2.7T misfire hunt (I'm stumped!)

[JTapper]

I've been having a misfire for a few weeks on Cyl 5. I picked up a set of used good coils from Cole last weekend with the hopes of that solving the issue until I decide if I want to do the FSI coil conversion.

Logging misfire with vag-com in Measuring Block 016

I swapped the coil with a supposed good one - Misfires on cyl 5
I swapped the supposed good coil with another supposed good one - Misfires on cyl 5
I swapped ICM's bank 1/2 - Misfires on cyl 5
Checked spark plug, looked good, but swapped it with cyl 6 - Misfires on cyl 5
Checked injector connection, removed and replaced plug - Misfires on cyl 5
Swapped cyl 6 coil (no misfires) with cyl 5 - Misfires on cyl 5

The only other thing I can think of is a bad injector. Any other thoughts? All the wiring seems to be in good shape with no damage. I saw one misfire on cyl 4, and one on cyl 2, but the rest had none detected.

[Jigs]

I have heard of a lifter in the process of failing causing the same issue on a friends 2.7t.. He said the lobe for his cylinder 3 was way worn and the lifter was in the process of failing which caused his constant misfire no matter what he did. He replaces all the lifters and threw some different cams in and he has not had a misfire issue since... Maybe not your issue but I figured it would be some food for thought.

How many miles on your rig?

[JTapper]

I have heard of a lifter in the process of failing causing the same issue on a friends 2.7t.. He said the lobe for his cylinder 3 was way worn and the lifter was in the process of failing which caused his constant misfire no matter what he did. He replaces all the lifters and threw some different cams in and he has not had a misfire issue since... Maybe not your issue but I figured it would be some food for thought.

How many miles on your rig?

155k.

The head on that side was replaced at 141k with a used head I got from Chad at SCI. I think he said it had around 75k on it.

[Jigs]

IDK what it could be then. The single cylinder misfire no matter what the condition makes me still feel like it may be lifter or head related. If it was electrical you would think that the whole bank would be misfiring.

Just an FYI my buddies 2.7t had 120k on the clock I believe when his went to hell. I will call him up and ask him what other things he could think it would be since I remember him checking a million things before he cracked the head open and found out that the lifter was the problem.

[veedubmechanic]

you mean the 3.0 jigs... thats a common prob.
http://forums.vwvortex.com/showthrea...lifter-failure

Swap the injector Jeff. Also do a compression test.
Its not a coil problem.

[Jigs]

you mean the 3.0 jigs... thats a common prob.
http://forums.vwvortex.com/showthrea...lifter-failure

It happened on a 2002 2.7t not a 3.0L.

I second the compression test.
My buddy said to check:
- Compression
- Check the grounds
- Check/swap injector

[JTapper]

you mean the 3.0 jigs... thats a common prob.
http://forums.vwvortex.com/showthrea...lifter-failure

Swap the injector Jeff. Also do a compression test.
Its not a coil problem.

That's the plan. If compression is good, I'll be swapping the injector.

The injector is really the only high mileage part left. Everything else has been replaced. ICM's were done at 112k according to the PO's pile of records from Audi North Scottsdale.

[JTapper]

Compression is okay at 150-155 across all six. Swapping a few injectors tomorrow. If it is the injector, I'll probably soak it in gun solvent, then order up a whole new set for installation later on.

I'm going to borrow a set of ICM's as well to see if for some reason they actually are the problem.

[Stack]

I know you swapped coils several times around and I chased something similar on an S4... It eneded up being the coil boot...

Something to check

Also double check the lead going to said coil... Bad grounds cause havoc on electrical systems

[JTapper]

Replaced both ICM's and all is good in the world.

[veedubmechanic]

good deal, now do the FSI conversion so you have an increase in throttle response and boost spool up

[JTapper]

good deal, now do the FSI conversion so you have an increase in throttle response and boost spool up

Meh...I've talked with a few folks who have done that locally, and it doesn't seem that the difference was too noticeable.

I have a local source for the adapter plates for a reasonable price, and after selling the 12 good coils I have, and the three ICM's, I should be able to be into a conversion for around $100.

[veedubmechanic]

I cant vouch for the 2.7, but I know on my 1.8t it was night/day difference.

[JTapper]

I cant vouch for the 2.7, but I know on my 1.8t it was night/day difference.

Both of these were 2.7's.

One was stage 2, and the other stage 3. Obviously the story from the stage 3 guy shouldn't matter for my application, but him seeing no difference was actually surprising.

Someone just needs to do before and after dyno runs and settle it once and for all.

[veedubmechanic]

I know for the 1.8t before and after dyno runs it showed 11hp I believe with a modded ko3 chipped.