Hi, Long time since we have been on here, but we need some help.



1994 L Impreza WRX (JAP IMPORT)
Aftermarket front mounted intercooler


On hard Acceleration:
1st Gear, Perfect
2nd Gear Perfect
3rd Gear Cuts out
4th Gear Cuts Out
5th Gear Cuts Out

Engine/boost cuts out(If you didn't have seat belt on you would almost go throught the windscreen.

Only on accerating hard this happens, it cuts out sort of when the boost is at its peak point.

Boosting at 0.8/0.9Bar Max


We have already changed:

Coil Packs
Boost controller solonoid
Found wire fault(Rectifid)
No Fault codes found
No brake down in plugs, all checked and ok.
Standad ECU, All showing to be ok on the computer

 

Also Changed :
Throttle Body With TPS, All set up
Swaped ECU All ok
MAF Sensor all ok
All vacum pipes all ok

 

Changes:

Boost pressure sensor

 

Put fuel clenaing in

 

try a fuel cut defencer... that will stop the ecu from cutting the boost.
You seemed to have already done all the usual problem areas.

*****

 

Have you opened the ECU to confirm it is standard?

Cheers

 

Sorry to be dum, what is that and where does it go

 

check all of the boost hoses for cracks or splits, check you have not over filled the oil. Definalty sounds like its overboosting. maybee be a loose actuactor rod or knackered diaprham?

Andy

 

All Checked the above, all ok. Anything else

 

Ecu is under passenger footwell.
Its defo overboosting.
It difficult to say on here.

 

Whats difficult about saying on here, SORRY

 

What he prob means is its hard to diagnose the fault without being in the car. Sounds like fuel cut your experiencing. Do a search on here for fuel cut and that sould help you out

 

Hi,

I think what Delboy was getting at is, it may be worth checking if the ecu has been modified.
look inside the casing for any evidence of an extra circuit board fitted or piggyback ecu wired into the standard one.

 

Check fmic for splits on the welds, ( just had this on mine ) re-welded now and fine,

 

Check bottom hose from boost control solenoid. the one that returns to the main air intake expansion box.
There should be a brass restrictor inside, with I think a 1.25mm bore.

Alot of Jap cars come in with these removed, as an attempt to achieve more boost. Some get away with it, but a decat normally highlights the problem due to the quicker spool-up.

 

id say check all your spark plugs 1st before you try anything else

 

put some clamp on the end of the vaccum collection. Vaccum hose normally expand under high heat. This could be causing it to boost spike and fuel cut.