bnoland

Ok, I have been fighting with this car for about two weeks now. Its a 1993 Ex coupe all stock 5 speed. At first the fuel pump wouldn't come on unless you jumped the blk/yel to the yel/grn wires at the main relay. That made me think it was the relay so I replaced it. The car started the first time, shut it off and then wouldn't start again. This time it wouldn't even start by jumping the wires. I checked the wires up till they go into the main loom under the dash to see if they had a small break making it work sometimes and not others. I pulled on them pretty hard and none of them broke so I don't think there is an issue there. Then I tracked it back to the ECU.. the typical water in the floor and burnt spots on the ECU so time for another ECU. I got the ECU in, plugged it in and still no fuel pump came on. I went and got another main relay (autozone warranty) thinking maybe I had burnt the other one up. Put it back together and still nothing however with the good ECU I can now jump the wires and it will start again. It was stuck at my wifes grandparents so I jumped the wires so I could at least get it home to work on it.

I have a good ECU and a good relay but the fuel pump still won't come on unless I put a jumper wire on the blk/yel - yel/grn at the main relay. What else could it be??

bnoland

Any ideas??

ekhatchc5

damn that sounds like a tuff one sounds like somethins not hooked up right but u prolly checked that. any fuses, could be a bad ground somewhere wish i could help though

bnoland

I thought that too but the thing that throws me is when I jump it around the relay the pump works. Ground could be an issue I think but I would think that cause other issues since that relay controls other things as well. I am stumped.. anyone have some good wiring diagrams? Maybe I can find something there to check. My thought is that the relay is basically loop so I wouldn't think there is anything else between it, the ECU, and the pump but I dont have a diagram so I can not confirm this. The dash lights don't work ether if that makes a diffrence though I haven't checked them since the new ECU so they may be working now.

Former User

If you jump the Yel/Wht wire to the Yel/Grn wire in the main relay plug, does the fuel pump prime?

bnoland

I havent tried that combo, I will give that a try and update on here. If it does what does that mean?

onunez65falcon

I have the exact problem, it start it last year, pump start acting up so I got a new one, it work few weeks and start doing the same thing them I change the fuel pump relay and the same, everything that happen to you, it happen to me.
I own two identical car, 2 Honda Del sol 1.6L same year, same everything, so I starting swapping part from the good car to the Bad one and everything work on my good car(relay’s, fuel pump, distributor etc) but the bad car still have the same problem with the all the part from the good car.
Please tell me that you figure out the problem on yours.
Any ideas

bnoland

I still havent tried this but what will this tell me if it does? It runs if I connect the Blk/Yel to the Yel/Grn at the relay. That is how I got it home.

Honda'sAreDank

Did either of you guys figure this out? I'm having the EXACT issue in my CRX.