Full boost no power after 4000RPM

[maxbo0st]

(Fully stock 1992 eagle talon tsi awd) When at wide open throttle the car feels fine until 4000RPM but after that theres no power. the check engine light also turns on when warming up the car.after warm up i turn the car off and turn it on again than the check engine light is gone.after about 5 mins of driving it turns back on again. any help will be appreciated thanks in advance

so far i gapped the NGK plugs.checked the timing.replaced MAS sensor

 

[laserspeeddemon]

Does the car sputter or just simply slow down? Gives us more specifics on the sound/feel of the car when the problems occurs.

 

[maxbo0st]

no sputter or turbo lag when driving and everyday when i first start the car it has a hard time starting and stalls all the time and when i try gassing it to keep it on it sputters, when its warmed up its fine again. but when im regular driving under boost its fine shifting around 3000RPM but when i floor it even under 4000RPM it feels like its an all motor but i can hear the turbo spool. i also checked the compression it was 135 across the board. any guess on what sensor might be bad cause CEL is on. i need this car running right before snow falls.

 

[mhuffman]

I have a similar problem. Above 4500 rpm's, my car stutters like a fast rev limiter and i have NO MORE acceleration. Below 4k, it pulls strong just as it used to.

 

[Silver 95 GST]

Bad running under WOT might be ignition related. I suggest replacing plugs and wires. Make sure you are not using the platinum NGK's. This link can help for picking plugs/gaps.

http://www.dsmtuners.com/forums/frequently-answered-dsm-questions/233421-spark-plug-faq.html

 

[dsm03]

Agreed. My car did that after 4 1/2 thousand rpms it was do to spark plugs, get the regular NGK's. If you guys search the forums a bit you ll find the part #... sorry dont have it off hand.. And if it doesnt work it still a cheap investment and trial/error.. Who knows might fix it..

 

[crimsondragon]

any guess on what sensor might be bad cause CEL is on. i need this car running right before snow falls.

Who the hell knows? Why not just go to Autozone and have them pull the code instead of us second guessing your little CEL problem?

 

[talontd92tsi]

Sounds like a knock sensor issue to me.

 

[maxbo0st]

i found out the CEL it was my Coolant sensor. but i still have issues on the performance after 4000rpm. thanks for the replies guys as soon as i get new plugs and wires i'll get you guys updated.