Hi All. I'm hoping that I can get a few thoughts from everyone. I have a 2004 2.5T with 200K miles.It has been handed down to my son, and is his daily driver. I am quite savvy with repairs, and am capable of doing just about everything that this has needed over the past 8 years. He came home the other day and said the car was acting up. I Took it for a drive last night, and found that while under relatively heavy throttle, and while under boost, or building boost pressure somewhere around 2500 rpm the engine flutters and stumbles like it's missing badly. I immediately backed off the throttle and then got back on it, and it seems to get better, but it doesn't go totally away. The ignition coils, and boost control solenoid have never been replaced. (it does seem to have developed a semi-rough idle as of late). I was able to get it to throw a CEL, which he hasn't seen come on yet. A friend is sharing his super fancy scanner tonight, so I can pull codes. Once I was back in the driveway, I was able to reproduce the miss/flutter by pegging the brake pedal and getting on the throttle.

Everything that I have experienced is leading me to believe that it's either a boost or fuel delivery issue...but maybe ignition...Maybe fuel pressure regulator?

Your thoughts????

 

You need to get codes pulled. But by the sound of it it's either the turbo control valve or coils and spark plugs. The only way to make sure is to pull codes

 

I wasn't able to get my hands on the super fancy scanner last night, so I did a few things. First, I cleaned the MAS which had a fair amount of residue on it. (I've had the car for about 130k miles and have never cleaned it). I checked all of the coils and plugs. The plugs were fairly worn, but I've seen much worse in my days. All were over gapped at nearly .055, so I regapped them to .030, the manual stated the gap should be .028 -.032 so I went right in the middle. (I will be getting new Bosch platinum plugs tonight) The problem seems to have been corrected....for now.

 

Mine had the same symptoms, the code was about plugs . replaced the plugs and all is fine.

 

I never got the chance to pull codes, so I went the old fashioned route - using my brain! After pulling out the plugs and finding the gaps all out of whack, I simply replaced the plugs and whalla! Symptoms gone.