Volvo 850 rough running, terrible MPG

[stevesuk]

Hi guys,

Trying to help out my sister-in-law who is running a 1994 Volvo 850. Its the normally aspirated engine (2.4 I think), on approx 120k miles.

Its been running fine up until recently, when they had issues with it stalling and then not starting. This was solved by changing the fuel pump relay (a common issue I understand).

But now it has a second problem. It runs OK, and idles OK. But when you pull away it generally runs rough, uses a lot of fuel and stalls.

Taken it to a local garage and they wouldn't comit to what is wrong, only saying that they could change the spark-plugs, HT leads, distributor cap etc. and it "might" improve it.

I thought maybe the new fuel pump relay could have been a faulty part, but she says it was running rough before they replaced it.

Anyone have any idea what it might be, and whether anyone knows of an indy Volvo specialist somewhere in the Poole, Dorset area we might try?

It seems a shame to scrap the car, because it has no rust and seems sturdy. But because it was a cheap car, she doesn't want to spend a fortune mending it either.

Any help appreciated!

Thanks,

Steve.

[Rockatansky]

Sorry, I don't have any suggestions for you - but if it's not too far to travel, Russ @ RT Mechanics in Surrey has a very good reputation in Volvo circles.

http://www.rtmechanics.co.uk/

[stevesuk]

Thanks anyway, but I'm not sure the car would make it to Surrey in its current state

[walter leever]

question;when she or you accelerate does it smoke(black)and do you feel a hesitation?

If so look at the airmassmeter(prob.kaputt)

gr,walter

[stevesuk]

Thanks for the reply. Can't say I've noticed it smoking, but she tells me it has been using a lot of oil.

From what I've witnessed, it just sounds rough, almost like its not running on all its cylanders. She also tells me its using £20 of petrol every day (and its not like they do a 200 mile round trip to work or anything daft like that).

Will check out the sensor.

Cheers,

Steve.

[morgrp]

Is the breather and flame trap blocked up? common on 850's that have been on crap oil - not sure it would make it run that bad though

Edit - Also is the Lambda Sond light on the dash? upside down green Y in an orange light - could be a cam sensor gone or Lambda sensor in the exhaust. They have been known to drop injectors too which results in high fuel consumption, lack of power and poor running - if this is the case, they tend to chuck fuel down the exhaust system making it red hot so be careful.

Edited by morgrp on Friday 10th July 12:27

Edited by morgrp on Friday 10th July 12:28

[g32turbo]

Sorry with the late reply, only just noticed the thread. The symptoms sound the same as with my wifes 850. Turned out to be one of the HT leads shorting out against the head. Pull each HT lead off the plugs and look around the insulated extension for any signs of the insulation breaking down.