Hi all,

im new here, so please be gentle.. :-) i have recently purchased a 94 GF8 WRX that came complete with a blown engine, after rebuilding the engine (it had blown a big-end bearing) and dropping the engine back in, upon running it up and down a road a couple times it seems rather laggy down low, between around 2-3.5K RPM, i had previously had use of a later model GF8 (around 97 ) and this one seemed to be allot more responsive down low. given that i had not driven the vehicle before and have never driven a earlier model WRX before, does this sound correct?

also i have put a good condition seconds hand turbo on the engine, as the one that came with it was very messed up. i did notice that the Wastegate Control Solenoid valve has one of its pipes connected to nothing but the atmosphere, im assuming as the previous owner had put an aftermarket intake pipe between MAF meter and the turbo, that maby this connects here? please see attached pics, the pipe im referring to is pointed to by Green arrow, going to Wastegate solenoid (pointed to by pink arrow), im prity sure i have the Pressure exchange solenoid connected properly (blue arrow), and (orange arrow) is Pressure sensor correct? could anyone suggest a place to connect this hose to?

http://imageshack.us/a/img200/7669/h2qk.jpg

also (another attached pic) there is another hose that seems to go nowhere, that is coming from two pipes with one-way valves in them (light grren and dark green arrows in pic 2), off the front right side of the engine (drivers side) did this go to a carbon filter that no longer exists in my enigne bay? is it going to be an issue if it connected to nothing? (pink arrow in pic 2)

http://imageshack.us/a/img819/6405/t2l9.jpg

 

What boost does it make full throttle at 2000, 2500, 3000, 3500, 4000 rpms? Once you have this information you can eliminate boost control issues.

 

Hi boosted, thanks for the reply. i am yet to get these figures for you, the vehicle is not fitted with a mechanical boost gauge nor do i have one, but i will get these values for you.

however.. i have been driving the vehicle for the past few days now and have become a little more familiar with it. it feels like when its on boost (or atleast creating a nominal amount of) around 3000rpm and above the engine feels ok, from 1500-2800 it has a weird stutter and feel like its missing or not getting the correct mixture. this problem is more evident when the engine is warming up and/or cold. thinking about this i went and pulled the codes from "read memory" on the ecu and got:

44 - wastegate control solenoid
23 - mass air flow meter
24 - idle air control solenoid

thinking that these could be sitting there from a previous event i attempted to clear the memory (conntecting both read memory and test mode connectors under the dash - the black connector(s) and the green connector(s)) and full throttle, then off, then start engine and drive for 1min at > 11km/hr. upon driving it (with these connectos still connected) and after approximately 1min i got the code: 32 - oxygen sensor. coming from the engine check light. parking the car up and then doing a "check memory" (just the black connector) on the car still yeilded the same codes as before: 44, 23, 24. but no new ones or no 32. so im starting to think - i dont think i would have malfunctions on all MAF, idle air control and wastegate. but i am thinking that because the vehicle runs worse when cold AND still has a miss and is very flat around the 1500-2800rpm mark when warm that the Oxygen sensor could be damaged. and/or the heater may not be working at all (as problem is more evident when engine is cold). what are your thoughts?

ill take a reading from the O2 sensor with a multimeter later today and see what i get back.

Regards

 

Ok so just took a reading now from the White wire to GND from the Oxy Sensor and have it sitting on 295mV, doesnt move from there with increase in RPM. ive heard that the voltage should fluctuate between 200-700mV a few times a min, is this correct? this was done while the engine was already at operating temp and no load (parked). this is the 3-wire sensor. other two wires must be for heating?

 

Any joy with your problem?

 

Not really, the problem seems to be slightly better, BUT. i did replace every single sensor on the engine, Idle-Air, both temps, MAF, Oxy. i can only put i down to the computer. i even tried a different computer thpugh and no luck. it now runs like a$$ in the morning or from a cold startup, when warm it runs ok but still not 100% how you would expect still fart and coughs some times. i did however put that spare plug down to the Cat-converter being removed in the exhaust system, after i put a 2.2K resistor bridging that line i did notice a difference from it running rich to running better and using a normal amount of fuel. however i cant seem to find the running rough and "spluttering" when cold. it almost sounds like a miss but ive done the plugs, tested the coils for resistance etc etc. tested the wires. im really thinking it could just be a computer issue. and the codes after i clear them dont seem to go away and refer to sensors i have replaced with good sensors.