My white T would not start one morning last week. Traced down to no fuel pressure, after I verified the pump was good I started to dig. Car would start and run with fp prime connector. That told me the wiring was ok back to the tank. Swap relays no go, break out schematic start checking voltage, found Ecm commanding relay but no power on other side. This is where it get weird. The fp/inj fuse feeds the relay /oil psi switch/and injectors according to the schematic. Checked the fuse it was blown, replaced no issues cars starts everytime. Anyideas...do I have a ghost?
Blew the 15amp FP/inj fuse
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Phoneguy
Cometic HG stress tester
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- Aug 27, 2002
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How old is the pump? Stock hanger? I have seen the wiring fried on the hanger bulkhead.
Bryan
Bryan
I had that happen on Meg's Dad (John's) GN, I have a 340 from 2006 maybe 15k miles. Since the stock harness only powers the relay for the hot wire kit it would not blow that fuse if it was the pump. It would blow the hotwire kits fuse near the alternator.
Phoneguy
Cometic HG stress tester
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well that leaves the injector harness...
Bryan
Bryan
Not surprising ... after 27 years of being heat soaked and vibration ... the insulation wears through... its amazing to see how brittle and dry rotted the wires are on the stock harness ... cheap insurance to replace them.
And what would you say if I told you it's a casper's newer harness less than 5yrs old...damn buicks...I'll just rewire the whole car!
And what would you say if I told you it's a casper's newer harness less than 5yrs old...damn buicks...I'll just rewire the whole car!
It's still worth a look to check it over ... it still may have worn or rubbed through and shorted to ground .. worth a look
oil psi switch wiring ??
Phoneguy
Cometic HG stress tester
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LOLAnd what would you say if I told you it's a casper's newer harness less than 5yrs old...damn buicks...I'll just rewire the whole car!
Hey I have had more than my share of shit with this car !! Hopefully Im good to go now. We have had nothing but crazy weather here...snow, ice , freezing rain, sub zero temps.....
single digits now with ice yesterday and snow now
Bryan
Mine did the same thing while I was driving it. Was able to pull into restaurant I was going to, have dinner and check out car afterwards. Never did figure out why and it never happened again. It did give me the idea for one more theft deterrent tho
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There is another possibility or 2.
Since this is a 15 amp fuse, it is possible that it could just give up after 25+ years, and especially since all the wiring and connectors are also getting older and creating more resistance in the circuit which will over work the fuse at times.
This has happened in many GN'sI have worked on, and a new fuse usually cures the issue if it does not immediately blow again.
One place to check as well is the oil pressure connector as oil and age can cause resistance and even a short there.
Since this is a 15 amp fuse, it is possible that it could just give up after 25+ years, and especially since all the wiring and connectors are also getting older and creating more resistance in the circuit which will over work the fuse at times.
This has happened in many GN'sI have worked on, and a new fuse usually cures the issue if it does not immediately blow again.
One place to check as well is the oil pressure connector as oil and age can cause resistance and even a short there.
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X3 oil pressure sensor
Thanks Pat.
