Vapor lock? - Page 2

Hey Blueshark, on my 85, the FP relay is located on the fire wall, left of the break booster and near the wiper motor. It may be in the same place on yours, I'm not sure though.

Where are you getting your pump? Autozone? If so, that more than explains it. Stay away from Autocrap parts as they are pure junk.

Guys, I will check the pump and relay this week end and report back.
 
The first two were from the dreaded autozone.  The last one was genuine GM. But I probably got the only bad one in the state with my luck.
 
For all I know I could go out there right now and the aggravatin' thing would probably fire right up.
 
Thanks for the info and replies fellas. Cheers.

The pump seams fine. I went out this after noon and it fired right up. ran for about 1 minute and stalled. The tach was fine and showed the RPM as it stalled. I tried several more times and it would not start. I looked under the hood and disconnected what I believe is the fuel pump relay. the one on the fire wall just inboard of the break booster. It made a kind of buzzing noise when the car stalled. I unplugged it and tapped on it a few times, plugged it back in and tried to start it again. Started right up and died about a minutes later. I hooked up the fuel pressure gage and tried it again. couldn't hear the fuel pump come on at all. let it set for a few minutes and tried it again. it started and ran for a minute and stalled. I watched the fuel pressure slowly drop and when it reached about 15 lbs it stalled. I found that if I just bumped the ignition but not start it the pump would come on and run for a few seconds and build the pressure up to 42lbs, normal. I bled the pressure off and I did this several times to check the pump. Bumping the ignition would make the pump come on and build pressure and the car would start. If I just held it to start it would not start until the oil pressure got up, and some times would not start at all. Each time I did this the relay that I assume is the pump relay would buzz as if it was sticking. I let the car run for some time and even went for a spin down the road and it never stalled. I noticed the oil pressure each time it would start and it would get to about 6lbs before it would start. Could the relay be sticking and causing it to turn the pump off over riding the redundant oil pressure switch?

a trick to get you home(beat on the tank with a heavy flashlight or tool for a few seconds) this is not a substitute for a new pump but it a lot of times will get you home rather than being stuck in a parking lot, and yes I have had to do this before ... but most of the time it works for me to ' limp it home is cheaper than a towing bill'

Bypass the relay on pins 30 and 87 to see if it starts or cheaply enough, buy another relay (Delco).

Installed a new relay and so far so good. Keep your fingers crossed y'all. Thanks for all the help and explanations. You've all been a great help. I'll post back if it turns out different. Cheers

If the relay fixed that, you still have a problem with the oil pressure relay. You have a dual purpose oil pressure sender/relay that it is a backup for the f/p relay. It is redundant and is under the distributor. It should have a 3 wire hookup on it (a real PIA to get out, have to pull distributor to do it.).

I was thinking about that. and was wondering if the relay sticking or fluttering would over ride that and cause it not to come into play.  Can you get to it from underneath the car?
 
Also the lead from the O2 sensor was lying on the heat shield of the Cat Cnv. and the insulation was melted, I rerouted the wire and and wrapped the bare spot. would it shorting to the Cat. Cnv. cause any problems like that?

quote:

ORIGINAL: blueshark

I was thinking about that. and was wondering if the relay sticking or fluttering would over ride that and cause it not to come into play.  Can you get to it from underneath the car?

It sounds like the car was just relying on the relay and the oil pressure switch is not working. No, the switch is under the distributor.
 

quote:


Also the lead from the O2 sensor was lying on the heat shield of the Cat Cnv. and the insulation was melted, I rerouted the wire and and wrapped the bare spot. would it shorting to the Cat. Cnv. cause any problems like that?

Yes, it would short to ground and make the car go full rich. Any black smoke @ idle?

   I figured that was the only way to get to it but thought I'd ask anyway, LOL!
 
I didn't notice any black smoke but I had noticed some black soot in the tail pipe as of late, so.....? It  may be just me but it seems to run a little beter since I rerouted the wire.  Idels smoother and a slight bit better exceleration.
 
Thanks again for the help, LB I really appreciate you takeing the time to address my questions. Don't know if I can, but if I can ever help you .......

N/P, just build a me a free boat! LOL.
 
 

quote:

ORIGINAL: mech259

N/P, just build a me a free boat! LOL.

 
Sounds fair to me.

How 'bout one like this? I call it the "Wette Vette". 60hp OB = 65mph+.


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Notice the '74 Stingray in the back.