Hope you can help me solve a problem, I have a 94 WRX that doesn't seem to be performing as it should. We flooring it in 4th or 5th, it just doesn't seem to pull like it does in 2nd or 3rd. At 80mph in 5th it doesn't really seem to pull at all. My focus TD is quicker. There is also a slight misfire on tickover. The spec of the car is as follows:

Cat back Mongoose Exhaust
Pipercross cone filter
Dawes Device
Bosch Coil Packs
Champion plugs gapped to 7mm (although i have some pfr's to put in)

Boost gauge reads 13psi.

I have read loads of threads on here about the MAF failing, could it be this?
I haven't done an ECU check yet, will do this tonight.

Any ideas?

 

Without driving in the car the problem sounds a bit vague. To me it sounds like maybe the ecu has retarded the boost. Did u over rev it recently or overboosted ?? So check the ecu and see if there are any error codes ?? If it is so simple then u just need to reset the ecu ....

leeps

 

Yes the car has over boosted recently as I had a decat downpipe on, but had to replace due to the MOT. Spent some time on my back last night trying to find the black connectors, managed to find the green ones but not the black, will try again tonight now my back has stopped hurting.

 

Tried disconnecting the MAF sensor while the engine was running, the car nearly died but revved up again, then sat there hunting, this to me would explain that the MAF is working. Perhaps?. While the plug to the MAF sensor was disconnected I looked for the CEL, no sign, on pulling the dash out there was no bulb, obviously the ****** who had it before knew of the problem so removed the bulb to sell it. So having replaced the bulb, the light flashed the following codes.
22
23
42

I though that the light should remain illuminated until the black connectors are plugged together, poking around under the dash i found the connectors already connected. Pulled these apart and the CEL remained lit. Plugged in CEL flashed. So followed ECU reset, but when both green and black are plugged in and the car started only code 22 flashes. If i recall if you plug the black connectors together this is a historical error. Whilst plugging the green ones together is the last error the ECU has seen. So it appears my knock sensor is knackered.

Are they easy to replace?
Anyone know the part code for a 94 WRX?
What effect will it have on the car, bearing in mind I have had the car for over a year now?

Your help is much appreciated

 

Drove the car this morning, no CEL light, once the car was warm the CEL light comes on, haven't checked what code is coming up, but suspect the knock sensor.

Any ideas on how to check the knock sensor?

 

It could be anything really
A bad tank of fuel will not be very good for your car (i take it you run 97ron plus octane booster to gain the 100 ron a WRX needs?).
A missfire could be a coil pack?

Tony

 

Scary mate, very scary. Your MAF sounds like it's doing what it should be. You didn't state whether you had a knock link or AFR fitted? What worries me is if the previous owner removed the CEL bulb, knowing there was a problem, what other stupid things did he do? Like running it on standard 95RON unleaded for instance, or running way too much boost... doesn't bear thinking about.

 

Tell me about it, still if its been like it for a year, I thought it would have gone by now .

Perhaps its time for some specalist advice.

 

Have checked the knock sensor tonight, when cold it read 560ohms, once engine had got warm it wouldn't read at all. Have now removed knock sensor and found that readings are all over the place. Looks like I need a new knock sensor.

Do I have to use the original if so waht is the part number. Or is there a bosch part that will fit?

 

I have found and fixed the problem on my car, it was the knock sensor, managed to get hold of one from Midland Impreza and installed in the at weekend. What a difference the sensor has made, pulls strong in all gears. Well chuffed.

 

Good man, glad you're sorted.