

Nice and fast good for us techs who use the snap on knowledge is power

@danielraymadden 6 жыл бұрын

Dan good video to the point.

@train4905 2 жыл бұрын

Superb sir.superb

@juanstrongman 12 жыл бұрын

another great vid! you should put these on a DVD I would buy it!

@tinohernandez7370 Жыл бұрын

nice job bro

@Jursaw 8 ай бұрын

Freaking intelligent guy! Learned a lot from your videos!

@jeremycaraballo3494 10 жыл бұрын

Great video

@rrmech11 5 жыл бұрын

Nice job

@ViewThis. 7 жыл бұрын

Wow! This was more interesting than a million dollar block buster movie.

@JS-ri2rx 2 жыл бұрын

Excellent thank you

@jeremycopsey5992 10 жыл бұрын

you sir are awesome

@hamiddaily 5 жыл бұрын

Really nice

@tiztiz5839 Ай бұрын

12 years later from your video Paul, i just had this happened this to me exactly chevy 3.1 all i had was. p0300 but what it was cilinder 3 injector stuck closed after days of unexperieced diagnosis i remembered your video , i smacked the injector fixed in two seconds , i am gonna try injector cleaners will see if it stays running

@ScannerDanner Ай бұрын

BG 44K Fuel system cleaner was the fix for this one from what I remember? Thanks!

@tiztiz5839 Ай бұрын

@@ScannerDanner will try , stay strong paul.

@ScannerDanner 11 жыл бұрын

@MrToolean sure. it uses a high resolution crank sensor. one that has enough signals on it to allow the pcm to monitor acceleration rates of the crankshaft between cylinder firing events. a frequency increase =the cylinder fired. a frequency decrease = misfire

@train4905 2 жыл бұрын

Superb sir.thanku.

@justynbumpus1070 9 жыл бұрын

thanks for this video! awesome!!!!

@felixarmendariz7964 4 жыл бұрын

Smart man bro.💯

@liviudaniel5082 5 жыл бұрын

great video i like it ,nice explication!help a lot !

@miltonscornertobylove5068 8 жыл бұрын

Aweson video. Every shop needs a verus lol

@ScannerDanner 12 жыл бұрын

@500hpsi Yes, you would have. I attempted to show that too but I was getting too much interference with my amp probe at the time.

@CHewYue 10 жыл бұрын

pretty interesting to see that the scanner stores previous data of previous misfires per cylinder

@ScannerDanner 12 жыл бұрын

@CoolasIce2 I have never seen a stuck open injector other than when the control wire is shorted to ground, causing a constant magnetic field. I think the fuel pressure behind the injector pintle would force it to close, maybe that's why.

@narutouzumaki6534 7 жыл бұрын

very useful G

@DavidGutierrez-zi4dy 5 ай бұрын

THANKS!

@oscarrojas4281 3 жыл бұрын

You the man

@masksareforwhitepeopleonly4311 10 жыл бұрын

thank you

@mohammedshamy6768 8 жыл бұрын

thanks Master

@ScannerDanner 11 жыл бұрын

Stuck open would result in the same pattern (no pintle hump). However the symptoms would be drastically different. Check out my video on "Stuck open fuel injector". This one wasn't stuck open mechanically but was electrically shorted to ground so the waveform would be completely different, but check out how it ran!

@vincebauer4777 7 жыл бұрын

nice video

@ScannerDanner 12 жыл бұрын

@JohnxWaynexGacy If you mean what they should look like, the answer is yes. Did you watch my injector driver designs video? It is a classroom lecture on injector waveforms directly out of my book. This video is just some of the injector material that is there. I have a complete section on injector testing too.

@Darkshadow7081 10 жыл бұрын

very interesting

@MrNerdyOne 10 жыл бұрын

good stuff

@partyboyvinny 10 жыл бұрын

very cool

@tomywoo4671 10 жыл бұрын

It's cool to see how a stuck injector would show up on a scope

@ScannerDannerPremium 10 жыл бұрын

No, as long as the winding and power and ground are good. Pintle hump location on the ramp is also variable and differs with each injector. IT is something that you would compare to other injectors on the same car only.

@MrBronze90 5 жыл бұрын

God bless you

@ScannerDanner 12 жыл бұрын

What was done as part of the "tune up"?

@ScannerDanner 11 жыл бұрын

any scope you can do this with

@MrToolean 11 жыл бұрын

Just recently found this channel, and I LOVE it! Dumb question, when you say that misfire's are calculated off of crankshaft speed, how does that work? Can you explain a little more about how the ECU calculates that? Thanks!

@arctican7483 2 жыл бұрын

GOLD!

@scientist100 3 жыл бұрын

Thank you for the redirect. It helps to see these waveforms. What would it look if the injector was clogged or if the fuel pump pressure is not enough to open the injector? I need to go back to basics from your book for sure and get to see the waveforms as I get more hands on on bad signals that I'm not 100% certain if they have a certain characteristic.

@ScannerDanner 3 жыл бұрын

A lean misfire on a secondary waveform will look like this stuck closed fuel injector. Whether that lean condition is from a vacuum leak on one cylinder, a restricted injector, or low fuel pressure. Obviously a low fuel psi condition would result in ALL of the cylinders looking like this. Check out chapter 1 for some examples of secondary ignition misfires. I have some lean condition examples in there as well. Thank you!

@mustafaqays8 8 жыл бұрын

Thanks for this helpful video. How can the ECM detect the misfile ? Is it mentioned in the book ?

@thesetruths1404 Жыл бұрын

Hi I have a 2007 Liberty 3.7L V6, 117,000 miles. Owned it since 67,000 miles. It operated perfectly for the first 30,000 miles and then it started getting a #1 Cyl misfire code P0301. It also seldomly gets a #1 cyl fuel injector circuit open P0201. It must be a very mild fault as the misfire freeze frame data shows it always happens at less than 350 rpm and when cleared it comes back immediately at next startup, cold or hot. So it seems to only happen once on startup as its moving up to regular idle speed. The miss isnt noticeable when driving or idling. Its getting 15.5 mpg fuel mileage. Doesnt burn oil. Doesnt smoke. Has great power. I've changed plugs and coils but no difference. Cleaned air intake, air filter, and ran cleaner through system. I've cleaned and inspected the injector plug and all wires but no difference. Dry / wet compression test of #1, 3 and 5 cylinders all read good: 160 / 175 psi. I'm wondering if there's a mild wire defect for that injector, or just a flakey connection somewhere. Has anyone tried to use a new set of compatible gauge wires and run them to a place closer to the injector control? I can't see where the wires go though. I'm not sure if I should just live with this, or troubleshoot it more. I don’t care about the engine light as we don't have emission requirements. Now that I know the compression is good, I'm not so worried about it. Any suggestions of what to do next? Thanks!

@sterline80 10 жыл бұрын

Scoped a 11 caravan known good today for fun, no "pintle hump" on this one. not sure if it was because it was a dif design or just so new but wasnt there

@ScannerDanner 11 жыл бұрын

You re-uploaded my videos, which is basically stealing money out of my pocket! I gave you permission to link my video NOT recopy them and make them your own with completely different web links. I have taken action against you for this.

@ScannerDanner 12 жыл бұрын

as long as you stay under 220 your fine. nothing wrong with the temperatures you have

@ScannerDanner 12 жыл бұрын

For sure, but this wasn't hard. Just a different approach. I feel the more methods of testing you know how to do for one particular problem the better prepared you will be. In my fuel injector testing section of my book. I list and describe 7 different types of fuel injector tests.

@robertmccully2792 9 жыл бұрын

Great video. If you have feed back for all injectors capability and the tool to read them. Wish i had a newer vehical and the latest snapon tool.

4 жыл бұрын

Great

@irvingcarbajal1433 Жыл бұрын

What does this injector problem do to fuel trims? Btw, thanks for your videos, they are awesome 👌

@user-ku5dr3vy4w 6 жыл бұрын

could you do a cylinder balance test,also drop each each cilinder injecter one at a time,watch scan

@Theview24 5 жыл бұрын

Paul, do you recommend any exhaust tail pipe analyzers?

@JisINSANE3 3 жыл бұрын

Well, I have a 09 ford flex I started noticing a random misfire until I started on the gas for the past few weeks. Then it clears up. today no. Constant misfire. Replaced the plugs and coil no go. The injector is not clicking. I tried smacking it a few times with my wrench. Nothing. The engine felt like it was misfiring on more then just the cylinder #5 the OBD was showing on the way home but it did not throw any other codes. Well, I just ordered all 6 injectors and doing it this weekend. I'm hoping its just that and not the damn fuel pump. I would not think so since its isolated to this one cylinder and using a sound tube there is no clicks from this injector. I'm thinking the extra vibration was the injector was getting stuck open shortly and it was hydro locking then going back closed. Strong fuel smell then no fuel smell.

@vg23air 5 ай бұрын

the techron is the ONLY product that will free sticky intake valves, I wouldn't doubt it is best for sticky injectors too.

@dreamer2355 12 жыл бұрын

Another question. Without using a lab scope, could you also attempt a fuel injector leak down test using a fuel pressure gauge and a manual device to activate the injector such as supplying 12v to the injector after disconnecting the injector wiring connector ?

@edgarcastaneda9086 11 жыл бұрын

Sr. Danner could we expect the same hump if the injector was stuck open? thanks for sharing your knowledge with all the youtube community, greetings from the border

@masksareforwhitepeopleonly4311 10 жыл бұрын

Hey Dan, good video do solenoids lose their magnetic strength over time causing slow pintle response, and can this be seen as pintle hump placement on the ramp i think i heard this in one of your videos thanks DT

@holbanology 5 жыл бұрын

Hi Paul, first off all thank you very much for you amazing lessons. Have a quick question. Its there possibity to read secundary field from ignition coil pack type?

@12mak 3 жыл бұрын

with a HT extension lead and a clamp pickup or a paddle type COP pickup

@prospexican 2 жыл бұрын

great video, i knew the snap trick, wave form, question, whats the yr make and model on this vehicle u testing? if u remember, algo is that a 3.8? w EGR?, ups never mind about my question, i saw the EGR, that one creates too much heat to number 5 injector, that's the main reason of #5 injectors going bad.

@brianwinter1453 5 жыл бұрын

Look at fuel trim also would be high because computer will compensate for lack of fuel. O2 will be a little lean on that bank 1 also no hump on from pintle is a clogged injector..