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Discussion Starter #1
CEL Code: PO171

Tried: Cleaning MAF and reseting code, still has misfire and the code comes back miles later.

When it misfires it's only at idle, no power loss when driving, no bucking, no hesitation. The car sat with the same gas for probably all summer, I've ran 2 tanks through it and a bottle of fuel injector cleaner. It doesn't always misfire when at an idle, this morning it was great. I started it, no problems drove 40 miles stopping at lights and signs no problems and then I reach my destination and it starts to misfire. I get home and I let it idle for a bit and it starts doing it and I notice a little smoke coming out from my exhaust. White. When it misfires I also smell fuel. Before I start wrenching, I want to get a couple opinions, I think it might be fuel injectors but I also think that if it were fuel injectors it wouldn't have power and it would misfire while driving.

I have brand new plugs in it, probably 2-3k old, autolights.
 

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CEL Code: PO171

Tried: Cleaning MAF and reseting code, still has misfire and the code comes back miles later.

When it misfires it's only at idle, no power loss when driving, no bucking, no hesitation. The car sat with the same gas for probably all summer, I've ran 2 tanks through it and a bottle of fuel injector cleaner. It doesn't always misfire when at an idle, this morning it was great. I started it, no problems drove 40 miles stopping at lights and signs no problems and then I reach my destination and it starts to misfire. I get home and I let it idle for a bit and it starts doing it and I notice a little smoke coming out from my exhaust. White. When it misfires I also smell fuel. Before I start wrenching, I want to get a couple opinions, I think it might be fuel injectors but I also think that if it were fuel injectors it wouldn't have power and it would misfire while driving.

I have brand new plugs in it, probably 2-3k old, autolights.
It sounds exactly what my car was doing and it was a bad coil pack. I have 4 of them and I had changed them a year ago at most. So I didnt think they would be bad but one of them was.
 

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Throttle body might need a cleaning, small vac leak possible.

I would mostly rule out fuel and spark since it's not hesitating under throttle.
 

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Discussion Starter #4
Cleaned my throttle body but now when I stop it revs at 1200 and then slowly drops to a 7-800 idle...how could that be? :S
 

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try replacing the auto light plugs with these ones

NGK - PZFR5D-11 and see what happens its the plugs that come with the car from the factory
 

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a. auto lights suck and almost always cause weird misfire issues.
b. change plugs anyway
c. gap plugs properly
 

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How is it aligned?
its aligned digitally via vag com. its the same diagnostic / trouble shooting / programming program the dealerships use.

its made by a company called ross tech.

but.. you can also do a mini version of it with the key..
(turn key to on position but do not start the car)
let the car sit with the key on ( should hear a faint whistle / nosie from the t body)
let it sit for about 2-3 mins. and it should be aligned on its own
 
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