fuel pump relay remote wire 12v or ground
06-10-2016, 07:48 PM
#21
So I'm having intermittent issues with my fuel pump now. I wired everything in exactly as recommended, it worked. Crimped soldered and heat shrink everything, now it doesn't work. Check fuses and relays, still doesn't work. Come back outside a few hours later, magically works fine, multiple times. Grab my scan tool to make sure its running fine, doesn't work. Unplug scan tool, still doesn't work. I'm about ready to burn this thing to the ground.
06-11-2016, 09:13 AM
#22
TECH Resident
too early to dump fuel and find a match! 
Can you use a simple test light to check power at the pump when it is failing?
Just attached one side to the ground and the second to the 12v+ from the relay. If you have test light there, then the pump is failing.
DO you have a digital volt meter? If so, measure the voltage output at the pump.
Another test:
You should hear the relay click to energize itself even if the pump doesn't come on. Are you hearing the relay when the pump doesn't work?
Can you use a simple test light to check power at the pump when it is failing?
Just attached one side to the ground and the second to the 12v+ from the relay. If you have test light there, then the pump is failing.
DO you have a digital volt meter? If so, measure the voltage output at the pump.
Another test:
You should hear the relay click to energize itself even if the pump doesn't come on. Are you hearing the relay when the pump doesn't work?
06-11-2016, 11:41 PM
#23
Fuel pump has no power, and relay is not clicking. I had everything working and running yesterday, now it won't start.
Here's a strange thought I had tonight... I have the relay mounted with a ziptie right now. Could it be possible that the tension from the ziptie is preventing the relay from clicking?
Here's a strange thought I had tonight... I have the relay mounted with a ziptie right now. Could it be possible that the tension from the ziptie is preventing the relay from clicking?
06-12-2016, 12:23 PM
#25
Meter yes. I replaced the relay and same intermittent issues.
I removed the zip tie and made no other wiring changes. It didn't work right away, but after a few minutes started right up. I'm thinking the zip tie might be squeezing the plastic, which is keeping the relay from moving inside. Going to leave the zip tie off for a few days.
I removed the zip tie and made no other wiring changes. It didn't work right away, but after a few minutes started right up. I'm thinking the zip tie might be squeezing the plastic, which is keeping the relay from moving inside. Going to leave the zip tie off for a few days.
06-12-2016, 08:23 PM
#27
You must've had the same training I had. Haha. That was the 2nd thing I tried after replacing the relay.
It's on my buddy's property in El Cajon so I'm not out there today. Tomorrow after work I'll put a zip tie around the relay and see if that stops it from priming.
Come on down sometime if you want to see it. I take it to the El Cajon car shows on Wednesdays every now and then. Always gets lots of attention. Bring yours down and we can practice setting off some car alarms haha.
It's on my buddy's property in El Cajon so I'm not out there today. Tomorrow after work I'll put a zip tie around the relay and see if that stops it from priming.
Come on down sometime if you want to see it. I take it to the El Cajon car shows on Wednesdays every now and then. Always gets lots of attention. Bring yours down and we can practice setting off some car alarms haha.
Last edited by Grewe02; 06-12-2016 at 08:29 PM.
06-13-2016, 09:11 AM
#28
TECH Resident
you have probably done this, but I'd be verifying the call for fuel pump - ground signal - from the PCM every time I start and when it is running. If that is reliable 100%, you then narrow it down to the relay or its wiring.
maybe you have a cheap, Chinese-made relay, but it seems far fetched that the zip tie is the mode of failure. But if that is repeatable, and you can keep it from flopping around with another method then perhaps you are all set.
Not sure I can swing through El Cajon this week but keep me posted and maybe we could meet up. I think I might go over to Encinitas Cruise night this Thursday night. 3rd Thursday each month.
Doug
maybe you have a cheap, Chinese-made relay, but it seems far fetched that the zip tie is the mode of failure. But if that is repeatable, and you can keep it from flopping around with another method then perhaps you are all set.
Not sure I can swing through El Cajon this week but keep me posted and maybe we could meet up. I think I might go over to Encinitas Cruise night this Thursday night. 3rd Thursday each month.
Doug
