I have posted past threads on my 88 iroc and stalling and idling issues. Well after today I replaced the maf, relays, Tps, and Iac which all checked out with voltage and Iac and Tps was reset. Well to all avail my frien and I rechecked again all the vaccum lines and ignition firing order all is the same as it was before this situation arrised. Well heres my question on the rear of the drivers side valve cover is a metal tab which looks to me as a possible ground hor a wiring harness which I only noticed till now. I rechecked my chiltons and according to it this on a 1988 5.7 is the ecm ground harness uh-oh. Well I want to know if this is correct or what this grounds because it seems to me that if the ecm is not grounded then it is not seeing the sensor output and I believe would be blind and maybe cause this engine to fall flat like it does thanx Tim

 

There is not a grounding point on the valve covers, however there is a grounding point on the rear of each cylinder head and is located just below the valve covers.

 

That's what I was thinking. It goes from the back of the cylinder head and grounds to the firewall I think.

 

There is one on the passenger side that is a braided grounding strap that goes to the firewall. All the others and there are about five or six are either grounds for the ECM or other components.