Originally Posted by Mark rsa2au
Not big on waiting... have started testing.
Battery Voltage engine off - 12.7v. Engine on tested 13.5v ( I think) last week.
Grey Wire to earth 5V,
Resistance to earth: 0.73
resistance across Blue to White pins on actual TPS Idle=2.16, WOT=6.19
Gray wire 5V
Resistance to earth 0.73
resistance from Black pin to Green pin 5.44
JimN: Read from other posts that manual is available and will order. Freight is more than book costs and 2 to 3 weeks wait.
I have heard of that mythical creature who knows how to maintain a GM V8 motor and who is not scared of it being in a boat... jokes aside yes I know a mechanic who will do it but again 2 to 3 weeks wait and expect huge $$$$. supply and demand
Rigged a tyre pressure guage to test fuel pressure, 25psi at idle but was leaking a little and I did not want too much fuel floating arround...... so I stopped.
How did you test the sensors? DON'T pierce the insulation on the wire. Use a stick pin and slide it into the green seal until it makes contact with the terminal, then test.
What is the idle speed of the engine? If the IAC is always closed, the RPM should be low, or it may not even idle at all. It definitely shouldn't idle well and may need the throttle to be opened just to keep it running. This may be the only real problem, although the fuel pressure is a bit low. Check the fuel filter and make sure it's clean. Your pressure should be in the 30 pound range at idle- the factory-recommended tests for fuel pressure are: Key ON/engine OFF, idle, 2000 RPM and WOT. Make notes of all test results and keep them as a baseline. Once it's running well, do all of the tests again, so you have something to compare to.
Use a fuel pressure gauge- these have a purge valve and you pcan use that to not only purge the air from the line, you can take a fuel sample (which I strongly recommend). If you know any auto mechanics, they should have one. Ply them with beer, if you have to.