Now what: same problems after rebuild

[libbybapa]

Air in the fuel line causes smoke. Also, if the "occasional" bubble is from the vane pump having to suck harder than it should (clogged filter or pump screen) then the residual pressure in the pump will be incorrect. The residual pump pressure is what controls the timing advance. If it is not correct your injection timing will be thrown off as well also causing smoke. No bubbles are allowed, hard sucking isn't allowed either.

Andrew

[dchardy]

Thanks for the info, I didn't know fuel line vaccuum was involved with timing...I checked my clear fuel line, and there are no bubbles, so I think I'm ok, though I may put a vacuum gauge on it just to be sure.

After a few more test starts/drives, it seems that engine temperature is the main factor in how it's running - quite a bit of blue smoke upon start, but idles OK,not much smoke, but when I increase rpms slowly, at about 1800 it seems to miss/sputter and that's when I see quite a bit of blue smoke. After the engine gets hot(~10 min), it doesn't do this - runs great, actually. Interestingly, I ran it about 5 minutes, smoked of acceleration, then let it sit for about 10 min.Came back, started it, didn't smoke on acceleration. Could be a fluke, but seemed odd.

But all in all, I'm psyched - the thing is a blast to drive.

[vixentd]

Did your vw ever stop smoking? What was the problem?

[dchardy]

you know, it never really did. It only smokes for about 30-60 seconds, more on cold mornings. After it warms up a bit, it runs fine,no smoke. So I decided to just drive it and not worry.

I think if the smoke *doesn't* go away when it warms up, then there are problems that should be addressed. But after reading a lot of posts on the subject, it just seems the consensus is that a bit of smoke when cold could be considered normal.

-David