Hi guys,

A bit about my car, Its a MY95 UK, running a TD05 turbo, FMIC, Polar Performance Chip, HKS superdragger exhaust, full decat, induction kit and a dump valve.

Ive not owned the car long, but it has never boosted as strongly as it should. When accelerating hard there is an initial feeling of hesitation, followed by boost (which doesnt come in very strong, but is boosting to 17psi), followed by hesitation then boost again. The best way to describe it is like the boost is coming in waves. It isnt hitting boost cut, as with my previous cars i know that boost cut is rather violent, this isnt, it just doesnt feel right.

Ive changed the coils, which has made a slight improvement but not much. I have tried using the std dump valve which made no difference. I have changed the knock sensor which resulted in no change.

Ive driven a few scoobies, and i know how mine should feel, so i know for sure its not normal for it to feel like this.

Any suggestions guys???

 

It could be overboosting, what gears does this happen in?

Tony

 

Hi mate, Its happeneing in all gears, but more noticable in 1st to 3rd. I dont think its over boosting as its boosting to 17psi, which is what the PP chip has set it too.

 

Also, changing from 2nd to 3rd on full boost, i am getting a backfire, not so much of a bang, more of a boom. It vibrates through the whole car.

 

just a thought wouldnt want resetting up or faulty boost soloniod or maf just a few but im sure u no more than me

 

Hi guys, Car is still the same.

When it comes onto boost, i can see the boost on the gauge, but it doesnt seem to accelerate any faster.

My gf describes it as if the car is trying to be pulled backwards, its holding back that bad.

Any ideas??? Does anyone know if the polar chip is set up for a fmic? could the fmic be my problem?

 

AFAIK the original PP chip was not mapped for FMIC. The ones now being sold by Major Sarcasm, i don't know, but if that is where it came from, then you would be best talking direct to him or dbp, who i believe does the map,iirc.

There have been a few with boost problems after chipping. The fault eventually seems to rear up as a code 45, which can be any of the 3 components on the BCS bracket. This 'i' think is due to the increased boost finishing off the well worn 14, 15, 16, 17 year old boost sensors. It can, it seems take a while for the code to show, ie the sensor to fully fail.

 

Have you just fitted the chip or has it run fine with the chip.

Had a 95 wrx and bought a polar performance chip for her.

You are right in saying it is not mapped for a front mount as i asked if this would benefit my car by fitting one the guy told me no if anything go for an STI Top mount??

My Car had the folllowing and run perfect:

TD05 Turbo
Full De-Cat Exhaust system
Walbro fuel pump (Was told to fit this before the chip)
Dump valve
Induction kit (They recommend panel filter)
Standard fit intercooler.

Hope you get it sorted out not nice when your impreza is misbehaving

 

your quite knowledgeable on the old failing boost matter now steve

 

Thanks for the input guys. I am going to buy a std intercooler and put it back on.

Upon investigation yesterday i did find a split pipe, the one that comes from the turbo to the MAF sensor. But i wouldnt have thought that would have caused me these problems. Im going to replace that today aswell.

Cheers

 

The chip has been fitted for a few years, Ive only recently bought the car with the FMIC already fitted. On the test drive it wasnt half as bad as it is now, But even then it wasnt 'normal'. I was informed the coil packs were cracked. I have since replaced them but the problem still remains. I will put the std intercooler on and go from there.

 

just as a general mark what should MY01 boost at (max) in bar please

sedge

 

Approx 1-bar

 

cheers m8

sedge