A puff of smoke

[Dalek]

one of my clients has just purchased a rather nice 2.2 which I hope to see join this group very soon.
One thing he has noticed is that although it runs really well it sometimes leaves a puff if smoke behind when he pulls away from a junction. He says it is quite rare but he has noticed it a couple of times. He also says that there seems to be a bit of black soot around the exhaust area on the rear bumper. Any ideas on what this could be?

 

[Lee]

Quite common with the M54 engines. This is likely to be one of two things. The CCV system (oil breather) or the piston rings are gummed up.

Depending how he uses the car there are a number of things he can do to try remedy the oil usage.

 

[spurs fan in a coupe]

Quite common with the M54 engines. This is likely to be one of two things. The CCV system (oil breather) or the piston rings are gummed up.

Depending how he uses the car there are a number of things he can do to try remedy the oil usage.

Yep, he could try putting a 2.8 lump in it, hooning round the Nurburgring for 10 laps and then a small puff of smoke once in a while is the least of his worries!

 

[Lee]

Yep, he could try putting a 2.8 lump in it, hooning round the Nurburgring for 10 laps and then a small puff of smoke once in a while is the least of his worries!

Blow up the 2.8 that didn't use any oil and fit a 3,0 that uses oil more than anything i've owned

I'm that guy!

 

[Dino D]

Blow up the 2.8 that didn't use any oil and fit a 3,0 that uses oil more than anything i've owned

I'm that guy!

Coming from an ex TVR owner that is worrying!

 

[Dino D]

My M54 330i drank oil from ‘new’ at 50k miles - I think it was the lowest mileage car I’ve ever owned but used the the most oil!
A good regular thrashing (not exceeding the rev limiter though ) helped but it always needed oil from time to time.

I never slowed down enough to notice any smoke though...

 

[Jack Ratt]

My black zed used 3 litres of oil travelling from Truro to Bristol to have it;s replacement engine fitted

 

[Mario]

Are you sure the puffs of smoke coming out junctions are not the tyres suffering from excessive acceleration? @Dino D @Lee I am surprised you didn't mention this as the most probable cause ;p

 

[the Nefyn cat]

My 2.2 has always guzzled oil, did the CCVV, no change, did the valve guide oil seals, made a slight difference. Next step would be pistons out and check the rings, but not sure if I can be ar5ed.

 

[t-tony]

They say it can be medicinal?

Tony.

 

[colb]

Was told by a Geman mate whilst travelling in Germany when the BMW in front of us puffed smoke now and then that it was common and due to valve guide wear. A change of seals may help but new guides would probably be the way to go.

 

[Lee]

I can confirm when I stripped my 2.2 engine down it was clear the rings were gummed up. Look at the oil deposits on top on the piston.

I removed the oil ring to find it blocked with crud. Good way to sort this would be use the 2.8 Oil rings, the newer M54 design is poor.

 

[Dalek]

Quite common with the M54 engines. This is likely to be one of two things. The CCV system (oil breather) or the piston rings are gummed up.

Depending how he uses the car there are a number of things he can do to try remedy the oil usage.

It is a daily driver, so what do you suggest?

 

[Lee]

It is a daily driver, so what do you suggest?

Starting cheap like suggested above I would replace the CCV (crank case ventilation) it's a like diaphragm valve that separates the vacuum and oil vapour this sits just under the manifold. When these fail oil vapour enters the manifold and gets burnt off.

If the oil/puffing still persists we've had good results with some engine cleaning products 'Sea Foam'

The problem I had with my 2.2 was, it was being used as a daily for only a 2 mile journey so the engine kept building up condensation (milky oil cap) and the problem kept coming back. When I used it for longer journeys the oil usage really dropped.

From experience I've never totally stopped the oil usage issues only reduced the consumption.

 

[the Nefyn cat]

I've read about this Sea Foam stuff, never actually come across it, let alone used it but may yet give it a try. Got to be cheaper than engine out and full strip. That sort of thing can turn into an endless job, just where do you stop? When I changed the valve guide oil seals there didn't seem to be an excessive amount of play, but did it with the head on so didn't get to check it properly, the seals were absolutely bu88ered, guess they were made of the same rubber they used for the Vanos seals and cam-cover gaskets.