99 Silverado - Burning Oil, Smoking bad

I have a '99 Silverado (4x4, 350 Vortec, 165k miles) with a few problems. :banghead:


1) It's burning a lot of oil.

2) It's smoking really bad. It only smokes when you start it or gas it, but it's smoking white although it smells like burning oil if you are driving behind it. It also wasn't smoking as bad until the shop said to put a can of sea foam in the gas and oil. We decided to drain them both and put all new in, but it's still smoking bad.

3) The 5 and 6 cylinder keep missing. We have replaced the plugs twice but they end up getting corroded again. Coils are good.

4) It takes a few times to start it. Usually you have to turn the key on and off three or four times then try to start it. Usually the second time it will fire up and start smoking.


I was told it could be a valve guide? What do you guys think?

I have a '99 Silverado (4x4, 350 Vortec, 165k miles) with a few problems. :banghead:


1) It's burning a lot of oil.

2) It's smoking really bad. It only smokes when you start it or gas it, but it's smoking white although it smells like burning oil if you are driving behind it. It also wasn't smoking as bad until the shop said to put a can of sea foam in the gas and oil. We decided to drain them both and put all new in, but it's still smoking bad.

3) The 5 and 6 cylinder keep missing. We have replaced the plugs twice but they end up getting corroded again. Coils are good.

4) It takes a few times to start it. Usually you have to turn the key on and off three or four times then try to start it. Usually the second time it will fire up and start smoking.


I was told it could be a valve guide? What do you guys think?

what I think you got here is coolant is getting into the engine ...this is causing the corroding plugs..then the oil gets contaminated causing the egine wear to consume oil..

my guess you need a new engine..remove the valve covers first see how bad it looks..