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Discussion Starter #1
So, here is the story:

I had been experiencing misfires in my New Beetle (AWV engine) on cylinder 1,2&4. I changed the coil packs, spark plugs (NGK BKR6E). Found out that cylinder 4 spark plug had oil in it, so I changed the valve cover gasket. Now I have misfires on cylinder 1&2. Changed spark plugs again. Sometimes Check engine light blinks, I cleaned the TB, re-aligned it with vag-com. I checked the wires for cylinder 1&2 coilpack connector, there were some cracks on them that I fixed with electrical tape. But the misfires persist, I have codes p0301&0302. What else could I try? I am getting sick of this. I cannot use the car because of this.

Thank you for your help
 

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Ngk

I know it's a long shot but have you try a different plug? The last time I used the NGK plugs I started getting misfires during morning cold starts and I knew that was the only thing i had changed previous having that problem so I went back to Autolite Platinums and gap them at .032, Never had misfires anymore and she purrrs like a kitten. .. LOL :D hope you find the problem and welcome to new beetle.org. Don't forget to use the little washer that comes with the plug, it's there for a reason.
 

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Wife's 01 1.8T mechanic
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All you have to do is start swapping around coil packs and spark plugs. When the problem follows the cylinder, you have found the bad part. Of course, move one item at a time! The "cracked wires repaired with electrical tape" concern me, however.
 

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When do the misfire occur? Cold start, idle, under heavy load/acceleration?

Do you always get a CEL?

Do you have the ability to read real time fuel trims?

Sometimes cold start roughness will trigger misfire codes, or at least pending misfire codes, so you really have to keep a close eye on pending codes as well.

Cold start and idle misfires are typically lean conditions.

Hard acceleration misfires can be lean condition but usually points out problems in secondary ignition parts as the combustion pressures rapidly rise.

Have your coils been replaced? Some of the 1.8t coils were recalled and replaced via the dealer as well at no charge.
 

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Discussion Starter #5
Thank you for your help.

I have already swapped coil pack from cylinder 4 (which is not misfiring) to cylinder 1 and cylinder 3 to cylinder 2. It always threw the code for cylinder 1 misfire (p0301) and cylinder 2 (p0302). "Normally" the check engine would stay on and when I scan it it will show that it was a misfire. After cleaning the TB and Intake Manifold it started blinking during idle. The spark plugs were changed today. I have used the misfire counter that vag-com has and there are times that it shows up to 80-100 misfired during idle in each cylinder. Also, there is a strong smell of gas during idle. I was actually thinking to change the entire harness with connectors the coil pack that ECS Tuning has.
 

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Before you go hog wild and spend money on parts you don't need do me a favor and pull the
Plugs and gap them to .032. If you bought them from an Autoparts store then the gap is probably
Way too large. .046 is very common. Always check the gap.
 

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I don't care.....
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The other thing is when did you last change your fuel filter?

It's one of those things most people look over but can really throw stuff out.
 

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I'm not a dude.
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The other thing is when did you last change your fuel filter?

It's one of those things most people look over but can really throw stuff out.
If it's misfiring under load it could definitely be this. My car misfired like crazy on random cylinders under heavy acceleration and after replacing all coil packs, plugs, and finally the wiring harness (CRAZY EXPENSIVE) I checked my fuel trims and found I was running lean under load but was fine at idle. Turned out to be my fuel pump on its way out the door. it couldn't keep up with demand. The problem was fixed completely with a salvage fuel pump.
 

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I don't care.....
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If it's misfiring under load it could definitely be this. My car misfired like crazy on random cylinders under heavy acceleration and after replacing all coil packs, plugs, and finally the wiring harness (CRAZY EXPENSIVE) I checked my fuel trims and found I was running lean under load but was fine at idle. Turned out to be my fuel pump on its way out the door. it couldn't keep up with demand. The problem was fixed completely with a salvage fuel pump.
Exactly.

When you break an engine down its basically a big mixing pump. It needs the right amount of petrol, air and spark to make it all go bang. If anyone of those is deficient then it won't work right, simple.

So if your air filter is good, you checked you're getting spark everywhere then it can only be the fuel delivery. And vice versa for any of the others.

Doesn't matter what engine you have, they all work the same.
 

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Vacuum leaks could also be a cause of misfires.
Did you check the gap on the plugs yet?
The reason I am mentioning this, I had someone else with the exact same issue just a couple of days ago and they took the word of Autozone that the plugs are gapped at .032 I told him
to check the plugs and low and behold. They were gapped at .046 which was not even close to where they should have been.
After he regapped them to the correct specs the car ran like a bunny on Easter :D
 

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Spark plug gap for turbo & supercharged engines is far more critical.

The increase in combustion chamber pressures increases the required Voltage to fire the spark plugs.

If the plug gap is too large it will require way more secondary ignition Voltage.
 
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