SHE LIVES!
#1
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SHE LIVES!
My 1990 SSE started for the first time yesterday since purchase. Initially I thought it was a fuel pump problem but it turned out to be the ground wire on the factory harness that connects to the fuel sending assembly. Luckily, I was able to return the new fuel pump that I purchased because it didn't even work. It was worth the time to drop the tank anyway because the lines in the sending unit assembly are horribly rusted and crumbled in my hand. The new part is on order.
I have observed one strange thing though: when the ignition is turned on, the fuel pump does not begin pumping. It'* only after the key is in the crank position that the relay clicks and the pump turns on. This makes for difficult starting. In my wiring diagrams, it shows a "fuel pump prime" thing. The wire from this is connected to the same wire (gray) coming from the relay and going to the pump. Although the fuel system is only temporarily connected, (the tank is still on the ground and some hose clamps are omitted due to the lines breaking) I wouldn't expect the pump to behave this way. What/where is this "prime" thing?
I have observed one strange thing though: when the ignition is turned on, the fuel pump does not begin pumping. It'* only after the key is in the crank position that the relay clicks and the pump turns on. This makes for difficult starting. In my wiring diagrams, it shows a "fuel pump prime" thing. The wire from this is connected to the same wire (gray) coming from the relay and going to the pump. Although the fuel system is only temporarily connected, (the tank is still on the ground and some hose clamps are omitted due to the lines breaking) I wouldn't expect the pump to behave this way. What/where is this "prime" thing?
#2
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Posts like a Camaro
Join Date: Jul 2003
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The fuel pump is interlocked to the oil pressure sender so that if you lose oil pressure, the fuel pump will turn off. GM has been doing this since the late '70s. I put a prime button on my Sunbird but have never needed that on my computer cars. In the start position, the interlock is bypassed. GM provides the prime lead for when a tank is drained.
On our 90 the prime lead is a green female connector not connected to anything behind the battery
On our 90 the prime lead is a green female connector not connected to anything behind the battery
#3
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It seems as if I can test when the relay is activated by using a test light at that connector you speak of. This might help troubleshoot. It'* difficult to turn the ignition on and dive underneath the car when you're doing this by yourself.
Thanks for the input.
Thanks for the input.
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