Originally Posted by Mark rsa2au
The black Smoke is fuel, can smell it and see it on the water. New TPS ordered, and reconditioned injectors installed. Idle controll valve faulty and also on order. Replaced Maf sensor already. ECT seems fine but did not check exact resistance vs temp, but it did change with temp, will also check that.
Heading out to the boat tomorrow to replace parts, will check readings voltage etc before and after.
How did you determine the parts being faulty? If you tested them, fine, but if you just started replacing parts in hopes of finding the solution, it's going to be an expensive, frustrating journey. Buy a manual- it has testing procedures for the various systems, each in their own section. If you know someone who has serviced GM engines, ask them for their help.
Did you check fuel pressure, yet? What's the voltage when it's running? These need to be at the correct voltage in order to operate properly.