Bad idle misfire and loss of power

[my95tsi]

Ok I've searched and searched and i can't find anyone with the exact same problems as me. For the past 3-4 months i've been having some major idle issues with my car. When it was cold outside my car would act really funny. On a warm startup my car would idle really low and shake like crazy, about 20% of the time it would die. When i revved it up while it was idling low, it would sound like popcorn, like my car was misfiring. This problem went on forever but cold startups would be just fine. It was only after i restarted it that it would do this. Now that the weather has gotten much warmer my car has never done this again, but now my car seems to misfire at idle. I don't get any misfiring while driving at all. My car does seem to backfire pretty loud from a 1st to 2nd shift and sometimes 2nd to 3rd. At idle you can feel my car shake as it pops through the exhaust. My rpm's don't change at all but you can feel a deep rumble and pop every few seconds as it idles. It was never like this before and it feels like i'm in some race car. My car does seem like it's a bit sluggish off the line and almost like i lost torque when i downshift. But i don't have a misfire while driving, which is strange. I don't really know what could cause this but the misfiring at idle is very noticable when your inside the car but the subtle shaking, when your outside you can hear the different tones through the exhaust.

 

[DSM90AWD]

Have you checked for boost/intake leaks? The sputtering at Idle seems to me like you're pulling in unmetered air and running lean. I assume you're BOV is connected to your intake?

Other thoughts: change your fuel filter if old (or of unknown age) and make sure you are running the correct NGK plug, check for exhaust leaks.

 

[my95tsi]

I did a boost leak test and found one minor one and fixed it. A vacuum hose connected to the intake manifold was leaked so i put a clamp around it and it's fine. I tried to chnage my fuel filter the other day but i ws unsuccessful. The bolt wouldn't break loose even with pb spray on it. It didn't want to force it too much and snap the fuel line. The whole assembly moves way to much when i try to loosen the bolt. I don't have any exhaust leaks that i know of but that would only cause me to backfire and not cause the bad idle.

 

[DSM90AWD]

I tried to chnage my fuel filter the other day but i ws unsuccessful. The bolt wouldn't break loose even with pb spray on it. It didn't want to force it too much and snap the fuel line. The whole assembly moves way to much when i try to loosen the bolt.

If it's the same as the 1G housing.. you'll need two wrenches, one to hold the housind and one (preferably flare) to turn the top/bottom fuel line bolts.