running isues

[SCOBBYMIKE]

hi all iam new here i have a 95 impreza turbo problems again when new engine was fitted first of all it run rough lumpy when reved then sorted it self out every now and again it would do this but i would stop and wait 15 mins and then car would run fine again but last week this wasnt the case i started car up got bout 5 mins away from parents house car felt a bit slugish anfd then the rough running came back seems like a missfire so i cruised home very slowlyand hasnt run right since then
i have done commpresion test all cylinders 145
checked coils and plugs 1 coil was cracked replaced that
checked all intercooler pipes etc
oil level is fine
none of above solved my problem so
only thing i have found is if i diconnect maf it wil idle bad BUT lower rpm is smother till u get to 3000 rpm then rough running is back could this be my problem as i am low on money and need car to get to my new job
thanks guys has any1 had same problems il give anything a try its just buying new bits i wana be sure before i spend. also when maf discnncted car does stall but nothing happens when i dissconnect lambda sensor any ideas are welcome thanks all

[ScoobieWRX]

First of all you should be checking to see what error codes are coming up. If it is running that bad there must be something showing up. Not necessarily via the check engine light as not all DTC's will light one up but there may well be errors showing when you do error check. Before you go blowing money on stuff that doesn't need changing do the below procedures first....

This is the procedure: http://www.scoobypedia.co.uk/index.php/Knowledge/R...

This is what the codes mean: http://www.scoobypedia.co.uk/index.php/Knowledge/S...

Good luck with that.

[SCOBBYMIKE]

hi mate thanks for that i didnt know this was possiable i will try tommorrow do you know if the green should also be coonected thanks mike

[ScoobieWRX]

To check for Error codes you just need to connect the two Black connectors. You would only connect the green connectors together as well when you're doing an ECU reset.

Here's the reset Procedure: http://www.scoobypedia.co.uk/index.php/Knowledge/E...

[SCOBBYMIKE]

hi mate ecu read brought up no codes only ok flash so ive elimanted sensors right any other ideas guys thanks

[ScoobieWRX]

Other things that may be faulty are spark plugs or Lambda sensor, and possibly crank sensor may be playing up. You may well have a faulty MAF sensor, it's hard to say without seeing the car in person to diagnose what's going on.

Every man and his dog can throw answers at you and they can all be wrong. Long distance diagnosis is just a guess at the best of times and the fact you are low on money means you can't even get a garage or specialist to look at the car and diagnose the problem because they will charge to diagnose/fix it.

If i were low on money i wouldn't have bought a Subaru for my daily commute to work. They can be pricey sometimes to fix and they suck when it comes to fuel economy.

[SCOBBYMIKE]

i know they are prficey i was thinking of selling but i dnt want to sell running like this iam going to put new plugs in and my mind was on lambda sensor or maf but i was told maf sensor discoonect when running it should stall and it does so they said it was fine i really appreciate your help ive been on subaruimpreza.org for last 4 weeks now and now iam getting some where nobody told me about manually checking fault codes if i got a vidio would this help thanks mike

[ScoobieWRX]

Whereabouts in herts are you?

ETA: The reason i ask is because i've got to be in Luton tomorrow afternoon and depending on where in Herts you are i might be able to swing by in the morning and take a quick look.

Edited by ScoobieWRX on Wednesday 28th November 18:14

[japgt]

why dont you join a loacal owners club if you havnt already, and ask on there if someone would be willing to help you by coming and having a look at it, most local owners clubs have a resident mechanic who is knowledgable enough to diagnose something like that for you, chuck him a tenner for a few pints for his time.

[SCOBBYMIKE]

hi guys iam in bricketwood st albans just off jct 6 m1 mate i have changed plugs today and still haveing no luck iam sure the maf is the cause i think put money cant allow me to change this until i know of a chance other thing is rembered when brought this engine it had a diffrent inlet on it could this cause concern as i put my old one on this engine thanks

[ScoobieWRX]

What induction are you running?

Is it a cone filter sat in the engine bay, is it a Flat panel filter in the factory airbox, or is it a cold air induction kit in the form of a cone fitted in the space between the inner wing and outside wing?

[SCOBBYMIKE]

hi mate its a foam dome shape filter where air box orignally sat this was on car when i got it

[SCOBBYMIKE]

this filter is similar found on ebay looks cheap

[ScoobieWRX]

What was on there before??

[SCOBBYMIKE]

no idea this is whats always been on car since ive owned it mate thanks

[ScoobieWRX]

Big air filters like that can cause running issues and the ECU really needs to be remapped to make it run right. Usually the MAF sensor needs recalibrating to reflect the correct airflow of the larger filter. You'll find your engine may be running a bit on the lean side possibly. The MAF sensor can still cut out when you disconnect it even when it's faulty.

Another MAF sensor may be your only way forward if you think it's knackered. I would try borrowing a MAF sensor from someone first before you go splashing out. Buy a used MAF sensor if you can, they are not cheap new. Look on eBay and try Grade A Subaru.

[SCOBBYMIKE]

excellent this may be my next call althogh i dont know of anyone with a maf i thought of replaceing this filter if maf is knackered is it possiable it wont throw a fault do you not think the inlet will make much diffrence thanks mate

[SCOBBYMIKE]

hi mate if you do want to pop by tommorw il leave my number its 07927056914 thanks for all ideas il keep you all posted

[ScoobieWRX]

A faulty or dying MAF sensor doesn't always throw a code.

If i can make it in the morning i'll let you know pretty early but it depends on how busy my phone is and who's screaming for me first thing.

[SCOBBYMIKE]

good man i really appreciter your help if you can make it or not noworrys you have been a great help mate il be about got loads of bits on car to sort out previous owner bodged it right up silly things like no rubber in top of windscreen just sealer wrong header tank needs a plastic 1 cant find 1 atm only a guy on ebay i brought engine off with turnt out to be knocking so sent it back