Crossfire problems
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From: Des moines Iowa
Originally Posted by jdp6000
Just to be sure follow the wires around to the firewall. they go into a box there...open the box there are 3 or 4 large connectors in there. Check them, clean them. Totally elliminate the wiring.
I'm going to guess you are not getting any fuel.
Your problem may not have been the injector at all. The ECM seldomly goes completely....they are know to act up but not go completely. First thing in the morning, open the hood, take the cleaner off, get in the car...turn the key to on...listen carefully behind you do you hear the fuel pump come on for 2 seconds??? Did you see a burst of fuel come out of the injectors (prime pulse?). If you didn't hear the pump...thats probably the problem (assuming the fuel pump fuse is good).
The pumps in these cars are bad. They don't last long. They put out very little pressure even new...about 9 psi. If you find it is the pump go with a new Delco out of an 85.
I'm going to guess you are not getting any fuel.
Your problem may not have been the injector at all. The ECM seldomly goes completely....they are know to act up but not go completely. First thing in the morning, open the hood, take the cleaner off, get in the car...turn the key to on...listen carefully behind you do you hear the fuel pump come on for 2 seconds??? Did you see a burst of fuel come out of the injectors (prime pulse?). If you didn't hear the pump...thats probably the problem (assuming the fuel pump fuse is good).
The pumps in these cars are bad. They don't last long. They put out very little pressure even new...about 9 psi. If you find it is the pump go with a new Delco out of an 85.
thanks
Melting Slicks
Joined: Jul 2005
Posts: 2,740
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From: Aurora Ontario
The 85 will work with the 82 sending unit. There are some mods to the wire connectors but not because you are going from an 82 to an 85 rather becasue the connectors have been improved. It comes with the newer style connectors. Its minor and my 85 pump from GM came with specific instructions.
Did you get voltage???
jim
Did you get voltage???
jim
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From: Des moines Iowa
Originally Posted by jdp6000
The 85 will work with the 82 sending unit. There are some mods to the wire connectors but not because you are going from an 82 to an 85 rather becasue the connectors have been improved. It comes with the newer style connectors. Its minor and my 85 pump from GM came with specific instructions.
Did you get voltage???
jim
Did you get voltage???
jim
I have'nt checked yet. I will have to get a probe first. What is the best to get?
Melting Slicks
Joined: Jul 2005
Posts: 2,740
Likes: 3
From: Aurora Ontario
Either a test light or a volt meter. Or probably both.
Get the screw driver shaped test light with the pointy end. It will have a black wire you can touch ground with will you probe with the other end. If there is voltage the head lights up.
As for a meter. You can't get just any meter. You need an automotive meter. Should have 10 ohm max impedence setting on it. They are cheap about $30.
Go over to the Crossfire site I posted. There are some very knowledgable people over there. its all about the crossfire.
Don't get discouraged. Your problem isn't a complicated one. its just a matter of figuring it out.
When cranking did you observe the oil pressure guage? Is it showing pressure??
Jim
Get the screw driver shaped test light with the pointy end. It will have a black wire you can touch ground with will you probe with the other end. If there is voltage the head lights up.
As for a meter. You can't get just any meter. You need an automotive meter. Should have 10 ohm max impedence setting on it. They are cheap about $30.
Go over to the Crossfire site I posted. There are some very knowledgable people over there. its all about the crossfire.
Don't get discouraged. Your problem isn't a complicated one. its just a matter of figuring it out.
When cranking did you observe the oil pressure guage? Is it showing pressure??
Jim
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Joined: Oct 2006
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From: Des moines Iowa
Originally Posted by jdp6000
Either a test light or a volt meter. Or probably both.
Get the screw driver shaped test light with the pointy end. It will have a black wire you can touch ground with will you probe with the other end. If there is voltage the head lights up.
As for a meter. You can't get just any meter. You need an automotive meter. Should have 10 ohm max impedence setting on it. They are cheap about $30.
Go over to the Crossfire site I posted. There are some very knowledgable people over there. its all about the crossfire.
Don't get discouraged. Your problem isn't a complicated one. its just a matter of figuring it out.
When cranking did you observe the oil pressure guage? Is it showing pressure??
Jim
Get the screw driver shaped test light with the pointy end. It will have a black wire you can touch ground with will you probe with the other end. If there is voltage the head lights up.
As for a meter. You can't get just any meter. You need an automotive meter. Should have 10 ohm max impedence setting on it. They are cheap about $30.
Go over to the Crossfire site I posted. There are some very knowledgable people over there. its all about the crossfire.
Don't get discouraged. Your problem isn't a complicated one. its just a matter of figuring it out.
When cranking did you observe the oil pressure guage? Is it showing pressure??
Jim
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Instructor
Joined: Oct 2006
Posts: 181
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From: Des moines Iowa
Originally Posted by Twin_Turbo
probe if there's [edit] 
12V at the injectors, it may very well be the ECM.
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Melting Slicks
Joined: Jul 2005
Posts: 2,740
Likes: 3
From: Aurora Ontario
Shoot...I'll have to look. You can take the wire off but I don't remember if you can get the pointy tip of the test light or meter on anything while they are plugged in. Take a look see if you can without unplugging them. If you need to unplug them it doesn't matter. You just want to see if you get any voltage. Ground one side of the test light or meter and touch each wire separately.
Jim
Jim
Melting Slicks
Joined: Jul 2005
Posts: 2,740
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From: Aurora Ontario
Looking at the manual. Looks like power goes from the ignition through the 3 amp fuses along the white to injector B and the pink on injector A.
Blue comes out of injector B and goes to the ECM. Green coming out of injector A also goes to the ECM. Sounds like you need to probe the white on one and the pink on the other.
I think if you were to follow all those wires back to the firewall and open that box I previously mentioned you will find a connector there....did you do that already???
Jim
Blue comes out of injector B and goes to the ECM. Green coming out of injector A also goes to the ECM. Sounds like you need to probe the white on one and the pink on the other.
I think if you were to follow all those wires back to the firewall and open that box I previously mentioned you will find a connector there....did you do that already???
Jim
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From: I tend to be leery of any guy who doesn't own a chainsaw or a handgun.
Originally Posted by jdp6000
The fuel goes to the rear one first. The rear one has the fuel pressure regulator in it. Just a guess but if you are getting very little fuel then the regulator will not be able to get the pressure up enough to supply both. Just because you get fuel does not mean you are getting enough..
........................................ ...........
Example...the oil pressure sensor at the rear of the motor on the driver side will cause your condition if it doesn't sense oil pressure or is defective it will shut down the injectors. When you kick it over does the oil pressure on the gauge go up over 20 psi???
First things first...check for voltage on the wires to the injectors.
jim
........................................ ...........
Example...the oil pressure sensor at the rear of the motor on the driver side will cause your condition if it doesn't sense oil pressure or is defective it will shut down the injectors. When you kick it over does the oil pressure on the gauge go up over 20 psi???
First things first...check for voltage on the wires to the injectors.
jim
Second, the oil pressure switch is a backup voltage supply to the fuel pump. The primary supply is the FPR that is switched by the ECM. Without the FPR, the engine would not start to fire until the engine was cranked long enough to generate sufficient oil pressure to cause the oil pressure switch to turn on.
Burning Brakes
Joined: Jan 2006
Posts: 1,154
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From: St Augustine FL
Originally Posted by 69427
My car is an '84, but I believe they're similar, so I have a couple of disagreements here. The rear unit has the regulator, hence it is the fuel return line. The regulator bleeds off the pressure the pump tries to create, and the regulator has to have a low pressure place to dump the excess fuel (the fuel tank), rather than to the other injector.
Second, the oil pressure switch is a backup voltage supply to the fuel pump. The primary supply is the FPR that is switched by the ECM. Without the FPR, the engine would not start to fire until the engine was cranked long enough to generate sufficient oil pressure to cause the oil pressure switch to turn on.
Second, the oil pressure switch is a backup voltage supply to the fuel pump. The primary supply is the FPR that is switched by the ECM. Without the FPR, the engine would not start to fire until the engine was cranked long enough to generate sufficient oil pressure to cause the oil pressure switch to turn on.
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From: Des moines Iowa
Originally Posted by jdp6000
The fuel goes to the rear one first. The rear one has the fuel pressure regulator in it. Just a guess but if you are getting very little fuel then the regulator will not be able to get the pressure up enough to supply both. Just because you get fuel does not mean you are getting enough..
It easy enought to check the injectors for voltage. Get a test like and probe both wires going to the injectors while some else turns the car over. It could be so many things but you first need to establish the injectors are getting voltage.
Example...the oil pressure sensor at the rear of the motor on the driver side will cause your condition if it doesn't sense oil pressure or is defective it will shut down the injectors. When you kick it over does the oil pressure on the gauge go up over 20 psi???
First things first...check for voltage on the wires to the injectors.
jim
It easy enought to check the injectors for voltage. Get a test like and probe both wires going to the injectors while some else turns the car over. It could be so many things but you first need to establish the injectors are getting voltage.
Example...the oil pressure sensor at the rear of the motor on the driver side will cause your condition if it doesn't sense oil pressure or is defective it will shut down the injectors. When you kick it over does the oil pressure on the gauge go up over 20 psi???
First things first...check for voltage on the wires to the injectors.
jim
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From: Des moines Iowa
Originally Posted by bluesilver82
Well that is how it is suppose to work...My car (82) will run with out the oil sending unit installed. Kinda scary huh? Kev Replace the fuel pump its cheap and quick. I replaced min and cleaned the tank out at the same time. It only took about 45 min and $50.00. My car would barely trickle gas throught the injectors. Fuel pump and fule filter solved the problem. Replace both. Fule filter is aout $9.00 and is located on the frame by the front side of the passenger door. It is a directional filter so make sure you install it correctly. Good Luck.
Thread Starter
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Joined: Oct 2006
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From: Des moines Iowa
Originally Posted by 69427
My car is an '84, but I believe they're similar, so I have a couple of disagreements here. The rear unit has the regulator, hence it is the fuel return line. The regulator bleeds off the pressure the pump tries to create, and the regulator has to have a low pressure place to dump the excess fuel (the fuel tank), rather than to the other injector.
Second, the oil pressure switch is a backup voltage supply to the fuel pump. The primary supply is the FPR that is switched by the ECM. Without the FPR, the engine would not start to fire until the engine was cranked long enough to generate sufficient oil pressure to cause the oil pressure switch to turn on.
Second, the oil pressure switch is a backup voltage supply to the fuel pump. The primary supply is the FPR that is switched by the ECM. Without the FPR, the engine would not start to fire until the engine was cranked long enough to generate sufficient oil pressure to cause the oil pressure switch to turn on.
Do you think it's the fuel pump then??
Melting Slicks
Joined: Jul 2005
Posts: 2,740
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From: Aurora Ontario
Guys I've change a lot of parts on my car for no reason. It may in fact be the fuel pump or the oil pressure sensing unit. I changed both. It turned out to be the connector on the injector harness that was bad.
69427...were saying the same thing just a bit different. Only the rear TBI has the fuel pressure regulator. Fuel comes in it regulates to 9-13 psi. If the pump is bad and its only getting 8 psi its not enough.
As for the oil pressure guage...mine moves upwards of 20 and towards 40 while turning the car over.
There are tests in the manual for all these things. First thing first. Are the injectors getting power...both at the harness connect point and and at the injector.
Jim
69427...were saying the same thing just a bit different. Only the rear TBI has the fuel pressure regulator. Fuel comes in it regulates to 9-13 psi. If the pump is bad and its only getting 8 psi its not enough.
As for the oil pressure guage...mine moves upwards of 20 and towards 40 while turning the car over.
There are tests in the manual for all these things. First thing first. Are the injectors getting power...both at the harness connect point and and at the injector.
Jim
Melting Slicks
Joined: Jul 2005
Posts: 2,740
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From: Aurora Ontario
I just went out and started mine. I was curious as to what the oil pressure guage did. I turned the key the oil pressure guage went to zero. I heard the pump go on for about two seconds. I heard the injectors kick in and send the prime pulse. I turned the car over the oil pressure shot up to past 20 when the car started it went to 50 psi. RPM 1400 cold.
That would mean that if you hooked up your test light or meter to one of those wires I mentioned previously you should get power to the injectors the second you turn the key to the on position.
Jim
That would mean that if you hooked up your test light or meter to one of those wires I mentioned previously you should get power to the injectors the second you turn the key to the on position.
Jim
Melting Slicks
Joined: Jul 2005
Posts: 2,740
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From: Aurora Ontario
Originally Posted by bluesilver82
Well that is how it is suppose to work...My car (82) will run with out the oil sending unit installed. Kinda scary huh? Kev Replace the fuel pump its cheap and quick. I replaced min and cleaned the tank out at the same time. It only took about 45 min and $50.00. My car would barely trickle gas throught the injectors. Fuel pump and fule filter solved the problem. Replace both. Fule filter is aout $9.00 and is located on the frame by the front side of the passenger door. It is a directional filter so make sure you install it correctly. Good Luck.
Jim
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From: Des moines Iowa
Originally Posted by jdp6000
FWIW I've unplugged mine aswell and the car continued to work. Just a guess but i think the oil pressure sensor has to send a signal of "0" oil pressure or a low number (what ever that may be) to shut the system down. Unplugging it doesn't do the same thing...no signal is sent.
Jim
Jim
Melting Slicks
Joined: Jul 2005
Posts: 2,740
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From: Aurora Ontario
Seems like it. Again I'm guessing but I think low oil pressure is not the same as no signal at all. My sensor is brand new so its not malfuntioning. My ECM is also new. Try unplugging it see if it makes a difference.
Jim
Jim