Ive a 1993 wrx import. the car idels perfect and drives fine but as soon as you start to come under boost it feels like its holding back and slightly missing. i have a afr gauge fitted and it drops rite back down the gauge when under boost sometimes, sometimes its ok and reads rich like it should.

only mod to performance wise is a full hks exhaust.
i have done the following to try to overcome the problem:

New plugs, maf sensor, lambda sensor, tried another boost solenoid, octane booster, av had it on the computer at my local suby garage(no problem codes) av tested the coil packs, all outputs fine, only thing else i could think of was the knock sensor may be faulty???????

am at my witz end with this any help would be much appreciated.

cheers guys.

 

how have you tested the coil packs.
if you have just measured the resistance, this doesn't really help.
check the tips for cracks under the rubber boots, it sounds like there knackered to me.

 

checked for that too, they seem really fresh, this wouldnt explain the afr gauge reading would it??

cheers

 

Sorry to jump in. I have had a similar fault, mine was holding back and felt like fuel cutting. I doubted it was the coils but went for it. They arrived today and problem solved! Im used to having a missfire on 'normal' cars, but on a scooby it behaves like this it would seem.
I looked at them closely when I took them off, and no cracks, they looked pretty good.
£200 but well worth it.
Good luck.
Bod

 

As mentioned on my Frequently Asked Questions.
Cracks are the obvious sign, but they could still be weak.

 

I know this is no help but my year 2000 uk spec has exactly the same problem so i'll be keeping an eye on your progress

 

thanks lads i know what your saying, just scared of going and spending £200 and the problem not being solved, you know what i meaN. Still need to get to the bottom of the running lean issue, anyone got any thoughts on that?

 

Why not see if anyone on here is lives close so you can swap a good set over to rule that out?

 

yip think im going to have to try that aswell. so fekin tedious! lol

 

Hi mate
im having the same problem, its been like it for about 2 months now and iv changed everything like you have and even the coil packs. checked the gaps on the spark plugs like 15 times now but still wont boost over 0.8 bar (with my AVCr off)
could you drop me a PM if you find out and ill do the same to you.
i think it might be my cam belt slipped a tooth but i still need to check that whn i find someone to do it for me.

Cheers
Ben

 

Hi ya chaps don't know if this is any help .but my scooby was holding back .IE juddering as it went along .some times at junctions it would stall .or Even more scary half way across it .and idling roughly .1 day didn't start at all .after a weekend checking everything turned out 2 be fuel pump .about a hours job to change it .runs alot better now alot stronger when give it some when the wife ain't l@@king lol PS it's a walbro fuel pump £84 quidish

 

hi ben, if your ra has the same boost limit as mine as standard then it wont boost over 0.8bar, is it holding back all the time or just every so often?
wot type of plugs are you using, 6s or 7s? and were the coil packs you tried brand new?

orgazmic,- know wot your saying but its not the same kind of symptoms as were getting i think, i have a walbro in mine as it it is. cheers for the input mate

 

Hi mate
well i have 7s plug wise and as far as i know the coil packs i brought were brand new.
it will reach over 0.8 bar boost it just really doesn't like it.
it holds back all the time apart from when the engine is cold, not that i boot it when its cold all the time.
just soo confused what it could be.

cheers ben