Fuel pump won't come on / No start

Callmewhitexr7

Registered User
Ok I have a 93 SC and it just stopped running, well I know now that the fuel pump isn't turning on when I turn the key on so I checked to see if it would kick on by jumping the two wires from the relay and the fuel pump came on but still the car wouldn't start I changed out the relay and still no start. I've ruled out the Ignition switch and inertia switch what else could cause this problem Someone please help this is my only vehicle.. Thanks everyone...



Nick
 
are you sure the fuel pump came on? id lean towards fuel pump but if it came on then hmmmm... Id hook up a fuel pressure guage and check the fuel at the rail with the pump jumped to see if it builds up pressure, because it should start for a second or two if there is left over pressure, even if the pump doesnt run when you try and start.

Option #2, spray starting fluid in the intake tube and have someone try and start the car as you're spraying, should kick on for a second or two.

Go from there :cool:
 
I'm positive that the fuel pump came on because i had the lines off and it shot gas out, plus i could hear it. So what is spraying the starting fluid in the intake going to do I know the pump isn't coming on, I just don't know why come on people I need some help. lets get this sc back on the road... but I am going to try the starting fluid. and also if the pump was bad wouldn't it not turn on at all..
 
ok, silly question. where are you getting the fuel at? you said you had the lines off, where? could it be that your fuel filter is clogged? I had a a damn fuel pump no start problem that I chased for a week. turned out that I never fully seated the harness on the pump itself and the damn thing would sometime make contact and sometimes not. how much gas do you have in the car? maybe your gauge gave u the ghost and you're just bone dry?

Rick
 
The filter isn't clogged and I have enough gas but I tried to run the codes and nothing happens the check engine light doesnt even come on the fan doesn't kick on and you can jump the wire for the fuel pump under the hood and nothing happens also the ground wire that goes from the battery to the radiator support where does the other wire run to? I'm thinking I have a ground fault somewhere but not sure anyone got ground diagrams???
 
I just want to see if the car starts with the starting fluid thats all, because if it wont start with that then you may be looking at other issues.

It should start for a second or two before it stalls.


BUTTTT I'll post some troubleshooting for you.

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PINPOINT TEST A: FUEL PUMP DIAGNOSIS
A18 CHECK EEC RELAY AND WIRING

l Key OFF.
l Remove EEC Relay.
l Key ON, Engine OFF.
l DVOM on 20 volts.
Check relay socket for voltage at Pins C1, or C2 and A or NO.
l Note which pins have voltage present (there should only be voltage on one pin if each pair, if voltage present on both pins of one pair, look for shorted wiring).
l Are voltages greater than 10.5 volts on relay socket?

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A21 CHECK VOLTAGE AT PIN 22 (PROCESSOR)


l Key OFF.

l Battery fully charged.

l Remove EEC-IV processor.

l Install Rotunda Breakout Box, T83L-50-EEC-IV, or Rotunda EEC-IV Monitor 007-00018 or equivalent.

l Key ON, engine OFF.

l DVOM on 20 volt scale.

l Measure the voltage on Pin 22 of the breakout box, or with EEC-IV Monitor, install the appropriate overlay according to engine size and year. Place selector switch "A" on Pin 22, "FP", turn EEC-IV Monitor power on and read voltage on Pin 22 from LCD readout.

l Is voltage greater than 10.5 volts?

Yes
CHECK processor for malfunction. After condition is corrected, GO to «A2».

No.
SERVICE wire between EEC-IV and FP relay/IRCM. CHECK at VIP connector for lead presence. GO to «A2» when condition has been corrected.

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A17 CHECK CHECK POWER SUPPLY TO FP RELAY


l Key OFF.

l Remove fuel pump relay.

l Key ON, Engine OFF.

l DVOM on 20 volt scale.

l Check relay socket for voltage at Pins C1, C2, and A or NO.

l Does relay socket have voltage at 2 pins as indicated?
 
Also check the engine ground in front of the battery, it comes from the negative cable, when i unhooked mine i had majooor problems, MAJOR haha.
 
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