Fuel system failure after emissions test pass
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From: Concord, CA
(Fuel system failure after emissions test pass) Fixed
I suspect fuel pumps or filter clogs, as it starts and runs on ether if you hold the MAP open part way. Also I heard the MAF open and close on the wood spar used to get air pass the MAF for ether/air ratio. The fuel rail was 50 psi and now it is 15 and falling so the injectors are now effectively dry 
Help anyone.
Help anyone.
Last edited by Andre Hedrick; Jun 25, 2008 at 02:32 AM. Reason: Problem solved!
Burning Brakes
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From: Chilton Wisconsin
Jumper the fuel pump relay to be sure that you are getting power to the pump.
Assuming that you are getting power and the pump is running but not developing pressure check for pump flow. If you have flow but no pressure it is a regulator problem - if you have no flow you have a pump problem.
Assuming that you are getting power and the pump is running but not developing pressure check for pump flow. If you have flow but no pressure it is a regulator problem - if you have no flow you have a pump problem.
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Jumper the fuel pump relay to be sure that you are getting power to the pump.
Assuming that you are getting power and the pump is running but not developing pressure check for pump flow. If you have flow but no pressure it is a regulator problem - if you have no flow you have a pump problem.
Assuming that you are getting power and the pump is running but not developing pressure check for pump flow. If you have flow but no pressure it is a regulator problem - if you have no flow you have a pump problem.
Not sure if you have an in tank pump, but if you do, it can cause blockages when it decides that the parts don't want to stay together.
Jumper that relay and work your way forward. Hell, it could be a blocked fuel filter, and my friend, that would be the cheap fix.
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From: Stockton, CA
Andre
When my fuel pump "died" it would run briefly.....then the impedence would spike (measured across terminals on pump) and it would die.....I think the brushes or brush springs on the pump were dying....so effectively no fuel or not enough was getting sent forward....new pump fixed it!!! But I only have 1 pump
When my fuel pump "died" it would run briefly.....then the impedence would spike (measured across terminals on pump) and it would die.....I think the brushes or brush springs on the pump were dying....so effectively no fuel or not enough was getting sent forward....new pump fixed it!!! But I only have 1 pump
Burning Brakes
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From: Chilton Wisconsin
They are easy to make. A 2 terminal one is nothing but a short piece of wire with a blade terminal on each end. A 3 terminal one is similar except it has three pieces of wire with the blade terminal on one end with the three joined together on the other end.
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From: Ball Ground, GA
If you want to do it nicely, procure:
- two feet of lamp or zip cord (the two-conductor stranded electrical cord used to hook a table lamp to the wall outlet)
- a single-pole, single-throw toggle switch with "OFF" and "ON" clearly marked.
- two 1/4" male flat spade connectors.
Put the switch on one end of the lamp cord, the connectors on the other end.
When testing a relay, insert one connector into the "30" (always-hot battery bus) or "15" (switched power from the ignition switch) terminal in the relay socket, the other connector into the "87" (load) terminal. In the fuel pump relay socket, the pump should run when the switch is on and power is on the other connector.
Earlier cars require two "87" connections for the pump relay. You can just add a short jumper and another connector to the first "87" terminal.
- two feet of lamp or zip cord (the two-conductor stranded electrical cord used to hook a table lamp to the wall outlet)
- a single-pole, single-throw toggle switch with "OFF" and "ON" clearly marked.
- two 1/4" male flat spade connectors.
Put the switch on one end of the lamp cord, the connectors on the other end.
When testing a relay, insert one connector into the "30" (always-hot battery bus) or "15" (switched power from the ignition switch) terminal in the relay socket, the other connector into the "87" (load) terminal. In the fuel pump relay socket, the pump should run when the switch is on and power is on the other connector.
Earlier cars require two "87" connections for the pump relay. You can just add a short jumper and another connector to the first "87" terminal.
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From: Concord, CA
Okay fuel pump works, relay may be bad. With the cover off, I can force the relay on and the pump kicks the pressure back up to 50 PSI, but no start.
The next question is related to the MAF, how many turns out from all the way in should it be?
Also Wally, if 87 is not loaded then it will not start?
The next question is related to the MAF, how many turns out from all the way in should it be?
Also Wally, if 87 is not loaded then it will not start?
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From: Concord, CA
Rebump
Got another FP relay and still does not power up the pump, next is the AFC relay.
I am dead now with no idea how to proceed, have walked through the WSM section 1-20 and now completely lost on what went wrong
Could the DME just croak and it still fire on ether?
Got another FP relay and still does not power up the pump, next is the AFC relay.
I am dead now with no idea how to proceed, have walked through the WSM section 1-20 and now completely lost on what went wrong
Could the DME just croak and it still fire on ether?
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From: Concord, CA
Replaced FPRelay and that works now, still injectors no spray.
Checked the behavior of FPRegulators with a vacuum gun and they cause the pressure to drop by 20% and each works independently.
Off to replace the AFC relay.
She still attempts to run with a squirt of ether so we have fire to the plugs.
Checked the behavior of FPRegulators with a vacuum gun and they cause the pressure to drop by 20% and each works independently.
Off to replace the AFC relay.
She still attempts to run with a squirt of ether so we have fire to the plugs.
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From: Jersey Shore, USA
Hey Andre,
I don't know if I can help, but can I just try to sum up what's been tried and done?
This is for an '81, right?
Originally, fuel rail read 50psi, and was running OK.
Then when it wouldn't run, the fuel rail pressure gauge read 15 psi.
You tested the FP Relay, found it to be bad, and when it was replaced, you got 50psi at the fuel rail again.
Car still wouldn't start and run on it's own though.
Next you replaced the AFC Relay, and still no help.
At each interval, you used starting fluid to test for spark, and it would turn over and run briefly each time.
Somewhere along the way you adjusted the MAF screw and aren't sure where it was originally.
Does that pretty much cover it?
Did you try anything else along the way that might have affected the operation (Timing? Vacuum check? Grounds?). I'm only asking because it's possible that the fuel pump relay was the problem, but in the process of trying to fix it, something else may have gone out of whack.
At any point did the ether cause ignition up through the intake? I've heard of people blowing the intakes right off their engines and worse with that stuff. If that happened, anything could be fried or just loose.
Hopefully this will clarify it or your responses will spur someone to think of something that will help.
I don't know if I can help, but can I just try to sum up what's been tried and done?
This is for an '81, right?
Originally, fuel rail read 50psi, and was running OK.
Then when it wouldn't run, the fuel rail pressure gauge read 15 psi.
You tested the FP Relay, found it to be bad, and when it was replaced, you got 50psi at the fuel rail again.
Car still wouldn't start and run on it's own though.
Next you replaced the AFC Relay, and still no help.
At each interval, you used starting fluid to test for spark, and it would turn over and run briefly each time.
Somewhere along the way you adjusted the MAF screw and aren't sure where it was originally.
Does that pretty much cover it?
Did you try anything else along the way that might have affected the operation (Timing? Vacuum check? Grounds?). I'm only asking because it's possible that the fuel pump relay was the problem, but in the process of trying to fix it, something else may have gone out of whack.
At any point did the ether cause ignition up through the intake? I've heard of people blowing the intakes right off their engines and worse with that stuff. If that happened, anything could be fried or just loose.
Hopefully this will clarify it or your responses will spur someone to think of something that will help.
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From: Concord, CA
Hey Andre,
I don't know if I can help, but can I just try to sum up what's been tried and done?
This is for an '81, right?
Originally, fuel rail read 50psi, and was running OK.
Then when it wouldn't run, the fuel rail pressure gauge read 15 psi.
You tested the FP Relay, found it to be bad, and when it was replaced, you got 50psi at the fuel rail again.
Car still wouldn't start and run on it's own though.
Next you replaced the AFC Relay, and still no help.
At each interval, you used starting fluid to test for spark, and it would turn over and run briefly each time.
Somewhere along the way you adjusted the MAF screw and aren't sure where it was originally.
Does that pretty much cover it?
I don't know if I can help, but can I just try to sum up what's been tried and done?
This is for an '81, right?
Originally, fuel rail read 50psi, and was running OK.
Then when it wouldn't run, the fuel rail pressure gauge read 15 psi.
You tested the FP Relay, found it to be bad, and when it was replaced, you got 50psi at the fuel rail again.
Car still wouldn't start and run on it's own though.
Next you replaced the AFC Relay, and still no help.
At each interval, you used starting fluid to test for spark, and it would turn over and run briefly each time.
Somewhere along the way you adjusted the MAF screw and aren't sure where it was originally.
Does that pretty much cover it?
The MAF was adjusted with the car running too to, then removed an blown out for junk material from age. I have good idea about the MAF setting, and I have a second MAF used for testing that is untouched. Other than that, you are on target.
Did you try anything else along the way that might have affected the operation (Timing? Vacuum check? Grounds?). I'm only asking because it's possible that the fuel pump relay was the problem, but in the process of trying to fix it, something else may have gone out of whack.
PS When did you become a LIFER?