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Discussion Starter · #1 ·
I was driving my 84 vette to work today because my water pump went out on my truck.

anyway it started to rain hard, i was on the freeway going about 45... visibility was minimum. A minivan cut me off, i ended up slamming my breaks and hydroplaning out of control into a ditch. The car shut off and would not start. I cant hear the fuel pump charge up. it will start with starting fluid but wont stay running. i tried disconnecting the battery for a few minutes with no effect.

what could cause this? bad relay? computer fuel shut off? any ideas on how to fix it?

thanks in advance for any help

Craig
 

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I don't know the connection between sliding in the ditch and the fuel pump quiting, but when they do quit - it is usually just like that...they quit with no warning.

If it will run off starting fluid - then you nailed the fact you don't have any fuel getting in the engine.

Before getting too deep, jack up the car and examine the fuel lines along the passenger frame rail and make sure you didn't some how damage the feed line and kink it closed.

If all is well there get a fuel pressure gauge from you local autoparts store. Your 84 operates off about 9-12 PSI or so of pressure. You should see the pressure spike when you first turn on the key. It could be it is working, but if it is only putting out 3-5 psi or so, it won't be enough to start.

There are a couple of things that will cause it not to cycle on.
**assuming you checked the fuse first**
1. Bad pump
2. Bad relay
3. computer/wiring issue

I am not 100% sure on the 84, but I do know that by 85 the fuel pump was wired through the oil pressure switch. If it sees no oil pressure it won't run the pump. So, here is what I would suggest.

If the pump is original, or been there a long time - go ahead and change it. They are not that expensive and don't take very long to do since you can access it from the gas tank lid on top. Make sure you stop by your GM dealer and get a new gasket to replace the old one as the aftermarket or even GM pumps don't come with the Vette gasket.

I would also suggest you replace the fuel pump relay. On the 85 that is on the firewall right beside the windshield washer motor - not sure on the 84. These are standard maintenance items that won't hurt to replace if they are original.

While changing the relay you can test the wires coming to it and make sure it is getting power and signals to trigger it.

If you are still without pressure - your problem goes deeper - but this is a good start.

70% of the time it is the pump, 20% of the time the relay - and 10% of the time the oil pressure switch is bad not keeping the relay closed for pump operation.
 

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Discussion Starter · #3 ·
ok, i gave it an oil change, i noticed my gauge read 5 psi for oil pressure when the key is in and not running, usually it would read 15. it is back at 15 psi now. I checked the relay and that tested out good. i checked every fuse in the car the day it happened, all were good. I checked the fuel lines for kinks or breaks and didn't see any.

I did notice after i changed the oil, i could hear the fuel pump turn on now but still won't start. I will test the fuel psi tomorrow and let you know how it turns out.

when the fuel pump turns on, should the rubber gas line get hard so you cant squeeze it? right now it is soft.

Thanks for all the help
Craig
 

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I never tested the feel of the lines, but it is such a low pressure system, I doubt it gets all that hard. The 85 and up models will have 40 PSI or so surging through those lines - so those would really get stiff.
 

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Discussion Starter · #5 ·
sorry it took so long, i have been busy.

I went and bought a new fuel pump. when i took the old one out i noticed that the rubber thing that connects the fuel pump outlet to the metal tube came off. I went ahead and replaced the fuel pump anyway as long as i had it all apart. once i was finished, she started right up.

Thanks for all the help,
Craig
 
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