I haven't got a gauge fitted yet so this is from feel and noise of turbo whistle.....basically the turbo is not consistent at all some days it will be fine all day then others no boost at all for about 10 miles of driving then partial boost....then from now where full boost this is not due to cold or hot as sometimes its the reverese cold its fine then after 20 miles its no boost ?
Any ideas ? I have chnaged the boost solenoid, dump valve and intercooler with a mates car which was running fine till he snapped his timing belt :(
I have HKS...not sure if its system or just back box as I have never seen a CAT. But strangley I fitted the K&N induction kit and it was fine for like 3 days then back to normal inconsistent boost ?
thanks.

I'd get an AFR meter as well, & possibly knock-link or similar... could be something weird going on with the MAF (what MY?). Does it change after traffic, etc? Just thinking of heat-soak into the intercooler after bing in traffic, boost on, knock, retard, sluggish, etc. etc. Switching the ignitiion off & on again clears the ECU from not controlling the wastegate (ie letting it open on its own accord at a half-bar), but it sounds like you're scooting about more than that.
How long's it being doing it for? Have you checked for looseness around a hose all along the air inlet/intercooler/inlet manifold area?

Its been doing it since a week after I had it....only had it just over 1 month. MY94 Import WRX. I have checked the hoses they seem tight no holes etc Could it be the plastic intercooler pipe that joins the intercooler to turbo ? as I didn't change this pipe as my m8 snapped his getting it off....didn't look cracked....gasket seamed ok. Its just crazy as somtimes it wil be on full boost then next time I try to boot it like in 1 mins time then no boost or phasing in and out boost. Thinking of booking in it at my local subaru dealers but like fook am I paying thier "investigation hours".
cheers

Not sure if the problem you are having is similar to mine. Ive got an MY93 wrx, and i get boost all over the place.... doesnt matter on weather.

I can drive like a grandad all day and would know theres a problem, but put foot into carpet and it takes off, then when boosts hits 0.75 it coughs and splutters like a miss fire.

Ive changed the boost solenoid, new MAF sensor, new plugs ...and its still the same. Im thinking of changing coil packs next ...


Been quoted £50/ hr at local scoob garage to look at it

Yeah sounds similar except with mine no spluttering.....plus today it was perfect full boost all the way to work 30 miles !
But when it does mess up the turbo just doesn't seam to spool up or spoool then stop etc

I used to run an R5GT Turbo with similar problems. Turned out to be a faulty wastegate actuator and some perished hoses. I recommend checking the hoses again and if you can try swapping the wastegate actuator from your mates dead motor. I trust you are running superunleaded/optimax. If your not your ECU may be retarding the ignition. Have you tried resetting your ECU? Good luck

Cheers m8....the actuator would that be the metal arm thing that pops in and out with pressure ?
If so changed that also forgot to mention it as I didn't know what it was called :)
I run Optimax only I have reset the ECU via battery off method and its didn't seam to do any good but as I said today coming to work it was fine.......crazy thing !
Should I try getting some octane boost to get it more towards 100RON ?

I've had a similar age car for nearly three years now and unfortunately (fortunately for me tho ;) ) i haven't had any problems like what your having. I do however think that putting octane booster in will not cure it. I've run the car on unleaded (when i first got it for a couple of weeks :o ) then super, then optimax and now with octane booster and in performance terms there's hardly anything in it.... just makes the care feel smoother.

I'd be inclined to get a lambdalink and knocklink on the car and see whats going on. Do you have a boost gauge? What sort of boost are you getting?

Tony.

I haven't got a gauge but did put a temp on on it and it was boosting about 5PSi so not good but then after I put my K&N on it went to 11 - 12Psi and was fine for about 3 days then same but yesterday was not good yet today is good ?

11-12 psi is rougthly what it should be (i too have K+N), i'd have a look at the diagnostic section on this page....

http://www.jimclarkeracing.co.uk/~scoobynet/premy97.html

Check the MAF sensor etc (if you've got a volt meter) to see if electrically everything is as it should be. Were you careful with the MAF sensor when you cahnged to the K+N?

Tony.

Could the problem be the fuel ? could I have had dodgy fuel ?
I filled the tank up with optimax this time from a different shell garage so could it be the scum are labeling it as optimax and it is really regular unleaded ?
Its been fine just took it for a blast dinner time and it was fine ! so thats the only thing I noticed was I used a different shell garage to fill up. I didn't touch the MAF sensor at all left it in the plastic case as u r supposed to and didn't go throwing it about.

The fuel would have to be very ****ty as i used normal unleaded when i first got the car and it 'felt' fine.

Just see how it goes from now on.....

Tony.