DESPERATELY need main fuel relay for my '95 Prelude

uberNoobZA · Post by **uberNoobZA** » Tue Nov 21, 2017 9:14 pm

I think I've fried my main EFI relay while I was tidying up some hanging cables under my dash (I think the 'professional' that installed the alarm / immobiliser did something that left this hanging loose) by shorting the solder points on the back while tucking it away. Reason I suspect this is that the engine has always started firsttime every time, and just 2 minutes earlier, it started, I then remembered I wanted to tuck the loose stuff away, so turned off engine, tucked it all away (I might have left sterro / ignition on - can't remember) and then car wouldn't start. I also can;t hear fuel pump priming anymore.

I'm desperate to get a replacement before this weekend, any chance someone has one lying around ? Willing to pay for it (obviously) and collect it if not too far.

firstlude · Post by **firstlude** » Tue Nov 21, 2017 9:36 pm

hi have you checked the alarm fuses and any fuses relating to the fuel pump just incase one of these has blown, not being a 5th gen owner not familiar with the wiring , i had a similar issue with one of my 4th gens i thought i had a faulty fuel pump relay did some testing and bypassing turned out i had lost a trigger feed from the main ecu

uberNoobZA · Post by **uberNoobZA** » Tue Nov 21, 2017 9:48 pm

Fuses all seem fine, though I don't seem to find any fuse relating to fuel pump. It's a 4th gen btw

Most likely cause to me seems to be that I shorted the relay, as it only happened after I was fiddling around under the dash with the relay, trying to hide it out of the way. Happy to get a known working relay anyway, to at least try and if nothing else, rule out the relay being the issue.

That said, if you could tell me how to bypass the relay as a test, I'd be happy to try that. Or maybe specific fuses to check ?

Post by **newkid** » Tue Nov 21, 2017 9:55 pm

vanzep has plenty. Sure he can sort you out.

firstlude · Post by **firstlude** » Tue Nov 21, 2017 11:12 pm

sorry didnt realise yours was a 4th ,i have tried to put a link to the manual for testing the relay but it dont seem to wont to play mind you i am pants on a computer, right pin 1 is +12v from battery , pin 2 is - ve or ground , pins 3 and 8 are from ecu , pin 5 is ignition live, pin 6 is starter signal , pin 7 is fuel pump, if you pull the plug off the relay and link pin 1 and pin 7 of the plug this should make the fuel pump work dont leave the pump running unless engine is ,, as far as fuses go i pulled all mine out one at a time and tested them with a meter as i find a visual check can sometimes miss a blow fuse i also found that some fuses had been replaced with the wrong ratings so corrected this as i went , another thing to bere in mind is this relay does suffer from dry solder joints inside so could even be this so if you can solder pull the relay apart and freshen up the joints

uberNoobZA · Post by **uberNoobZA** » Wed Nov 22, 2017 7:30 am

Thanks. Will try that

Post by **Drax** » Wed Nov 22, 2017 1:10 pm

i have a spare if your desperate bud, but its my spare so ill either need it back at some point or if yours is proved faulty then post the faulty one to me and i can re solder the points to hopefully make it work again

Post by **vanzep** » Wed Nov 22, 2017 3:28 pm

thats one sent out to you via next day courier

ive sent u a pm with the tracking info.
its a resoldered one so should give you years of use without worry

Merlin did the resoldering for me on a batch of 3 or 4 of these a couple of months ago

uberNoobZA · Post by **uberNoobZA** » Wed Nov 22, 2017 3:48 pm

vanzep wrote:thats one sent out to you via next day courier
ive sent u a pm with the tracking info.
its a resoldered one so should give you years of use without worry
@Merlin did the resoldering for me on a batch of 3 or 4 of these a couple of months ago

You're a life saver !!

89 UKDM BA4 4WS (resto job!) · Post by **wurlycorner** » Thu Nov 23, 2017 8:52 am

Would be very surprised if you'd damaged the Relay tbh - more likely is broken a wire on the connections to it? (or a fuse as others have suggested). Check fuses in the engine bay fuse box, Not just the footwell one
The relay is easy to test and easy to open up to inspect for damage, so have a look at that first.