leeS2

took a 93 wrx in chop today and suffers a heavy miss type kangaroo on boost, is worse in higher gears, is somewhat better if progressive on throttle but still appauling, havent even started to look yet just asking for some pointers, oil looks old so hoping something simple like plugs etc, drives fine off boost and as enters boost is fine, but say throttle it in 5th on motorway boosts ok for few secs then hessitates badly.

car was imported 8 month ago and has only done 4k since.
have good mechanical knowladge but as far as scoobs are conserned im in the dark.

cheers

jameswrx

iTrader: (4)

coil packs will be favourite I reckon.

My 94 wrx was doing this, changed them and it's sweet now.

leeS2

expensive?

edited to also add, it almost boosts perfect in first gear, puul away and floor it in first and pulls very well, couldnt be a overboost also could it? say a twonk was messin with the actuator to try to raise boost

[Edited by leeS2 - 2/27/2003 7:38:15 PM]

leeS2

come on chaps i wanna start investigating the fault tomorrow

jameswrx

iTrader: (4)

If it's overboosting then you'd get fuel cut, this is really heavy, not like a missfrire, when you hit fuel cut it's like slamming the brakes on.
If it is like this then yes the actuator messing would cause it, especially in higher gears(more boost), if this is the case the 'twonk' must have wound the preload too tight on the actuator. Crack the nut off the actuator arm, take c clip of and pull actuator arm from wastegate lever, then wind the end of the actuator arm out on the thread until it reaches a distance that it just fits on the wastegate lever with a little bit of effort.

Coil packs also usually cause a missfire in the lower gears and what i read now sounds more like fuel cut, unless it's not heavy?

coil packs are about £48+vat each btw

leeS2

yes its like the engine completely dies for a sec then pics up then dies etc, throttle off a tad and she's fine,
EDITED TO SAY:
it isnt a fierce shove ya into the windscreen tho, thinking bout it car may posibly miss at the same time as the cut out and not just shut off and pic up if ya know what i mean

doin some quick reading on here i want to :


1: clean boost solinoid, how and were?

2: spark plugs, sound like a right workup to get to, havent looked yet

3: spose lenghten the actuator rod by one turn after trying above to see if helps, if not replace to original setting.

anythin else? and how?

[Edited by leeS2 - 2/27/2003 9:13:32 PM]

jameswrx

iTrader: (4)

If it's that hard its the fuel cut so


1) LHS engine bay near strut area facing you bolted to the chassis, cylindrical solenoid, with 3 small pipes attatched, 1 from turbo inlet housing, 1 to actuator and 1 to inlet pipe. Take all the pipes off(remember fitting) and spray carb cleaner in the top hole.

2) don't bother

3) You want to give it a bit more than 1 turn for a try i'd say, why not undo until it just needs the slightest effort to place onto wastegate lever?

edited coz i got me numbers wrong

edited again coz I've forgot what colour the solenoid is think it's just goldy colour?

[Edited by jameswrx - 2/27/2003 9:20:45 PM]

[Edited by jameswrx - 2/27/2003 9:26:58 PM]

leeS2

be ok if i had a bloomin boost guage the i could wind it right back, atleast if i say turn it two whole 360 degree turns i can restore it easily if its not the problem

redwrx

Ive got MY93wrx, and had problems with it missfiring underload, mine turned out to be 'plug gap' ... they need to be 0.7mm.

Driving like a grandad mine was fine, but as soon as i booted it, it coughed n spluterd bigtime.

Coils packs are prone to weakness an failure, as is the boost solenoid, and MAF sensor ..

1.Cheapest thing first id say, check you plug gaps.

While the plugs are out, try next one .. visually inspect the rubbers on the end of the pack, the rubbers either crack or go very brittle ...be careful when youre removing them...undo the bolt the holds them in , but dont pull it all the way out, then try pulling the coli pack to release it, and then undo the bolt the rest of the way ..if you take the bolt out first you run the risk of damaging the rubbers

2. if you have a test meter, measure the coil pack resistance .. follow the lad from each coil pack, back to the first connector, open

3.Boost solenoid can be taken out and cleaned with 'carb cleaner' ...

4. MAF sensors do fail, but i dont know of a check you can do ... so i wouldnt go along this route just yet.

Frank

leeS2

ok update

firstly the oil was seriously overfilled

couldnt work out how plugs come out

wasnt sure what exactly was the boost solonoid, theres a big black plastic one and a small metal gold coloured one

oh and it nearly sent me into the windscreen today so gotta be this fuel cut you lot are goin on about, although i still dont think the chap has been fiddling with the actuator rod, he doesnt seem to have a clue about cars



[Edited by leeS2 - 2/28/2003 6:18:25 PM]