If a lifter is pumped up and can't or doesn't bleed down, it would not allow the valve to fully seat. Measuring valve stem height would confirm that possibility. If the valve face, or seat, is burned, valve stem height would be within specs, but carbon could still build up. It could be something as simple as a piece of carbon got stuck between the face and the seat. Carbon build up is common in the EGR valve, could be a piece made its way to the valve. Rings are not a common problem with 4.3's unless they've been neglected on the oil changes. Also, if it were a ring, the engine would most likely smoke out the tail pipe.

 

Okay, I see what you're saying about the rings. So, it's either a bad valve or lifter. I didn't think I could be the push rod simply because this is not a race engine nor do I neglect my oil changes

Well, we'll measure the valve stem height before we take the head off. Is there a way to verify a bad lifter with the head still in place? Wouldn't simply pushing down on the rod confirm this idea?

 

If a lifter is pumped up, and the valve spring can't compress it, you won't be able to compress it either! If that's the case, you can disassemble the lifters, (one at a time) and clean them out, you don't necessarily need to replace them unless they're damaged. You don't need to remove the cylinder head to remove lifters.
Measuring assembled valve spring height will tell if the valve is fully closed. If the height is less than spec, it could be a pumped up lifter or carbon stuck between the valve face an seat holding the valve open.

 

I think the ECM is bad in my 1995 chevy blazer...So when buying a new one will it be required to get flashed?

Thanks -pblaze-

 

To avoid confusion, it's best to start a new thread here:
https://blazerforum.com/forum/newthr...newthread&f=41

 

Change your fuel filter and the problem will go away. Service engine will go off too.