m3 e36evo - cylinder prob

[craigw]

Bit of advice please guys, I'm not very tecchie so dont know about this stuff.

A friend of mine has a 97 e36 M3 EVO and he uses a "BMW specialist", he has noticed performance lacking recently.

The specialist has said 2 of the cylinders are not producing at 100% and he's going to try to flush the engine to clear any possible blockage.

Does this sound right/feasible? I just want to check he's not being fed porky pies. Thanks guys.

[M3EVO]

VANOS!

[craigw]

and.... ? Sorry, I have heard of vanos & I know its very bad if it goes wrong but what do you mean mate ?>

[M3EVO]

BMW are the only people that should be commenting on this car. Not helpful I know, but above all, no specialist IMO is up to the task. Unfortunately this comes with big expense as I realised my local dealer charge £95 per hour plus VAT (Baron's).

If he gets the car on BMW diags he may find a cam timing fault or a VANOS fault on the list. It is the most common problem with this car. Some units last 10k, some 60k. Lucky dip really. The cast iron block is pretty bullet proof so I dont think that it is cylinder related at all. It would take a lot to shag a block as compared to the 328 nikasil probs. If it is VANOS, I think the only specialists that would touch it is someone like Hartlake 01634 294115

[craigw]

apparently his symptoms are that it seems to be slightly down on power all the time and turns over slowly when starting (although I doubt that's connected)

[craigw]

I think he had the vanos unit replaced under warranty last year.

[M3EVO]

I know this may sound weird, but get a straw and put it on the top of the inlet side of the VANOS unit a listen at the other end. If you hear a loud ticking at idle it is likely to be the unit. The Diags will confirm it at the dealer. On my car, it was the actual drive pinion and not the high pressure side of the unit. Basically, under a Technical Service Bulletin, the fixings (Allen Bolts) used to mount the unit to the head were supposed to be replaced on all E36 EVOS. Some went amiss and eventually snapped due to bad material hardening. This wears the drive gear and also coats the engine bay with oil. From the invoice I believe that the majority of the cost was labour due to the time needed to set the cams up again.

[craigw]

do the power symptoms sound like vanos?

[M3EVO]

Yes, The power loss symptoms would be similar to putting a low grade fuel in, or driving at an altitude. About 10% loss over the rev range and more fuel consumption. I think that the DME actually prevents any movement of the gear so no smooth overlap occurs (fuel consumption) and no advance or retard at any revs (low performance).

[craigw]

thanks, much appreciated.

[M3EVO]

craigw said:

I think he had the vanos unit replaced under warranty last year.

Like I mentioned, these can last 10k or 60k. Luck of the draw. One of the guys on the E36MPOWER group on Yahoo had 4 units on a 50000 mile on a 1997 M3 Conv.

[craigw]

he's now been told that 2 cylinders are blocked and the head have to come off. The guy said due to very low oil level lots of crap has got in. (This sounds like bo**ocks to me) Does this sound feasible?

>> Edited by craigw on Thursday 6th November 12:01