Hi. Not had my rs turbo long. Anyway decided to change the oil and filter. Refilled oil as ive done a million times. Started the car up and it sounds like a subaru! Very very badly misfiring. It ran fine b4 i changed the oil. Ive checked the injectors and they are spraying fuel. The fuel pump primes. The plug leads are new magnacor jobbies. The plugs are very black and sooty though and there a month old. Please help someone. Cant understand how changing the oil caused the cars poor running. Im on mfi engine.

 

Also meant to add, it wont even idle, just cuts out too.

 

Is the dipstick and oil cap correctly fitted, sounds like air leak providing your car is still on mfi with standard breather.

 

What Stu has said, if not then it's probably just coincidence and you may have disturbed something whilst doing the oil change that has then failed.

 

I had a poke about this morning and it wont even start now. The plugs are black and wet. I cleaned them up and checked the gap and still no joy. Ive flattened the battery now. Checked oil cap and dipstick and there sound. It ran perfect on friday and on saturday after an oil change not running? When it started yesterday it was chucking black smoke out the exhaust. The oil stunk of petrol that i removed. Could the previous owner added something to the oil to mask a problem as it was thick and a glue like consistency?

 

could you do a compression test .........

 

Think thats my next plan. Try a compression test and see what i find. Got a bad feeling theres something gone wrong inside the engine. It doesnt even start up now, just turns over and over and reeks of fuel. What other things could it possibly be? Know its hard to diagnose on a forum. Does anyone know anywhere in leicestershire that could take a look at it? Struggling with it not starting though.

 

sounds like it isn't sparking, have you got spark on all four plugs? coil ok?? Although does sounds like the previous owner may have used some sort of treatments to hide an issue.

 

All 4 plugs are sparking well. Its got a group a coil and new coil wiring. I fitted that meself and have checked all connections and there all good. As i said earlier, so weird how an oil change has basically destroyed the running of the engine. Makes no logical sense to me? When it actually fired up yesterday the whole engine was shaking so badly in the engine bay.

 

Can you remove the breather pipe from the metering unit and block the port on metering unit and see if it starts? From what I remember this will rule out air leak? Karl from fpt may confirm.

 

I will try that then tomorrow. Hope its something easy and not a compression problem. Seriously cant afford to rebuild the engine.

 

have you disturbed the thermo time switch? it sounds as if its overfuelling massively. that yellow sensor at the back (in the vicinity of the oil filter) can cause problems if its damaged or the wiring is damaged

 

Have a check of the heavy plastic pipe that runs from the engine to the metering unit. This gets brittle with time and one cracked or holed can cause all sorts of issues.

 

Had a good look under the car this afternoon and noticed the thermo switch plug was just hanging. Plugged it back in and its running spot on again. Must have knocked it off when i stuck my hand down to remove the oil filter! So chuffed its working again. On the plus side a company called street racers in syston are able to set up mfi engines for anyone in leicestershire. Thanks all for your advice. Steve.

 

Nice one, glad you've got sorted.

 

Well done that man!

 

Ah always nice when it's an easy fix!