Crossfire problems
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From: Des moines Iowa
Crossfire problems
I have a 82 with crossfire injection system. When i got the car it ran great and soon after it started missing so I removed the air cleaner only to see that the front injector was'nt spraying fuel. I replaced the injector and started the car. The new injector sprayed fuel but now the rear injector was'nt spraying. I walked away frustrated and the next night I tried to start the car and neither injector sprayed!!! Could it be the computer????
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check the fuses 1st but they are most likely not the problem. Check the wiring harness all the way to the firewall. The injectors get a constant [edit] 
-> 12V and are activated by grounding (injector driver)
-> 12V and are activated by grounding (injector driver)
Last edited by Twin_Turbo; Oct 19, 2006 at 05:42 PM.
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From: Dayton, Ohio
I would blame the computer yet.Make sure you have fuel in the tank,use a flashlight and NOT a 110 volt droplamp.The 82 was bad for the gauge going bad and the pump itself.When you turn the key on does the injector spray for a second or two?Let me warn you up front my help to you will be limited,I usually refer to the 82 manual and go though GMs procedures.Hopefully some more knowledgable guys will chime in.
Edit -somebody like TT
Edit -somebody like TT
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From: Des moines Iowa
Originally Posted by DWncchs
I would blame the computer yet.Make sure you have fuel in the tank,use a flashlight and NOT a 110 volt droplamp.The 82 was bad for the gauge going bad and the pump itself.When you turn the key on does the injector spray for a second or two?Let me warn you up front my help to you will be limited,I usually refer to the 82 manual and go though GMs procedures.Hopefully some more knowledgable guys will chime in.
Edit -somebody like TT
Edit -somebody like TT
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From: Des moines Iowa
Originally Posted by Twin_Turbo
check the fuses 1st but they are most likely not the problem. Check the wiring harness all the way to the firewall. The injectors get a constant 5V and are activated by grounding (injector driver)
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From: I tend to be leery of any guy who doesn't own a chainsaw or a handgun.
I don't have an '82 repair manual, but 5 volts is generally signal voltage or sensor supply voltage. I would expect there to be 12 volts on both sides of the injector connector (when attached to the injector)when the controller IC in the ECM is not turned on (but ignition turned on). When the injector turns on there should be 12 volts on the high side and just a few volts on the ECM side due to the voltage drop across the injector.
Please correct me if I am wrong.
Please correct me if I am wrong.
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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 Twin_Turbo
Of course it's 12V... d'oh
good thing I don't have a crossfire anymore
I blame it on the Erdinger Weizssbier
good thing I don't have a crossfire anymore
I blame it on the Erdinger Weizssbier Weizsbier, that's good stuff!
and 1/2liter bottles...woohoo! ...did I have 5 or was it 12...I don't know 
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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.
12V at the injectors, it may very well be the ECM.
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From: Dayton, Ohio
Originally Posted by Kev82vette
Is there any way to tell if ecm is bad? When I first started having this problem I checked the ecm fuse and when i put it back it the fuse box It was'nt pushed in all the way. I tried to start the car and neither injector sprayed. Thats why now I think it might be the ecm.
Melting Slicks
Joined: Jul 2005
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From: Aurora Ontario
Originally Posted by Kev82vette
I checked the fuses and they were good. I have checked the wires and they look good. Thanks
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.
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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.
Melting Slicks
Joined: Jul 2005
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From: Aurora Ontario
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
Melting Slicks
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From: Aurora Ontario
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From: Burlington WI
I am not familar with crossfire system but with all the fuel injection cars
I had I would take a fuel flow test and pressure test with fuel lines disconnect from system. Most GM's I had you could screw a pressure gauge into the fuel rail but some cars including toyota I seperate the feed line some place and ran both flow and pressure.
I know on my buicks and toyota that the pressure had to get to 25lbs
before the injector would open but on your system its not over 13lbs.
I would clean my injectors with a 30lb freon can with 35 pounds of
regulated pressure into the can. Can had 4 or 5 cans of injector cleaner
from K mart with about 1 gallon of premium gas. I met a guy on the
road one day as I just fill a gas can for my lawn mower and he was stuck at a traffic light. We took the air cleaner off and pour some gas
right down the throttle body and it started. We could keep it running
as long as I would pour a little fuel into it but would stop when I didn't.
I suspected a bad fuel pump.
I had I would take a fuel flow test and pressure test with fuel lines disconnect from system. Most GM's I had you could screw a pressure gauge into the fuel rail but some cars including toyota I seperate the feed line some place and ran both flow and pressure.
I know on my buicks and toyota that the pressure had to get to 25lbs
before the injector would open but on your system its not over 13lbs.
I would clean my injectors with a 30lb freon can with 35 pounds of
regulated pressure into the can. Can had 4 or 5 cans of injector cleaner
from K mart with about 1 gallon of premium gas. I met a guy on the
road one day as I just fill a gas can for my lawn mower and he was stuck at a traffic light. We took the air cleaner off and pour some gas
right down the throttle body and it started. We could keep it running
as long as I would pour a little fuel into it but would stop when I didn't.
I suspected a bad fuel pump.
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Instructor
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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