Help! Car died. Fuel pump not priming. SOLVED: Main Relay
#1
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From: Charlotte, NC
Help! Car died. Fuel pump not priming. SOLVED: Main Relay
Ok so I'm stuck in the city. I pulled into a gas station to get something and when I got back in the car it won't fire. I can hear that the fuel system is not priming when I turn the key. Turns over fine but will not start. I checked the fuse and it's fine. What else can I look into that signals the fuel system to turn on? I'm running hydra 2.17 FWIW. There have been a few time in the past where when I am driving the Ecu seems to lose power for moment and the car fires right back up. Jeremy at FM said that some of the older hydras have a twitchy 5v power supply that can go bad. Id rather it not be that so I'm looking for some other things to check before takin the down time to send the ecu back to hydra for diagnostics.
#7
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From: Charlotte, NC
Rev- if you're right, I'll PP you $20 lol (seriously). I'm up for just a moment and will go down to the car in a bit. I had a hell of a night and took 2 Tylenol pm at like 3am....I'm going to sleep the rest of this off.
Where is the main relay again? Oh ---- why am I asking, I have sprinted FSM in the garage.
Where is the main relay again? Oh ---- why am I asking, I have sprinted FSM in the garage.
#12
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From: Charlotte, NC
I'm going to end up buying a spare one to keep in the car....Rev is going to make me paranoide with his third relay failure lol
The failure on mine was the pin that runs to the side that gets switched...it got so hot it turned the pin blue. Maybe the diode **** out? I understand how a relay works, but don't know how one side (don't know if it's main power coming in or going out) could get that hot without flipping a fuse.
The failure on mine was the pin that runs to the side that gets switched...it got so hot it turned the pin blue. Maybe the diode **** out? I understand how a relay works, but don't know how one side (don't know if it's main power coming in or going out) could get that hot without flipping a fuse.
#19
Keith Tanner had the main relay fail on his V8 Targa car during the event last year. In this post he seems to suggest that it's a not-infrequent failure on Miatas of all vintages:
http://www.flyinmiata.com/projects/t...ld.php?UID=212
--Ian
http://www.flyinmiata.com/projects/t...ld.php?UID=212
--Ian
#20
I actually haven't had one die on me (stock ECU everything), I thought it did though one time. Wasn't getting power to fuel pump, picked up a relay from Alex/2ndchanceroadster but while there, tested mine on his race car and it started up fine. Went back home and his relay worked on my car.
Days later, fuel pump dies, but wasn't the pump. The fuel pump assy wiring burnt a hole the ground wire to the FP, the plastic clip crumbled (literally) trying to pull it out. The positive wire was perfectly fine. As I said, I'm a noob w/ electronics but i'm guessing it has to do w/ the relay... maybe sennding too much power, overheating the ground wire? There's a burn mark on the plastic that the interior fuel tank wiring plugs into..