2001 1.8T

When it happened: I was sitting at a stop light, car ran great up to that point...then I tried to take off. The car misfired pretty badly, out of no-where. The car runs, but misfires badly under acceleration..I haven't gotten it above 30mph since the problem started.

Vag-Com Says Random Misfires, and misfire in cylinder #3 & #2. Got new coil pack, nothing solved.

Notes:

• Fuel injectors are 440cc and are only 30k miles old
• Fuel pump less than 3k miles old
• Fuel filter less than 3k miles old
• Plugs less than two (2) miles old
• Car ticks a little bit - not sure if this is pre-existing
• Car has half tank of gas - dur!
• Unplugged MAF, still misfires
• Messed around with connections profusely (original wires), misfire cont's.
• Never misfires when COLD. Only after the car warms up
• It's not the injectors, I already switched #1 and #3, cylinder #3 misfire cont's.
• Logged Misfires on blocks 14-16, misfires ONLY on 2 & 3, no matter which configurations I arranged the coil packs (#1 to #3, #4 to #2, etc)
• AWB engine
• The 2001 A4 does not have an ICM (Ignition control module)

Codes:

1. 16795 P0411 Secondary Air Injection System (B2) - Incorrect Flow (This has been a re-appearing code, I have always cleared it, and it wouldn't pop up for weeks).
2. 16684 P0300 Random Misfire Detected - Any Cylinder
3. 16687 P0303 Cylinder #3 - Misfire Detected
4. 16686 Cylinder #2 Misfire Detected - OCCASIONALLY

If anyone has had this problem, PLLLLLEASE speak up. I am so unfortunatelly low on cash right now it's disturbing...I can't have it towed

****I Update this first post as the thread goes along, all the info I know, is in this post***

 

I'm no expert with the 1.8 motor, but from what I've read on here, it sounds like you could have low compression on that cylinder. I'll wait for someone else to confirm that, but it isn't unlikely considering the problem doesn't follow the coil pack.

 

first- stop driving it immediately. driving with a misfire melts your catalyst, which you probably did already, and can destroy your O2 sensors.

after you cleared the codes and replaced the coilpack the misfire stayed in cyl 3?

i noticed on my car that when the MAF went bad, and i immediately unplugged it, the car would still run like crap because the fuel trims were so messed up already. it takes a little while to get back to normal. clear the codes to reset the fuel trims, unplug the MAF, then start the car. if it still runs like that its not the MAF.

 

I don't run a cat.

The misfire stays in cyclinder 3, and 2, no matter what arrangement I have the coil packs. I checked and cleared the codes two dozen times driving around trying to pin-point the coil-pack.

I thought I cleared the codes before I unplugged the MAF, but it is possible that I did not, thats a great suggestion.

 

Update: it's not the injectors. I'm completely out of ideas. Totally clueless. HEEEEEEEeeeeeeeeeeeeeeeeeeeeeeeeeeeelp

 

have you tried swapping wires?

 

Run a compression test. If it passes, proceed below.

Check the coil pack connector contacts. Make sure the connectors are not cracked and the contacts are not broken.

Check to make sure the coil packs are Audi genuine and dated 2008 (or newer). Older 2001 coil packs are notorious for failing, often at the same time, and often only when warm.

Check to make sure your spark plugs are correctly gapped for your set-up.

Check you ECU to make sure it's not under water and the connector is clean. Possibly pin-out the harness for continuity. Compare cold resistances to hot to determine possible worn or partially broken or corroded wires.

Call the software company.

 

replace the coil pack harness

 

i had the same kind of issue in my 99 a4 1.8t, codes for cyl#4 misfire, and really bad stuttering and hesitation. turns out a banjo bolt on the wastegate had loosened up and fallen out, so the wastegate was not opening up at all, and it would boost to the max, then cut out. put a new bolt in, changed the plugs , and she runs like a champ now...

 

you say you have only done 2 miles on new plugs have you concidered putting old set back in and seeing what the engines is responding like . i had a misfire on number 3 on my a3 t the ignition module had gone down on only one but the new bosch plugs i had put in were not suitable even know they were reconmended they ran very weak so put back in ngk r6 plugs runs atreat.