This is often a cracked head gasket between oil passage and a cylinder.
8 spark plugs
There are four spark plugs on each side of your 1991 Chevrolet engine. The spark plugs will be near the bottom of the engine.
Every gas burning internal combustion engine has spark plugs. Diesel engines do not. Your Impala is not a diesel, so it has plugs.
No spark from coil, bad plug wires, or bad plugs.
3 of the plugs are on top of the mottor and 3 of them are on the bottom side
Remove the spark plug wires from your 1993 Chevy Astro spark plugs. Remove the spark plugs with a 5/8 deep well socket, by turning the socket to the left. Reverse the process to install the new spark plugs.
You can begin by removing the spark plug wires from your 1985 Chevrolet S 10 Blazer spark plugs. Use a 5/8 deep well socket to turn the spark plugs out. Turning the socket to the left will loosen the spark plugs. Reverse the process to install the new spark plugs.
A 2004 Chevrolet Trailblazer that has a 4.2 liter engine will have a spark plug gap of .044 inches. The best spark plugs for this vehicle are iridium spark plugs.
10
.035
the sparkplug gap on an 04 chevy optra is 0.032 Jeff
you rotate the engine to get to the rear plugs but the front ones are easy to replace