Pro

When I first bought this car (3 months, or so, ago), I used to just start it up and go (it would turn over for a second or two, and then have a white smokeout for a while). Someone mentioned that the seals were leaking oil into the combustion chambers.

Well, I have noticed recently that if I just turn the key and let it sit for a few seconds, and then start it up, it fires up perfect (starts immediately) and no smoke whatsoever.

If I had a seal problem, then why would it not smoke up when I just let the fuel pump prime a couple extra seconds before startup?

BTW a video of it smoking is on my website. Might take a few minutes to download for you (capped cable uploads at 256kbps).

Blownyellow

Have you tried "just starting it up and going" since you developed your new technique of building more fuel pressure?
I am curious if it will smoke the next time you don't prime the system.

Martin

Rice Killer87

white smoke is coolant,not oil. burning oil is blue smoke

Pro

Download the video and judge for yourself.

Martin, I dont understand your question.
If I wait for 5 seconds or so after turning the key (first startup), no smoke. If I just turn the key and start it up, plenty of smoke (and hesitation).

Later on down the road, if I have to turn the car off - I can just turn the key and start it up... no smoke, no hesitation, nothing.

kraftopia02

i watched the vid...looks very blue to mean, but it's hard to tell becuase the shadow of the car....

but it (again...lots of peeps posted this prob) sounds like a small oil prob that is simply invisible when the engine gets to operating temp.

Does your engine use oil at all?

StealthElephant

Wait, it only smokes on the first startup after sitting a long time, or if you let the fuel pump work it wont' smoke no matter how long it sits?

That makes no sense, the fuel pump should have no effect, neither should having the key in.

My 305 had leaky valve seals, the 1st start up of the day smoked, none after (since oil hadn't had enough time to collect in the cc)

Pro

Sounds weird, yes, but I have tried this over and over for the past few months, and I get the same results every time. I will take videos when I can.

Situation 1:
Turn key and start (with no delay). Car turns over for 2 or 3 seconds. Car starts. Car stumbles a little and puffs of smoke come out immediately. Motor has trouble keeping constant RPM (varies from 600-1000).

Situation 2:
Turn key and wait for several seconds. Start vehicle. Car starts up very quickly with no smoke. RPMS have a little bit of a problem staying constant, but not as bad as sitch 1.

(Once car is warmed up, no problems whatsoever...)

DrDUKE

You know, my car is doing the same thing.

I just figured it out myself a few days ago. Sometimes in the morning i would start it and get a blue smoke. I figured no problem 117000 miles, but it didnt loose any ( noticable ) oil between changes. The thing was it only smoked some times. I found that turning the key to the on position and waiting for the fuel pump and things to come on made the car start better and with out smoke.

I cant figure out why this would be, its silly really.

I have a TPI 350 btw
edtit: in fact it is a 1991 Z28 too, identical car as yours.

Blownyellow

I wonder if it has something to do with the afterstart enrichment program on your guys' cars.

Maybe when you don't let the fuel system get up to pressure before starting, the engine sees it as the injectors not supplying enough fuel and dumps it in during the cranking sequence.

It's kind of like fludding out a vehicle by "bumping" the ignition momentarily with out allowing the vehicle to start. I would also say that the problem is probably compounded by a leaking fuel system that bleeds off all pressure in the lines after an extended period an thus the car doesn't reach full pressure when the key is turned on.

If all pressure is out of the system, it will not gain much more than half the proper PSI level from just cycling the pump once, this is probably why it still runs a little rough even if you leave the key on before starting.

Just an idea, it may or may not help you out.

Martin

aklim

Could the injectors be getting clogged so it needs the extra pressure to spray the fuel? My car when stock started up on the coldest day with barely more than a twitch on the key. When it is warm, it takes a bit more.