impreza rough idle / power loss
 

Hi all
Wondering if you can advise me please?
Driving to work last couple days my impreza (my96 wrx jdm) and twice now ive stopped at lights and when i go to pull away engine bogs down and runs really rough! if i continue to tryand accelerate it dies but if i let off it runs rough for 20-30seconds then seems to clear :-/ any clues would be greatly appreciated!

when it boggs down, if you back off the throttle and accellerate very very gently, does it stop sounding rough? if so, probably coil packs and/or spark plugs.
It would also do this at higher revs when giving it some beans too. my last scoob did it about 4000 RPM when hard on the throttle. changed coil packs and plugs and the problem went away

Thanks for the advice i have coil packs and plugs now so ill post how it goes ;-)

Ok thanks again for the advice chap ! Spot on you were !
One of my coil packs fell apart when i removed it ;-) but to my horror i found the BODGE wiring that ive pictured ! This was the front offside coil pack wire :-( and they even cut the plug off engine side !! So i have spent some time soldering and shrink wrapping a new joint ! So after some fuchs titan oil an oil filter . Laser platinum plugs 4 new coil packs and some tidy handy work shes one happy scooby and im one happy owner ! Im now glad i brought this one to replace my classic that was written off in december :) ill get some pics up of her shortly ! :doubleup:

glad you're sorted

its shocking what u find 6months down the line!! theres always some sort of bodge makes you wonder what else has been done!! glad youve found your issue and sorted it!! mine idles down to 200 revs when hot but only when engine is off and restarted, a few revs sort it so it maight pay me to have a ganders at my coils!!

Cheers chaps it is shocking what you can find i noticed the idiots had tried to fit a manual boost controller too but gave up and had just blanked the boost solenoid air bleed pipe off :/ also with no pipe then going to the airbox resonator air was being drawn in after the maf lol all sorted now too ! Shes boosting good n strong now :-) dont know if you noticed in the pic the top rad hose has been cut in half and a joiner put in i guess for some sort of temp sensor :-/ thats to be sorted next as its bound to leak at some point ! ;)

bonner, do you find sometimes when you are in traffic, your engine revs drop lower than normal one minuite and the next time you move, they idle normal again ? if so, check and adjust your throttle position sensor. had that issue on mine although mine wasn't going down as low as your RPM

Paul, wish you had mentioned your top rad hose last week, I think I have an unused OE spare one around somewhere ! lol

yep seems to hunt its way back up like its starved air or somin? how do i go about ajusting it?? cheers

Coil packs should always be the first port of call on a 1993 - 1996 classic.
They started to become a problem about 5 + years ago, especially when trying to run additional boost.

Anyone with a 1993 - 1996 model now, that hasn't already changed them, is strongly advised to bite the bullet and fit a new set. You will be suprised by the improvement in performance.

There was an ecu pinout on jgm's site which tells you which wire on the ecu to check the voltage on and what the voltage should be with the throttle fully open and fully closed.
It's simply a case of connecting a multimeter, undoing the two screws on the TPS, the with the ignition on, you rotate the TPS a little so the meter shows the correct voltage, then do up the screws again.

What I did was use a very thin sowing needle to pierce the wire on the ecu connector, then stuck the lead from the multineter in to a crocodile clip and clipped it to the sewing needle so it didn't fall off.

You can also push the multimeter probe into the back of the connector.
If it's too fat, push a paperclip in there, then connect the probe to that.

il get on that my mates got the meter kit so il get him to give a hand thanks chaps!!


ecu located under pass footwell?

On a classic, yes. Not sure about newage but I would guess so

Yes, also under carpet in passenger footwell on a newage :)

Ah typical lol :) would just like to say thank you very much for the coil packs andy they were like new as you said and a bargain price ! Well worth the drive up to you to get them . Was a pleasure to meet you and id also like to thank you again for patiently holding onto them for me till i could get to you ! Perhaps i will bump into you again when i finally get round to joining you chaps at one of the meets :-)

no worries