Hi there,

I've owned my dohc 8v Sierra for a while and it was never an overly smokey car. Now I haven't properly drove the car in 4-5months but I just let it sit and idle in the drive. I was working away from home a little while back and I hadn't started the car for about 1 month and when I did it was very knocky like a ticking sound that lasted about half an hour before it cleared. This has happened before and it went away fine. I always check the oil before starting and disconnect the coil to turn it over several times.

Now the ticking has went the car smokes a lot even when you just start it and let it run for 30 minutes it still smokes when revving. I took it out for some sideways last weekend and left a large plume of smoke.

So either valve guides or piston rings what do you think?