My car started accelerating extremely slow. The throttle response is terrible. I thought it might be the MAF so I cleaned the "s" out of it with MAF cleaner, but nothing! I replaced the air filter and it made no difference. Could it be that the MAF is completely shot? I ran it without a MAF and it got worse (I then reset the ecu and it went back to being super slugish). I will run fuel injector cleaner through the system tomorrow and see what happens. I suspect the timing might be off? But out of nowhere? I thought that a bad MAF would trigger the check engine light...? Fuel filter??

Any help greatly appreciated. I have a my93 L AWD sportwagon, with a brand new cat. Also the car idles perfectly.

 

You are diagnosing your car correctly.
I would change your fuel filter and see what happens.
When was the last time you changed your spark plugs?
Change your spark plugs if you haven't.

 

im gonna guess knock sensor, do you have a check engine light? when a knock sensor goes bad it will retard the timing almost all the way

 

I guess that could be a possibility, but the CEL is not on. I will install a new MAF this evening and see what happens.

 

install a knock sensor BEFORE an expensive maf

 

First off what generation impreza do you have? Does it feel like the throttle is stuck? If anything clean out the throttle body/plate before changing anything. But I'm pretty sure your due for changing out the fuel filter and plugs like the guys said. Good Luck.

 

so I changed the plugs, MAF, fuel filter, and it made absolutely no difference!? I am really starting to think that it is the timing.

Here are my symptoms:
With the car in park, i floor the accelerator and the rpm's rise VERY slowly. But when it hits approx 4k, it revs normally.

????:
Is it possible to check/adjust the timing without removing the crank pulley/cover?

so the knock sensor would also produce these symptoms?

Once again, I this for a MY93 L sportwagon with an ej18. It's Agean Blue metallic if that makes a difference

 

yes the knock sensor controls timing, when its shot it retards the timing as far as it can go

 

I see. Where is the knock sensor located on our cars?

EDIT: I just read that ej18's don't come with a knock sensor...

 

well the only way to be sure is to look for it...its right underneath the throttle linkage bolted to the block, with one bolt, its round with one wire that goes to a white connector, im pretty sure some 1.8s got a kock sensor...if you PM me the last 8 of your vin number i can look it up ( i work at a subaru dealer) and see if your car came with one