When I start up my truck when it's cold it smokes pretty good for a couple of minutes. However, if it is a warm day it doesn't smoke at all. When I changed my plugs/wires/cap/rotor last week two of the 8 plugs had oil residue on them. They weren't soaked/wet but you could sure smell it and they were black not the faint brown they should be.

Could this be valve seals or some other problem?

Truck is a 1990 4x4 with 5.8L engine.

Thanks

 

yep sounds like the valve seal to me if its only for a couple minutes at start up!!

 

How long is a couple minutes? Are you sure its not just Condensation? All vehicles have water vapor smoke when its cold.

 

Depending on the weather it smokes heavily for 2-5 minutes. I was hoping it was just condensation but the huge plume of smoke pouring out the exhaust when I'm driving down the road makes me think otherwise.

 

I had a truck once that had bad valve steem seals. I put in a can of risoline and it really helped. Didn't stop it but then, i wasn't smoking out the neighborhood anymore either.

 

If its white smoke, its water. If its black then I would probably believe its bad valve seals. However, the fact that you only see it on cold days makes me believe it is Condensation.