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Engine misfire/backfire ?
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Old 05 Aug 2008, 11:29 AM   #1 (permalink)
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Unhappy Engine misfire/backfire ?

Hello all !!
Can anyone help me with my 98 UK Turbo. It has been stood up for a few months but started up and driven up my drive each week. Until the other day as it was starting to warm up the engine started to misfire and the revs were dropping really low. I have reset the ecu and ran a fault check (none shown, all clear). When i try to drive the car there is a serious misfire and backfire. Any suggestions would be greatly appreciated as i dontknow where to start.
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Old 05 Aug 2008, 03:22 PM   #2 (permalink)
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Re: Engine misfire/backfire ?

Have a look at the coil pack. You can remove each one and have a good look around the rubber boot. If you see any signs of cracking etc this may well be your problem.
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Old 05 Aug 2008, 03:42 PM   #3 (permalink)
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Re: Engine misfire/backfire ?

Thanks Pete. My impreza has the single coil pack on top of the engine. Have checked it and all seems okay. Any other suggestions ? It ticks over fine from cold but then starts to misfire as the engine warms up.
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Old 05 Aug 2008, 05:15 PM   #4 (permalink)
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Re: Engine misfire/backfire ?

Have a look at the MAF "Mass Air Flow" sensor. If you disconnect it and the car stalls then the maf is OK.

Link. wheres maf sensor
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Old 05 Aug 2008, 09:15 PM   #5 (permalink)
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Re: Engine misfire/backfire ?

Thanks Pete. Will try first thing tomrrow after work. Fingers crossed, as they're not to expensive are they ?
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Old 05 Aug 2008, 10:39 PM   #6 (permalink)
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Re: Engine misfire/backfire ?

Scott. I suggest you telephone Alyn Stockton and ask him for some advice. He is a .Org member, I'm sure he will try and help you with the engine misfire/backfire problem you have.

I think the MAF sensor's are over £100.


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Old 06 Aug 2008, 07:56 PM   #7 (permalink)
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Re: Engine misfire/backfire ?

Pete. I have e mailed Alyn Stockton so waiting in anticipation. I disconnected the ecu tonight with the car running and it stalled so i guess it rules that one out. The car starts,revs and ticks over fine from cold but as it warms up the revs fluctuate anywhere from 2000- 200rpm until it eventually cuts out. Weird!!!
Thanks again for your help/advice
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Old 06 Aug 2008, 08:21 PM   #8 (permalink)
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Re: Engine misfire/backfire ?

Quote:
Originally Posted by scott elliott View Post
Pete. I have e mailed Alyn Stockton so waiting in anticipation.



Have a look for a vacuum leak (rushing air sound)
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Old 07 Aug 2008, 06:10 PM   #9 (permalink)
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Re: Engine misfire/backfire ?

hi, i am experiencing the same problem. Talked to my mechanic about it and he says it mite be the idler that is faulty or injectors need to be cleaned (purged)
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Old 12 Aug 2008, 03:13 AM   #10 (permalink)
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Re: Engine misfire/backfire ?

people i need help i dunno how to post forums but if anybody knows could they possible tell me what the problem is with my scooby through a message or wateva as i am new to this site and dont know how to work it at all but baiscally it drives fine but starts driving funny if i go over 60mph and it wont allow me to go over that i can redline first then halfway through second it will play about but thats only if im flooring it but if i go throughout the gears nice an easy its still alright but again if im in 5th and try go over 60mph it will not go over that. ive been told it could be the air sensor meter (maf) could anybody possibly let me know through a private message or just let me know how to post a forum please!!!!!. cheers
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Old 12 Aug 2008, 05:08 AM   #11 (permalink)
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Re: Engine misfire/backfire ?

do check yr spark plugs at the same time.
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Old 13 Aug 2008, 12:01 PM   #12 (permalink)
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Re: Engine misfire/backfire ?

Quote:
Originally Posted by was4 View Post
hi, i am experiencing the same problem. Talked to my mechanic about it and he says it mite be the idler that is faulty or injectors need to be cleaned (purged)
Hi. What do you mean by the idler ?
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Old 13 Aug 2008, 03:02 PM   #13 (permalink)
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Re: Engine misfire/backfire ?

Quote:
Originally Posted by scott elliott View Post
Hi. What do you mean by the idler ?
i think he meant the idle valve??
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Old 17 Aug 2008, 05:39 PM   #14 (permalink)
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Re: Engine misfire/backfire ?

scoobybhp, sounds like its in limp mode mate, get it plugged in as it could be so many different sensors, are you gettin engine check light. u can try reseting ecu (disconect battery for a few mins)
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Old 24 Oct 2008, 11:20 AM   #15 (permalink)
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Re: Engine misfire/backfire ?

it seems im in the same boat as many in here....at my wits end with my scooby.
i have a uk 1994 impreza turbo with huge issues regarding running. when its cold it runs fine....warms up misfires stalls hardly drives etc....however, it runs great if you keep it above 2500rpm and on the turbo....otherwise drives like a kangaroo and like its missing at least 2 cylinders. ive cleaned the maf, checked wastegate changed plugs etc. i tried diconnecting the lambda just now as suggested in one of ur threads and the check engine light came on, reconnected it removed the battery leads and its stuck on still....and the dam thing is still running like a ford!! any new suggestions? btw, if i unplug the maf it stalls.
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