Pinking??

Dear all readers.. I do hope you can shed some light on my problem below!!

After recieving a 1990 E30 320i from a family member, I have been experiencing running probs.

At around 2000rpm, in any gear, at any speed, the vehicle suffers from a very slight 'hesitation', I believe the technical term is called pinking??

I call it a 'hicup'. Like I say it is only around 2000rpm. Whether the engine is hot or cold..

I have had the engine electrical system and ECU checked but no fault found. Compression, Sparks + HT's, Injectors, Fuel Pressure, Air Flow, Timing, have also been checked out with no probs..

There is also a very rough idle, hot or cold, that sometimes stalls the engine randomley. I have had it checked, they say its related to the pinking... ?

I also suffer from high fuel consumption (260 miles from about 50L of unleaded) (is that bad?? I've never owned a BMW before, so cant compare) Again they put this down to the Pinking.. ?

The vehicle has only done a genuine 55k in its time with a full BMW history.

Has anyone got any ideas?? please, I love the car and would love to get it back to its mechanical glory!!

Help is needed!!

James. 

 

 

I used to have a '85 323i it had similar probs as you describe, rough idle, slight loss of power, rough acceleration etc, it was a Mercedes mechanic who soughted it out! He recommended �STP Inlet Valve Cleaner�, it used to come in a yellow bottle. I never seem to see it in the shops any more, but did manage to order some through a local store last time I needed it. Never thought much of petrol additives until I used this stuff. 1/2 a tank later my car was running great, acceleration was smooth I was happy.

As far as economy goes 260miles/50L = approx 24mpg, depends how you drive it, I would have thought it should be better, my 323i used to achieve approx 29 mpg. My E30 318is gets 37mpg, lovely!

As Kevin's link above says 'pinking' is pre-ignition, the car will sound like a bucket full of nails on acceleration, especially under load and up hills.

P.s Try running the car on a good premium fuel for a while and see if this helps, and I don't mean Tesco! Try Shell Optimax, tiz expensive, but it may sought your problems.

Mark

My 325i had a similar problem a while ago, it was only around 2500rpm.  After replacing everything i found it was the fuel pump relay.  I'd take your relays out and clean them both, should be a fuel pump and a DME relay might be either, about �8 off my local dealer.

what petrol do you use? Try a few tanks of Optimax!