dugsud

I have an 83 SC with 115K, runs superb, never any smoke when warmed up, not even when thrashed.
Uses very little oil (about 1L in 2K) and is good on fuel.
I am just curious as to why it puffs a bit of smoke when started from stone cold, after standing for a week or so. Not every time ether, it can stand for 3 weeks sometimes & is smoke free!
I was told this is normal for these engines & it helps if you allow the car to idle for a few minutes before turning it off.

Any comments?

joey c

i was told normal..could be condensation..whats the color..there are many threads on this subject,but it is normal.

dependencies

Your cylinders are laying horizontally for one thing, and any residual oil leaking past pistons and valves collects their when engine stands for a bit,

and on start up, hey-presto its first to get burnt.

If it bothers you, as it does me,
try parking on up-hill, or
down-hill slope if possible, as this seems to help mine a little

Modena 1

Does this mean that if there was a car that had been sitting for say...2 years, only getting moved around a lot (gas station) to get out of the way, but never fully warming up that it would smoke a significant amount for a long time? Trying to evaluate a car I'm looking at with a friend and stumbled across this thread.

Driver8

Modena

A car sitting for a long period of time will smoke more and for a longer time then the usual puff of smoke from a car started regularly. But the smoke should stop after a couple of min. If it continues then there is a larger problem. I recommend starting it and letting run as you look the rest of the car over and note how long it takes the car to stop smoking. If there is any real interest in this car a PPI is defiantly in order.

Cowhorn

Isn't the rule of thumb: white smoke on start-up=condensation/water burning off=normal; blue smoke on start-up=oil=can be normal if for a short period of time and small amount; extended period of blue or black smoke=significant problem that needs attention soon. At least in a nut shell that is what I recall from a recent post to a similar question. Double check me, guys.

Bob Westmoreland

Yes, it is normal. I have seen the sometimes smoke and sometimes no smoke on many occasions in cars with engines that have very little milage. If you want to read more on this I recommend Bruce Andersons articles in Excellence and Panorama over the past 40 years. He seems to be re-visiting this question every year or two. Another source is Up-fixin which is a compelation of do it yourself articles.

Crivens

White car chuffing like ivor the engine about 1 min into startup,
fairly normal probably condensation from the pipes + oil + worn guides

dugsud

Thanks for all the reply's.....very re-assuring

It usually stops smoking after around 10-20 seconds and only
when it stands for a while.

Never ever smokes after the first start-up of the day.

I'll stop worring about it now

Cowhorn

By the way, dugsud, great avatar!

dependencies

does anyone know, the difference in starting the car;

1; leave throttle pedal alone, twist key hope for best.

2; blip throttle,& twist key at the same time

Was wondering, if introducing extra jet of fuel into bores, would help dispel
any oil laying about in piston cylinders

recordmanv

I may be wrong, but on a CIS 911 you NEVER give it gas on startup as this can make it too rich and cause a backfire (blow your airbox!) If it is "twist key hope for best", then you have an ignition/WUR problem. It should be "twist key with confidence, she'll start right up" Good luck.

Peter Zimmermann

depend: Nothing fuel related happens when you depress the throttle pedal on a CIS car that's not running. There are no carb-type accel pumps, etc., that deliver raw fuel to the intake ports. When you open the throttle on a CIS engine you disturb the factory calibrated air/fuel ratio by leaning out the engine. When the engine is cold the cold start injector supplies the exact amount of supplemental fuel that the engine needs to start, and it works along with the warm up regulator, which regulates fuel delivery to the injectors (by lowering control pressure so the sensor plate may lift the fuel distributor plunger further). The system is designed to be a "twist the key" to start, with no other driver input necessary. If the car doesn't start properly in all temperatures there is something wrong with the system. Now, back to the thread. Bob W. is correct, I've seen engines with perfect leakdown numbers do it, regardless of mileage. Yes, there can be a problem that is causing the symptom on a particular engine, but they are rare.
Pete

Dave Thomas

One way to reduce smoking on startup is to let the engine idle for 15 sec or so before you shut it off. This pumps oil out of the crankcase and fills the oil tank - you can watch the oil tank gauge go up. When I remember to do this I never have any startup smoke, if I don't I get the breif smoke you describe. Last summer, my car sat for 5 months while I worked on the suspension and brakes and I had ZERO smoke on startup.

dugsud

Thanks Dave,
That actually seems to work for my car too! I've only left it for a short time but it does make a difference.

Thanks everyone else for the input too.