View Full Version : Toyota 1993 Corolla fuel pump problem
stevent
Nov 18, 2010, 03:23 PM
I have a 93 Corolla that just stopped. No noise coming from fuel pump. Replaced pump and checked main relay and circuit opening relay. Both seem to check out according to manual. Still no noise at fuel pump. Any ideas. Thanks
kitch428
Nov 18, 2010, 06:19 PM
If the CEL comes on with key on, then at least we know the computer's alive. If not, we got trouble.
The rest would be electrical wiring problems leading to the pump.
The DLC under the hood will allow you to jump the fuel pump on (pin B+-FP) with KOEO.
This will allow you to check fuel pressure. All you mention is "noise".
That is only heard after start attempts, you know that, correct?
stevent
Nov 19, 2010, 06:25 PM
No, on everything else I own, including turf equipment where I work, you hear pump when the key is turned on. My wife's plymouth van was also like that when we put new pump in. Says same in my Toyota manual. I'll try cranking and then listen. Thanks
kitch428
Nov 19, 2010, 07:20 PM
Ok, just so you know, Toyota fuel systems work on sustained pressure. Pressure is held with a check valve in the pump after shut down.
The pump will prime, but only while the key is held to "crank".
Then you only may hear it for a second after.
Try my idea of jumping the check connector under the hood.
Then you can "run" the pump for hours on end if you like with the key on, engine off. (koeo)