Cylinder 6 missfire - CEG Archives

UIM/LIM Rebuild in Duratec Maintenance FAQ
http://www.contour.org/ubbthreads/showflat.php?Cat=&Board=v6maint&Number=958650&page=0&view=collapsed&sb=5&o=&fpart=1

Originally posted by cannondalemtb:
Well my car was missfiring about a month or so ago and then it stopped. It was running fine until last week. The code came up as a missfire on cylinder 6. So I replaced sparks plugs and it still missfires. I then replaced the wires and had the code checked again and it is still cylinder 6. I removed the coil pack and the terminals look fine. ANY ideas?

Wow you have been busy since last night. Did you just replace the #6 wire?

If you are going to do a injector replacement, then we should take a whole Saturday and do the whole teardown/ rebuild IM cleaning!

I would sure try some injector cleaner before replacing any injectors.

Since the new plugs didn't work, I put my Ford Racing wires back on and returned the the new ones. I then started it up to drive to the gas station and it wasn't missfiring! But then halfway there, it started again. So I added injector cleaner when I filled my tank and now I am just waiting to see if it'll make a difference.

Originally posted by Big Jim:
I would sure try some injector cleaner before replacing any injectors.

Jim,

Does injector cleaner really help? What kinds are good?

Well, I just took her out again. It seems that it does not missfire when it is cool, but once it warms up, the missfire won't go away. Does that make any sense?

Originally posted by cannondalemtb:
Well, I just took her out again. It seems that it does not missfire when it is cool, but once it warms up, the missfire won't go away. Does that make any sense?

That's usually an ignition problem.

Originally posted by Ex-Mean'Tour:

Originally posted by Big Jim:
I would sure try some injector cleaner before replacing any injectors.

Jim,

Does injector cleaner really help? What kinds are good?

Yes, it usually helps. Ocassionally a very dirty injector will not respond and will need something stronger or need to be replaced.

I like RedLine SI-1, the better Techron (not Pro Gard), Valvoline Synpower Injector Cleaner, BG 44K, MOC, and Regane. Stay away from the cheap ones.

Originally posted by Big Jim:

Originally posted by Ex-Mean'Tour:

Originally posted by Big Jim:
I would sure try some injector cleaner before replacing any injectors.

Jim,

Does injector cleaner really help? What kinds are good?

Stay away from the cheap ones.

Will they hurt, or just snake oil?

Originally posted by Ex-Mean'Tour:

Originally posted by Big Jim:

Originally posted by Ex-Mean'Tour:

Originally posted by Big Jim:
I would sure try some injector cleaner before replacing any injectors.

Jim,

Does injector cleaner really help? What kinds are good?

Stay away from the cheap ones.

Will they hurt, or just snake oil?

The cheap one probably will not hurt anything, but they just won't do much. Yes, the cheap ones are just snake oil.

Well, for lack of not seeing any other products, I did put cheap stuff in it. I added STP fuel injector cleaner. At first it seemed to be working and the car was fine today. But then when I shut the car off, the engine continued running even though the tach was at 0 and then it took about 20 seconds before it actually turned off (it did this once before about a month or so ago). I then came back to the car a short time later and the car began missfiring again.

I know this might not be related but does anyone know why it would continue running? Also, should I try the Chevron Fuel Injector cleaner after this tank of gas?

Originally posted by cannondalemtb:
...I know this might not be related but does anyone know why it would continue running? Also, should I try the Chevron Fuel Injector cleaner after this tank of gas?

Yes. Sounds like "dieseling". The throttle is partially open when the engine is turned off. The hot engine has sufficient fuel to continue to run without spark from the spark plugs.

Clean the Throttle Body and you also need, at a minimum, the UIM cleaning using vacuum method. Maybe even a UIM/LIM rebuilding.

in Duratec Maintenance FAQ
http://www.contour.org/ubbthreads/showflat.php?Cat=&Board=v6maint&Number=958650&page=0&view=collapsed&sb=5&o=31&fpart=1

TB cleaning.
http://www.contour.org/ubbthreads/showflat.php?Cat=&Board=trouble&Number=920243&Forum=trouble&Words=p0401&Match=Entire%20Phrase&Searchpage=0&Limit=25&Old=allposts&Main=919728&Search=true#Post920243

Well I cleaned the throttle body today and there was a ton of build-up on the inside. The UIM and LIM will be cleaned sometime soon after seeing all this.

This side was not bad and although it looks black on the perimeter, it is not. Just my bad picture taking skills.

In these two pics you can see the heavy black (carbon?) build-up on the inside of the throttle body.

Sorry for the crappy picture quality. I cleaned it using Berryman's B12 and it came out lookin good! I forgot to get after pictures though.

As for the missfire...
When I took it out to test the throttle body, it was not missfiring. The car did feel a little more responsive, but I think it was just in my head. Plus it always feels better when it isn't missfiring. Anyways, I took it out again later and it was missfiring. Then on my way home it was still doing it but then I coasted down a large hill in neutral and then stopped at a light at the bottom. When the light turned green and I accelerated... NO MISSFIRE. It was fine for the rest of the ride home. This car has a minds of it's own.

Yo Bob,

I know how to do the vacuum suck method of cleaning if you wanna give it a quick try. Grab a can of Berryman's or Sea Foam (I prefer Sea Foam). Tonight?

Then you should schedule a Saturday and we can tear it down. You will need $60 - 75 worth of stuff; gaskets, tons of Berryman's, etc.

I think I might try to do it all this weekend. Maybe Sunday. Or the next weekend.

Originally posted by cannondalemtb:
I think I might try to do it all this weekend. Maybe Sunday. Or the next weekend.

"All" meaning what? The teardown and rebuild? I doubt Pride Fahd (f'ers) would have the gaskets, etc. that you need.

True. Maybe I'll order them this weekend and plan on doing it all next weekend...

Originally posted by cannondalemtb:
True. Maybe I'll order them this weekend and plan on doing it all next weekend...

Have you seen the step-by-step instructions? Check:

Here
and
Here
and
here (tips and tricks)

I could try and come help for a while, if you like.

Yeah, I've seen all those. I'll give ya call and let ya know when I plan on doing it.

Just ran into an old post talking about this identical problem. Runs good when cold, then skips when hot, lousy performance, etc. These guys were talking about the CRANKSHAFT POSISION SENSOR being bad, and upon replacement, the car running like a scalded dog! Here's a link to the post:

http://www.contour.org/ubbthreads/showflat.php?Cat=&Board=trouble&Number=1209527&page=2&view=collapsed&sb=5&o=7&fpart=10&vc=1

Go to page 10 in the thread and it has a good illustration as to where it is and how to get to it. I'm going to try it myself, as I have the exact same issue with my car. I guess this is common and people end up replacing all kinds of stuff with no results.

The part is $13.50 at Autozone!

http://www.autozone.com/servlet/UiBroker?UseCase=C001&UserAction=doYMME&Parameters=Auto+Store%7C%7EREGULAR+PARTS+LOOK+UP%7C%7E00111

Mike

PS--though it didn't fix my car completely, cleaning out the throttle body with carb cleaner and a toothbrush did help a lot. Only takes about 5 mins to bear the thing and just clean it on the car. Make sure you pull fuses 4 and 11 in the fusebox by the battery to clear the computer's memory or it'll continue running crappy!

Welcome mbryant107

. Thanks for posting.

I removed the throttle body and cleaned it completely. Are you saying that I should still remove fuses 4 and 11?

Removing Fuses 4 and 11 for a few minutes clears the codes and resets the PCM. If you disconnected the negative battery terminal before taking out the TB, it also cleared the codes and reset the PCM (including clearing the radio stations and clock).

Originally posted by mbryant107:
Just ran into an old post talking about this identical problem. Runs good when cold, then skips when hot, lousy performance, etc. These guys were talking about the CRANKSHAFT POSISION SENSOR being bad, and upon replacement, the car running like a scalded dog! Here's a link to the post:

http://www.contour.org/ubbthreads/showflat.php?Cat=&Board=trouble&Number=1209527&page=2&view=collapsed&sb=5&o=7&fpart=10&vc=1

Go to page 10 in the thread and it has a good illustration as to where it is and how to get to it. I'm going to try it myself, as I have the exact same issue with my car. I guess this is common and people end up replacing all kinds of stuff with no results.

The part is $13.50 at Autozone!

http://www.autozone.com/servlet/UiBroker?UseCase=C001&UserAction=doYMME&Parameters=Auto+Store%7C%7EREGULAR+PARTS+LOOK+UP%7C%7E00111

Mike

PS--though it didn't fix my car completely, cleaning out the throttle body with carb cleaner and a toothbrush did help a lot. Only takes about 5 mins to bear the thing and just clean it on the car. Make sure you pull fuses 4 and 11 in the fusebox by the battery to clear the computer's memory or it'll continue running crappy!

Nice. Bobby, that is one of the things I changed on my car before . . . I can help you. It is actually pretty easy you can probably figure it out on your own. At least check your wiring as it is pretty close to the belt.

The Camshaft sensor on the other hand... That's a bear!