1999 GP 3800sc into 1986 gt. car will start and run well, BUT, I have to "crank it" about 6 times before it will fire up. > As soon as the battery is connected, the fuel pump is" running non stop" ( Key not even on). you can hear the fuel flowing through the lines . once the car starts, it runs fine. shut off the key and the fuel pump still keeps running till the battery is disconnected ! WHY ??? I have 3 -3800sc conversions, and this car is the only one with "this problem". Any ideas ?
I would check the Fuel Pump relay to see if the contacts are stuck in the closed position. Easy to swap in another relay. If it's not that, then most likely a miswire in the harness. As for hard start, might be the engine is getting flooded because of the fuel pump issue. If that doesn't clear it up, don't know....
well back to square 1 ! the reason it "stopped working" was the 203 PLUG was" loose". SO..... now the pump runs WITHOUT the key on (whenever the battery is connected). The Only way to "shut off" the pump is to pull the plug on the" oil sender unit" ! BUT the pump will not come on, no way, if you turn the key on, unless the oil sender is plugged in, and then it won't shut off !
Could it be a bad oil pressure sender? Sounds like it's stuck in the energized position keeping the fuel pump running. Or it's not dissipating the oil pressure (or what it thinks is oil pressure) due to a clogged or partially clogged port in the sender.
Does your oil pressure gauge respond in-step with varying throttle positions or is it sluggish? If sluggish this could indicate a port blockage in the sender. Stuck contacts in the sender will give same results as above. Swap out the sender from one of your other conversions and try it.
Just my 2 cents...
Spoon
------------------ "Kilgore Trout once wrote a short story which was a dialogue between two pieces of yeast. They were discussing the possible purposes of life as they ate sugar and suffocated in their own excrement. Because of their limited intelligence, they never came close to guessing that they were making champagne." - Kurt Vonnegut
Now, I've discovered that the IAC is also "Powered" with the Key OFF ! I really hope I don't have to pull the engine to pull the harness to check every wire ! is there any way the ign switch or "something else" can cause this ?
Shouldn't have to pull engine to check harness. For starters pull connectors from ECM and IAC and use a multimeter to check continuity pin to pin. If 1 pin is not in the right hole that means there are 2 errors and so on. Have a good magnifying glass and plenty of light.
Spoon
------------------ "Kilgore Trout once wrote a short story which was a dialogue between two pieces of yeast. They were discussing the possible purposes of life as they ate sugar and suffocated in their own excrement. Because of their limited intelligence, they never came close to guessing that they were making champagne." - Kurt Vonnegut
If there is a short or open connection somewhere here is the easiest way to find it. Disconnect positive battery terminal . Now put a test lamp between the + battery terminal and the battery cable terminal. If the light is on it indicates that a circuit is energized. Now go to your fuse box and pull out each fuse one at a time and watch the light. If the light goes out ,that circuit is energized and it then must be decided if it should be or if that is a drain from a short. Getting back to why your fuel pump won't energize; wrong relay, broken connection or bad relay as Joe has suggested.
------------------ " THE BLACK PARALYZER" -87GT 3800SC Series III engine, custom ZZP /Frozen Boost Intercooler setup, 3.4" Pulley, Northstar TB, LS1 MAF, 3" Spintech/Hedman Exhaust, P-log Manifold, Autolite 104's, MSD wires, Custom CAI, 4T65eHD w. custom axles, Champion Radiator, S10 Brake Booster, HP Tuners VCM Suite. "THE COLUSSUS" 87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H " ON THE LOOSE WITHOUT THE JUICE "
at the relay, Tried 4 different relays, no difference. there are 2 wires HOT going INTO the relay. ORANGE/BLACK,, and another one. I will check with a light and the fuse box. the ONLY wire that is HOT with the Key OFF is the" oil sender", I was Mistaken about the IAC,(the key Was On). have not checked with the Light yet.
