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As the title states I have a very random intermittent no start issue. I have tracked the problem down to the fuel system. I first thought it was due to lack of pressure (at times pressure gauge reads zero after a prime). I have changed everything there is to change. crank sensor/ wiring to crank sensor (preventative/just in case)/ fuel pump/ fuel filter with regulator/ fuel pressure sensor/ and fuel pump relay. I still get a random intermittent no start that resolves itself within 15 minutes of sitting. The only thing I can say is when it happens the pump is effectively dead. no prime, no noise, nothing, like someone unplugged it. then out of the blue it primes and off I go from wherever I may be stranded. It also only appears to rear its big ugly head when the car is fully warmed up and after i get to a destination and shut it down. Then when I go to crank it up it just cranks and cranks. Then I guess it snaps out of its brainless slumber and cranks right up. random electrical gremlin? dme relay getting flaky? does anyone have any ideas or experience with this extremely frustrating situation?
I can say im a decent mechanic however electrical is not my strong suit...but something is telling me this may be my problem. I have a hole clean through my power wire to pump and some degradation in the insulation on the ground wire and power wire at the connector. Im guessing this problem comes up when the car is "hot" because the wires are also hot from running for awhile and this causes arcing? electrical gurus I ask for guidance. Also should I re-wire or use liquid electrical tape to cover degradation parts
Last edited by Scottyboy225; Jan 2, 2017 at 09:50 PM.
Looks like it to me Scott .Can you remove the plug, and cut off the bad part of the wires and then re fit the leads back in the plug . With the damage on the wires can the short be inside thats doing this .
It looks like someone used a test light at one time to check on voltage. It does not look like any of the wires were pierced completely through. Just some liquid electric tape should ease your concerns.
Mike T.
the hole actually goes all the way through on the power wire. the first picture is of a light i have shining through the hole. I spent some time while at work today looking for a new connector but I didnt find any so I guess ill deal with it the old fashion way. I haven not owned the car for very long but boy has it been a head ache getting straight.
Last edited by Scottyboy225; Jan 3, 2017 at 03:48 PM.
another swing and a miss. repaired the damaged wires, cranked her up took her for a spin ran perfect. bring it to the house because at this point I dont trust it anymore. I shut it down and let is set for about 15 minutes and AGAIN sputters to life then dies. I KNOW the pump was not running it was just running on residual pressure. wiggle my work and it didnt fix anything, wiggle the relay board in the trunk...no go. random attempt 10 minutes after banging my head against the steering wheel presto ignition pump primes fires right up no CEL's. man this is driving me nuts
Scot is that the rear of the fuel pump in the picture with wires showing? Can you wire a bulb up to the power supplyfor the pump .And put the bulb in the car so you can see it .I did this once on a Saab i had , it keept cutting out .By doing this i knew it was the pump or the fuel relay after bulb went out . If light stops on and it stops ,your pumps faulty Did you check the fuses ? may be 2 fuseboxes on your model.And a fuse you missed out.
to all it may concern or anyone who may run into this issue. I have resolved the issue, turns out the internal fuel circuit within the main ecu had a fault that presented itself once the car was hot. This could have been caused by the wiring issues I uncovered during my hunt for the gremlin. The final resolution after repairing the wiring issues was unfortunately to buy a new ECU and have it synced to the car which was a bit pricey but now she runs great with no intermittent issues. Thanks all for the help and to anyone who is currently going through this issue I hope my notes can help in your troubleshooting!
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