94 Cap full gas gauge - no start.

[mom_of_davian]

4.3
Replaced recently
Fuel pump
Filter
Plugs
Wires


This has happened before. No symptoms. I don't have a full tank. If I let the car sit a day it usually starts fine and will be fine for a while. Could it be the fuel relay?

[j cAT]

Originally Posted by mom_of_davian

4.3
Replaced recently
Fuel pump
Filter
Plugs
Wires


This has happened before. No symptoms. I don't have a full tank. If I let the car sit a day it usually starts fine and will be fine for a while. Could it be the fuel relay?

with a vehicle this old replacing the fuel pump relay with the fuel pump is what should have been done also if you used an airtex pump this maybe the problem. first find out if it is a fuel or ignition problem . when it fails to start put the fuel pressure guage on it. you need 43-47 psi . .

now if you have an ignition problem this maybe due to the water pump leaking into the distributor.

also check the battery wire that feeds the under hood fuse box. this connection of this wire at the fuse box is a well known failure.

on the plug wires what brand did you use ? only use ac delco wires. the other wires sold do not have the correct resistance wires with high resistance will damage the distributor/ignition system. the resistance should be 800-1200 OHMS.

[mom_of_davian]

Relay was not the problem, replaced and still no start.
I am getting spark and have only used AC delco wires.

[j cAT]

Originally Posted by mom_of_davian

Relay was not the problem, replaced and still no start.
I am getting spark and have only used AC delco wires.

with spark now you have to measure the fuel pressure. with no pressure I would check for power loss/blown fuses/open wire/connector. with low fuel pressure the pump would be suspect.

use a voltmeter to check for power at the fuses/relay/fuel pump connector.

you can get a pressure gauge at most autozone stores.

being intermittent it is most likely electrical. ground connections can also cause these issues.

check the wiring harness in the trunk on the passengerside near the rear tail light for any damage etc.

[mom_of_davian]

Turns out I have an Airtex pump. Going to test it and see what the outcome it.

[Joseph812]

My dad had a 95 Caprice Classic. If the fuel in the tank was less than something like 1/4 full, it had a tendency to not start. We didn't know that, so this was a vexing problem until one day my brother either found out about it or solved it, I forget which, but I seem recall that the neighbor across the street wanted one and already knew about the tendency in that car model. It didn't stop him from offering to buy the car from my brother, though.

[mom_of_davian]

So, replaced the fuel pump after replacing it 2 days ago. We were getting 18 psi. This time it started right up and drove up the road great, pulled into the driveway and again. Tank read full and it died on me. Started right back up. I don't want to chance driving it if it's going to act up again. It's got to be electrical and don't know if its something shorting out the pump or what but even if the gauge is incorrect the pump should still work right. Any suggestion on where to start check loose connections/grounds?
Also checked FPR and re-replaced filter.

[j cAT]

Originally Posted by mom_of_davian

So, replaced the fuel pump after replacing it 2 days ago. We were getting 18 psi. This time it started right up and drove up the road great, pulled into the driveway and again. Tank read full and it died on me. Started right back up. I don't want to chance driving it if it's going to act up again. It's got to be electrical and don't know if its something shorting out the pump or what but even if the gauge is incorrect the pump should still work right. Any suggestion on where to start check loose connections/grounds?
Also checked FPR and re-replaced filter.

one thing you do not state is the voltage readings at the pump. also the pump requires secure wiring/soldering. no half aZZ wire connectors.