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audisnapr
07-30-2013, 05:44 PM
2000 A4 1.8t (ATW)

here's the Cliffs notes

Driving to work, coilpack failure.
Limped home where I swapped all 4 plugs (it was time), semi-stripping one plug hole and replaced the bad coilpack.
Gambled by driving it again. Plug threads failed. Burned up the plug and coilpack.
Limped home on 3 cylinders. Idled rough of course, but still idled and drove.
Parked it.
Pulled the valve cover, added plug thread insert, replaced valve cover gaskets. Reassemble.

I had what I thought was an old, but good coilpack to replace the one that burned up. Started the car, but felt like it was only running on 2-3 cylinders and wouldn't keep its idle.

Bought two new coilpacks from the dealer today. Still no luck. Swapped the coilpacks around, pulled the plugs, but they are wet and smell like gas confirmed by the rough idle and tough start.

So besides the obvious that I'm a moron for stripping then driving with a stripped plug, what am I missing?

I'm getting no new codes. It won't even tell me which cylinders are misfiring.

Ugh.

Poopie
07-30-2013, 05:50 PM
Sounds like the issue started before all this. Maybe the first incident wasn't a coil pack failure. I think the fest thing you need to do is fire up the vagcom and see which cylinders are misfiring. Do a compression check too.

audisnapr
07-30-2013, 05:54 PM
Sounds like the issue started before all this. Maybe the first incident wasn't a coil pack failure. I think the fest thing you need to do is fire up the vagcom and see which cylinders are misfiring. Do a compression check too.

hmm, I guess it's possible, but when I got home and swapped the plugs and found the bad coilpack, it drove fine (and by fine I mean very nice because of the new plugs) for a good 7-9 miles before the threads on the plug failed. Believe it or not I think the cylinder that had the plug failure is one of the 2-3 that is firing just fine now.

BTW, when I said it isn't throwing any new codes, I meant that VAGCOM isn't showing me any new faults. I've been checking this whole time.

Poopie
07-30-2013, 06:13 PM
Did you unplug the maf? Do you feel like its electrical or mechanical?

Poopie
07-30-2013, 06:14 PM
I was excited to see you post though. Not excited to see you having car troubles.

audisnapr
07-31-2013, 07:09 AM
I was excited to see you post though. Not excited to see you having car troubles.

Thanks, poopie. I'm around. I check in from time to time, just don't have much to contribute these days.

I did not unplug the maf, but even if I had it would run a million times better than it is right now. Hard to say if it's elec or mech, but it cranks just fine. It'll start and struggle. I can get it to the low 2000 rpm and hold it there fine (even feels like all 4 cylinders at 2000rpm).

What am I missing here?

Sent from my SGH-T999 using Tapatalk 2

walky_talky20
07-31-2013, 07:29 AM
Maybe too much moving around of the coil pack harness has damaged the brittle wires.

Check for good hot spark on all 4 cylinders.

audisnapr
07-31-2013, 07:39 AM
Maybe too much moving around of the coil pack harness has damaged the brittle wires.

Check for good hot spark on all 4 cylinders.

thanks. Yeah I looked at the wires. I pulled the boots off all four plugs and there are a couple wires where the sheathing is cracked with bear wire exposed - nothing horrible, but...

Question, will a coilpack fire a plug if it's not bolted down and grounded to the valve cover? I thought about checking the spark, but was concerned a coilpack wouldn't fire unless it was bolted down/grounded. The coilpack casing has a little lightning bolt at one of the two bolt holes which to me means ground.

walky_talky20
07-31-2013, 08:53 AM
The coil pack doesn't even need a spark plug in it in order to fire. It just needs a ground to jump to. I test them by sticking a screwdriver in the end of the coil pack. If you pick the correct size of phillips head screwdriver, it will clip in the end nicely. Then hold it so the shaft of the screwdriver is about 1/16" away from the valve cover or other ground. Then crank the starter. You should see a nice blue spark. Doing it this way you can now dynamically increase the air gap to see how "strong" the coil is. Increase it too far and it can no longer jump to the ground - it may jump through your hand instead. So be careful.

They actually make a tool for this so you can dial in the gap with some precision to better compare across coils and such (and not have to hold it by hand):

http://www.vintagecb750.com/parts/480/35-8020.jpg