flip_paint_impreza

Hi

I've got a '95 WRX import Impreza and got a slight problem I was wondering if anyone knows how to cure?

Sometimes when accelerating hard from a standing start it will suddenly feel as tho u've just hit a brick wall and it seems as tho it hits like a cut off or something before it reaches the rev limiter, what would be causing this and how can i cure it??
It also sometimes when crusing along and if i put my foot down sometimes it feels like its holding back slightly - dunna if this is related??

Any help will be much appreciated

Delboy2

Sounds like you could be either seeing overboost or you may have a coilpack/s breaking down. Do you have a boost gauge fitted, if so what pressure are you seeing? Does the hesitation mainly occur in high gears (3rd/4th/5th) when on full chat?
What fuel are you using and has the car had any aftermarket goodies fitted?

Cheers

flip_paint_impreza

Boost gauge is showing 12psi - the uk spec i think run upto 10psi, didnt know with it being an import that the boost might be set at higher spec?
run the car on optimax fuel so hopefully shouldnt be that. Only aftermarket stuff fitted is a piperX induction kit, blitz down pipe, magnex de-cat pipe and scorpion back box. Would it need setting up with these aftermarket stuff fittied?

The hestitation happens in all gears, but not all the time only from time to time and only if you've got ur foot right down too. The bloke i baught it from said that he had it checked but was told there was nothing wrong but i cant see its right to be honest.

Delboy2

The boost on a UK Scoob of similar age is around the 11.7psig mark whereas the JDM version runs about 12.7psig.
The hesitation is likely to be biased towards a coilpack breakdown but it may be an idea to check to see if the ECU is storing a particular fault. This procedure is shown HERE With regards to the modifications it would probably be wise to fit a Knocklink (available HERE ) to keep an eye on detonation as your car will be set to run on 100RON fuel whereas atm you are running on optimax alone which is 98RON which will make the engine more susceptable to DET. The addition of an octane booster will also help to prevent this but ultimately fitting a Scoobyecu shown HERE would enable you to run the car on optimax safely plus additionally gaining power due to the revised igniton/boost/fuel maps.

Cheers

brian.c

My 95 wrx done exactly the same ,like hitting a brick wall ,it was a coilpack in my case and had started to hesitate again a couple of months back ,it would always be there when there was dampness in the air ,sprayed WD-40 on all coilpacks and problem hasn't re- appeared

Brian.

Johnny sti

Hi
I have a 1993 wrx doing the same thing. Where is the coil pack on the car?
I also noticed tonight outside tesco that after waiting for my Doreen to do some shopping (about 20 min) that when i drove off for a while, it was like it was pushing 50ft of water out of the way. It didnt make any changes when i put my foot down. After a while, it went away.
Would this just be where i was sitting with the engine on for about 20 min the hot air in the intercooler?
Johnny

Delboy2

You have a coilpack per spark plug, if you take a look at this piccie by JGM you can see a black unit directly below where its says '4 CAM' on the rocker cover, this is a coilpack and you have 4
The flatness you felt after sitting with the engine idling was likely to be the Intercooler Heatsoaked.

Cheers

Johnny sti

Ah brilliant.
So do i spray in the black plastic thing of/and the spark plug if its visible with the pack off?
How much of a mission is it to do?

Johnny

Delboy2

If you look HERE JGM has given a guide on how to change the spark plugs which will be near enough what you will need to do with regards to access and coilpack removal

Cheers