Smoky exhaust

[nickd01]

The car:
Chim 4.5 1999 with 45k on clock. Weekend only car, but used most weekends. No running issues aside from minor oil leak from sump; due to be fixed this week.

I noticed on startup this weekend that even after a slow-ish 10 minute crawl through London traffic that when I parked up the exhaust was billowing out a fair amount of smoke. Not "clear" condensation type smoke, but I think it was a white-ish smoke - it certainly smelt! Engine temp was around 50-60 I think. Another 15 mins later in traffic and I couldn't see it any more.

Should I be worried or ask my dealer to look at anything when I take it in?

[TVR keith]

Nick, have you got the right oil in it, does it use any, has it been changed recently?
Don't know whether your car gets a decent long run when you drive it, oil will need to be changed more frequently if shortish runs. In any event needs to be changed annually because of condensation in the engine.
If you are getting into very slow traffic before the engine is warmed up properly it could be that the mixture is rich which will produce smoke from the exhaust. The fact that its OK when hot seems to indicate that there is nothing seriously wrong. It might be worth getting the garage to check that the thermostat is operating OK, i.e. that the engine is able to achieve running temparature whithin the optimum time

Edited by TVR keith on Tuesday 3rd October 17:48

[nickd01]

Thanks Keith, I guess what normally happens is that I drive much further before stopping so probably never notice it smoking a bit initially.

It does use a bit of oil, maybe erm 1/2 litre in 4000 miles. Is that a lot? I've nothing to compare against.

I'll mention it to the garage, and just make sure the thermostat is fully open when needed. I actually think there might be an air-lock in the cooling system so I may just get it all flushed for winter.

[TVR keith]

Nick,
My 450 (42K miles)uses about 1/2 pint per 1000 miles, my mates 400 with 25k miles uses less. It definitely uses more when I drive it hard. Maybe the 450 is a bit more highly tuned or just because it puts out more power it will use a bit, don't know if this is normal. At any rate I shall not loose sleep over it

[chassis 33]

TVR keith said:

If you are getting into very slow traffic before the engine is warmed up properly it could be that the mixture is rich which will produce smoke from the exhaust. The fact that its OK when hot seems to indicate that there is nothing seriously wrong. It might be worth getting the garage to check that the thermostat is operating OK, i.e. that the engine is able to achieve running temparature whithin the optimum time

Also get them to check the coolant temp sensor for the ECU, if this is giving funny reading the ECU could be fooled into over fueling the engine.

Regards
Iain

[edward1]

May seem a daft suggestion, but check for PAS leaks. Mine used to leak from the U bend and drip onto the exhaust, after a while as the exhaust got hot it would smoke (whiteish), even when stationary the smoke would track along the exhaust and exit predominantly at the back. Once the leak was fixed problem gone no more smoke!