Intermittent oil smoke

wdfifteen · wdfifteen's Garage

I am perplexed about the blue smoke coming from the exhaust of my '88 Carrera with 71,000 miles on the clock. I've read many posts here about blue smoke from the exhaust and I cannot figure out what is going on with my car. Sometimes it will smoke like a steam engine until it's warmed up, sometimes there isn't much smoke at all. This morning it had been sitting for 6 weeks and I was so expecting a blue fog that I pushed it out of the garage before starting it. Nothing. Just a puff. I loses about a quart in 1000 miles (with no puddles in the garage) even when that 1000 miles includes two track weekends. But some mornings at the track it smokes so much it's embarrassing. One pit worker even warned me to keep an eye on my oil level. I can't find any rhyme or pattern to when it does or doesn't smoke. Any suggestions??

germanfan · germanfan's Garage

could be valve guides

haggis780 · haggis780's Garage

Any chance you are fouling a plug on start up?

wdfifteen · wdfifteen's Garage

I forgot to include that a leakdown test showed the 2-3% across the board. If the problem wasn't intermittent I would conclude that the problem is valve guides, but wouldn't that be consistent? I keep thinking it is one or two guides that are loose and it smokes like crazy if those are left open (or closed?) on shut down. I dunno.

dkirk · dkirk's Garage

wdfifteen,

I experienced the exact same symptoms from my '88 Carrera. Doing a top-end overhaul is the fix. Your engine needs new valve guides and stem seals. The link below describes my experience:

3.2 Top End Overhaul – A Success Story

I put around 3000 miles on my car after doing this rebuild and just the performance increase is worth the effort. And, not a hint of any blue exhaust smoke.

wdfifteen · wdfifteen's Garage

Wow! Thank you for the link and the encouragement. I've been afraid this procedure is in my future and you've pretty well confirmed it. My home shop isn't heated in the winter and my "real" shop is full, so it will have to wait for warmer weather. Fortunately I don't have to do the clutch, but I do intend to do the oil seal routine, replace the fuel lines, and get rid of the AC compressor.