91 Grand AM LE 2.5l Doesn't Run Right When...
#1
91 Grand AM LE 2.5l Doesn't Run Right When...
91 Grand AM LE 2.5l Doesn't Run Right When the fuel pump relay is pluged in but when it isnt pluged in it runs great and for a long time.
What do you guys/girls thin could be the problem.
What do you guys/girls thin could be the problem.
#2
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Originally Posted by chevyastro4x4
91 Grand AM LE 2.5l Doesn't Run Right When the fuel pump relay is pluged in but when it isnt pluged in it runs great and for a long time.
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The the wiring to the fuel pump is shorted some where. or wait hang gm product that means that there is an alternate means to power the fuel pump.
Geez its been a long time. oil pressure switch I believe is the alternate way the pump gets power in case the relay fails. disconnect the oil pressure switch and with the relay out and tell me if you can start it.
Thats why you can start it with out the relay. you could have some bad wiring in the relay circuit or bad contacts
Geez its been a long time. oil pressure switch I believe is the alternate way the pump gets power in case the relay fails. disconnect the oil pressure switch and with the relay out and tell me if you can start it.
Thats why you can start it with out the relay. you could have some bad wiring in the relay circuit or bad contacts
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Originally Posted by chevyastro4x4
no, it is running without the relay. after i pulled the relay the pump doesnt turn on
If I am reading this correctly you are running the car then pull the relay, but if you try to start it the pump won't come on.
the engine needs to build oil pressure before the oil pressure switch will close.
#6
Originally Posted by snuckers99
The the wiring to the fuel pump is shorted some where. or wait hang gm product that means that there is an alternate means to power the fuel pump.
Geez its been a long time. oil pressure switch I believe is the alternate way the pump gets power in case the relay fails. disconnect the oil pressure switch and with the relay out and tell me if you can start it.
Thats why you can start it with out the relay. you could have some bad wiring in the relay circuit or bad contacts
Geez its been a long time. oil pressure switch I believe is the alternate way the pump gets power in case the relay fails. disconnect the oil pressure switch and with the relay out and tell me if you can start it.
Thats why you can start it with out the relay. you could have some bad wiring in the relay circuit or bad contacts
still starts there isn't any power going to the pump because it isn't kicking on and i check voltage to it and theres none
#7
Originally Posted by snuckers99
also reread this, your unclear
If I am reading this correctly you are running the car then pull the relay, but if you try to start it the pump won't come on.
the engine needs to build oil pressure before the oil pressure switch will close.
If I am reading this correctly you are running the car then pull the relay, but if you try to start it the pump won't come on.
the engine needs to build oil pressure before the oil pressure switch will close.
no, when i have the relay pull out car off, then start it with the relay out it starts but if i have the relay in and try to start it, it doesn't start just backfires
#8
I can't see how your car will run without any power getting to the fuel pump. Will it KEEP running? Or are you just starting it for a second with the relay out...in other words, using up the fuel in the lines. A car can't run without fuel...and no battery power to the fuel pump means no gas. I'm confused...
#10
Originally Posted by davzack
I can't see how your car will run without any power getting to the fuel pump. Will it KEEP running? Or are you just starting it for a second with the relay out...in other words, using up the fuel in the lines. A car can't run without fuel...and no battery power to the fuel pump means no gas. I'm confused...
with the relay out it will run for awhile, then it dies and does start again
#11
Snuckers99 is correct: the fuel pump relay is backed up by the oil pressure switch which continues to operate the fuel pump as long as there is sufficient oil pressure. I would suggest you try replacing the oil pressure switch and fuel pump relay. This is the cheapest way to go without getting into a whole bunch of diagnostics.
A fuel pump relay is only about $9 and a new oil pressure switch is around the same amount for that vehicle. Try that and get back to us.
A fuel pump relay is only about $9 and a new oil pressure switch is around the same amount for that vehicle. Try that and get back to us.
#12
Originally Posted by davzack
Snuckers99 is correct: the fuel pump relay is backed up by the oil pressure switch which continues to operate the fuel pump as long as there is sufficient oil pressure. I would suggest you try replacing the oil pressure switch and fuel pump relay. This is the cheapest way to go without getting into a whole bunch of diagnostics.
A fuel pump relay is only about $9 and a new oil pressure switch is around the same amount for that vehicle. Try that and get back to us.
A fuel pump relay is only about $9 and a new oil pressure switch is around the same amount for that vehicle. Try that and get back to us.
when i went to go get the part i told the guy there what it was doing and he says it sounds like a Fuel Pressure Regulator
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sounds like it is getting to much fuel when you are attempting to start it dont see why it would make a difference in how it ran once the oil pressure built up enough to turn on the fuel pump but it would lean it out enough at start up that could mean the difference between the engine starting or not.
doubt it is a regulator problem if the regulator was leaking you should be able to see it as it is throttle body injection, suspect a sensor not reading correctly such as coolant temp or maybe an ecm problem have you had it to a shop and had the computer scanned to see if all the sensors are reading correctly.
doubt it is a regulator problem if the regulator was leaking you should be able to see it as it is throttle body injection, suspect a sensor not reading correctly such as coolant temp or maybe an ecm problem have you had it to a shop and had the computer scanned to see if all the sensors are reading correctly.
#14
Originally Posted by bejay
sounds like it is getting to much fuel when you are attempting to start it dont see why it would make a difference in how it ran once the oil pressure built up enough to turn on the fuel pump but it would lean it out enough at start up that could mean the difference between the engine starting or not.
doubt it is a regulator problem if the regulator was leaking you should be able to see it as it is throttle body injection, suspect a sensor not reading correctly such as coolant temp or maybe an ecm problem have you had it to a shop and had the computer scanned to see if all the sensors are reading correctly.
doubt it is a regulator problem if the regulator was leaking you should be able to see it as it is throttle body injection, suspect a sensor not reading correctly such as coolant temp or maybe an ecm problem have you had it to a shop and had the computer scanned to see if all the sensors are reading correctly.
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there is no hose the regulator is right beside the injector on this tbi car and it should be fairly obvious if it was leaking gas you would see it if you had the air cleaner off and looked for any fuel leaks around the regulator.
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from the injector I would assume have you chacked for injector pulse sometimes a computer can go bad and open the injector all the time when the key is on, a noid light should flash when cranking over if its lit up solid there is a prolem probably ecm related but could be wiring shorted to ground.