Red wire on fuel pump relay

[patsfan0103]

I have a 88 Sub 350 TBI that loses prime, the autozone wirring dia shows that the red wire from the fuel pump relay should be the Fuel Pump Prime Connector. Does anyone know where this wire hooks to? Any help would be awsome, this is the first Chevy Ive had with TBI. Thank you.

[Desert1957]

I feel your pain brother,

I own an 87 with factory "TBI" I will lookup the wiring in my GM manuals Thursday morning and post what you need. Hope you can wait that long and are not broke down....

Desert

PS: You do know that when you turn the key to the on or run position you should hear the pump run for about 3 seconds , this is what re-primes the throttle body and regulator.

[patsfan0103]

That would be awsome thank you

[Desert1957]

Here is a copy from the 87 Factory Wiring Manual , It shows the wire you are talking about (circuit 490) is a switching wire back to the relay and then conects to the "ECM" (engine computer).

I will include the wiring to the "Tank Switching Valve" which show the circuit back to the sender/Fuel Pump

I know these diagrams can be hard to follow , take your time and follow the circuit number.

Hope this helps you out...

Desert

[dropd80s]

Normally the red wire coming out of the fuel pump relay allows you to hookup 12V to it and bypass the relay to see if the relay itself is bad. It is not supposed to be connected to anything, normally.