Hi Guys,

Yesterday my car developed a problem.
whilst the car is fine below 3500rpm after that when boost kicks in I can really hear the car starting to suck in air. Then the car sounds like its mis firing (coughing and spluttering) if I take my foot off the accelerator pedal and let the revs drop below 3500 it runs fine again.

Car is wrx sti 1996 with various mods including K&N induction kit tdo5 20g turbo. Apexi ecu with power commander and avcr. Denso 550 injectors. FMIC. (ful spec in the link to my car on my profile)

I looked at the avcr when the fault starts to happen and boost is around 0.22 bar so its not over boosting. fuel cut is set at 1.5bar

had new plug only a couple of months ago.

Couple of suggestions that have been made are a sensor somewhere possibly MAF or a pipe split or come off.

basically what I am asking is for suggestions as to possible causes and how to test those theories.


Thanks
Shaun

 

Definately sounds like a boost leak. Best way to test is get a solution of soapy liquid and water in a squirty container, douse all the hoses and hose clips with your soapy solution, rev the engine by hand at the throttle body and watch for bubbles.

What you describe is very typical of a sizeable boost leak.

 

I have just had a quick look during mylunch break and found the one of the pipe clips on the intercooler to turbo has come off so I am now asking everyone round here for a ten mil spanner to put it back on.

will let you know the outcome.