I just bought a 95 z28 project car. The body and interior are in good shape but the engine is running rough. When I first bought it you had to crank it forever and hold the gas down to start it. It would act like it wasn’t getting gas or spark then it would pop and backfire. After you get it started it has a noticeable miss but will start pretty easy when you shut it off. It is blowing oil out of the dipstick and if you take the fill cap off you can feel pulsing pressure. I thought it might be a head gasket but it doesn’t burn antifreeze and I think the only oil it uses is from the dipstick. It doesn’t smoke. It runs and drives but way underpowered. The previous owner had the following parts replaced: opti, water pump, fuel pump, plugs and wires. All after it started running rough.
Any ideas?

 

seems like it has blow-by which is prolly making compression drop, might wanna start with a compression test to see where you stand

 

That is my plan for this weekend. I am not excited about trying to get to all of the plugs. I have never been able to see most of them. I am thinking about a full rebuild any way. Just pulling the whole motor, but I have never done that in a 4th gen either.

 

ya its no fun at all, but its soundin like it may be the only option