Thread: Engine won't start or idles rough at above 180 degrees after its been shut off.

I own a 2000 Grand Prix GT Coupe with the stand 3.8 liter V6. Lately this has been happening I can drive the car as far and as fast as I like with no problems, this past summer I had the dreaded dex-cool leak and had to pull the whole top end off while we were there we cleaned up the intake and tb and put in some new iridium plugs as well as some new wires. So the engine itself is sound that part I am sure aside from a small leak around the oil pressure sending unit. So the issue I am currently having is that even though I can drive it as far as I want if the engine is over 180 degrees when I go to start it like if I go to a shop for a while or if I head to a class on a really hot day. I won't get any fuel to the engine, it has even more trouble running if the car is parked uphill. I know my battery didn't pass the test for the proper amount of cranking amps and that I will need a new one. Is it possible that this is the issue or is the fact that my sound system is grounded in the trunk by the fuel pump the real issue. I already know I need a bigger alternator since it can't keep up with my 1800 watt's rms but I'm trying to figure the fuel pump issue out first before I go any further.

Well my battery didn't pass the test at its recent checkup so I'm pretty sure thats the issue but since I don't have the funds to pick up a battery until next friday im trying to make sure that its the problem or atleast get some other opinions. As for confirming the fuel pump issue, I could tell based upon the idle loping to be sure on one of the times it wouldn't start (the engine was over 180 degrees and i was dropping off a package at the post office) when i tried to start it the second time I used a screw driver to press down the valve on the fuel line ontop of the engine and nothing came out. So I bought a fuel pressure checking tool that I can place on the pressure valve above the motor and I'm getting less on startup than I should. If I rev the engine to a higher RPM the alternator turns over and can provide more power also the fuel pump tries to provide more fuel. It seems like my battery just doesn't have enough power to get the fuel pump over the initial hump caused by the higher pressure in the hot fuel lines but when the engine bay has cooled down it can get enough to start up the motor.

I'd fix that oil leak asap. It can turn into a big leak very fast if it's leaking from the oil pressure sending unit. You can lose oil pressure real fast. It's a pretty cheap fix and can save your engine.