1994 BMW E36 M3 - White smoke (over fuelling?)

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Thu 20 May 2010 21:05
1994 BMW E36 M3 - White smoke (over fuelling?) - mlambert

Hey guys,

Right my car starts fine and seems to idle and run ok until she starts warming up (roughly around the end of the red bar), when she seems a little down on power but also starts smoking from the exhaust. Upon parking up, she spits out plenty of smoke and even some petrol splashes and reeks of fuel.

I've got a peake research tool and she's showing no error codes logged, the MAF is only a few months old, she runs on oldish NKG plugs (she doesn't like bosch).

The other thing of note is I had a tiny rad leak a few weeks back and at the advice of a local RAC bloke on his break, I used rad weld.

Does anyone have any ideas? If it's an air leak in a pipe, wouldn't that trigger a code? I've been told the rad weld could have caused problems with my coolant temperature sensor (and even damaged the heads), but the car has never overheated and I'm pretty sure the smoke isn't steam.

Thanks,

Marc.

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Thu 20 May 2010 22:33
1994 BMW E36 M3 - White smoke (over fuelling?) - Chris_944

White smoke is usually the head gasket in my experience.

You got any mayo under the oil cap or are you using water? might be worth doing a compression test if youhave the kit.

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Fri 21 May 2010 17:37
1994 BMW E36 M3 - White smoke (over fuelling?) - mlambert

I've had the car looked at by a mechanic and have her booked in for an emissions test tomorrow. He reckons it's not the head/gaskets too, which is a relief.

What he did say though was it had too much water/coolant (and radweld ::) ) and that the main fan had play in. I will replace the water pump.

I'll post the emissions results to see what light they shed.

Cheers,

Marc.

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Sat 22 May 2010 12:58
1994 BMW E36 M3 - White smoke (over fuelling?) - mlambert

Hello again,

Right a quick summary: '94 M3 pouring out whitish smoke from the exhaust when hot, car slightly down on power. No ecu codes and to top it all off, even though the car filled the mechanics garage with smoke, the emissions test was spot on.

As far as I can see the car isn't loosing coolant for it to be steam, but from startup when cold (all the way through to warm) she stinks of fuel. The guy reckons it must be from the exhaust (it's a 2nd hand evo exhaust fitted 6 months ago), but there's no obvious leaks or failures in it. He said he'd do a compression test, but he doesn't think it's a head gasket: i.e he doesn't have a clue what the smoke is and where it's coming from. The main fan has a little play so I will change the water pump, but as far as we can see it is working ok.

So I've got no ecu codes, no problem with emissions, no coolant loss - plenty of smoke.


So help please people, through any idea my way!


Marc.

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