ignitor or module
Thread Starter
Heel & Toe
Joined: Jan 2015
Posts: 24
Likes: 0
From: Caldwell
ignitor or module
Having an issue with my 84 crossfire. Started with the car clearly starving for fuel. I knew my tank was full of crap after sitting for years. I had to replace a fuel pump and put in a new sock. When it was starving it would die after riding for a bit, I would have to wait for it to settle the gunk and then it would restart. I replaced the sock again and cleaned the tank. Also replaced the filter and it gets fuel fine now and runs much better. However about every 15 minutes it dies, even under a load or going down the highway at speed. It immediately restarts. Im convinced its the module, but I realize that a spark control module is present as well. Not sure of its function but either way something is causeing my car to die about every fifteen minutes. Driving me crazy but I dont just want to throw parts at it. But I don't have access to any easy way to test these, does it sound familiar to anyone?
Race Director
Joined: Mar 2015
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Having an issue with my 84 crossfire. Started with the car clearly starving for fuel. I knew my tank was full of crap after sitting for years. I had to replace a fuel pump and put in a new sock. When it was starving it would die after riding for a bit, I would have to wait for it to settle the gunk and then it would restart. I replaced the sock again and cleaned the tank. Also replaced the filter and it gets fuel fine now and runs much better. However about every 15 minutes it dies, even under a load or going down the highway at speed. It immediately restarts. Im convinced its the module, but I realize that a spark control module is present as well. Not sure of its function but either way something is causeing my car to die about every fifteen minutes. Driving me crazy but I dont just want to throw parts at it. But I don't have access to any easy way to test these, does it sound familiar to anyone?
I would change the filter again
Last edited by antfarmer2; Apr 8, 2015 at 06:13 PM.
Burning Brakes
Joined: Oct 2005
Posts: 849
Likes: 1
From: Shelbyville IN
From personal experience....double check that short rubber hose between fuel pump and modulator. Mine had a leak that wouldn't show up until my car had run for a few minutes. I had your symptoms. A cheap fix.
Pro
Joined: Jan 2003
Posts: 706
Likes: 47
From: Denver Colorado
You need fuel, spark and air to run. Check your spark when it stalls, check your fuel pressure both at idle and under load... it should ideally be steady at 13 psi. A lot of 1984 fuel pumps are marginal at 9 to 11 psi which results in poor performance. If trash got into your fuel pressure regulator when the fuel was dirty you could be suffering low pressure. First, isolate the problem as spark or fuel when the car stalls.
Thread Starter
Heel & Toe
Joined: Jan 2015
Posts: 24
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From: Caldwell
You need fuel, spark and air to run. Check your spark when it stalls, check your fuel pressure both at idle and under load... it should ideally be steady at 13 psi. A lot of 1984 fuel pumps are marginal at 9 to 11 psi which results in poor performance. If trash got into your fuel pressure regulator when the fuel was dirty you could be suffering low pressure. First, isolate the problem as spark or fuel when the car stalls.
From the previous post there is no vacuumn hose to the ignitor from the pump. The pump is in the tank and has three lines fuel feed, return, and a vent. The ignitor has no vacuum hose at all unless Im looking at something besides the ignitor
Burning Brakes
Joined: Feb 2013
Posts: 1,173
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From: norway
Pro
Joined: Jan 2003
Posts: 706
Likes: 47
From: Denver Colorado
Fuel has already been resolved, Thats why I am zeroing in on fire, specifically The module, coil or ignitor. Maybe I wasnt real good at explaining this. While driving down the road the car dies in gear and I can immediately restart then it drives great for 15 minutes until it does it again. I can jump out on the freeway and check everything but as it restarts no condition is persistent to be tested. I get fuel and fire. My knowledge base isnt that limited, and Im sorry if I dont sound appreciative. The issue is so specific that it seemed that it would be easily recognizable by soneone who has had the same problem. One last symptom. After the car is warmed up it doesnt like to restart, but after cranking it will fire up and run fine, just doesnt want to restart right off the bast.
From the previous post there is no vacuumn hose to the ignitor from the pump. The pump is in the tank and has three lines fuel feed, return, and a vent. The ignitor has no vacuum hose at all unless Im looking at something besides the ignitor
From the previous post there is no vacuumn hose to the ignitor from the pump. The pump is in the tank and has three lines fuel feed, return, and a vent. The ignitor has no vacuum hose at all unless Im looking at something besides the ignitor
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Thread Starter
Heel & Toe
Joined: Jan 2015
Posts: 24
Likes: 0
From: Caldwell
I tried a new coil, no change. Last night I found a vacuum leak which I located under the drivers headlight, it was connected to an unknown module next to the vapor canister. After that I woke today to the car running great, until after work then back as it was. I did notice a new development the fuel range/instant fuel mileage indicator is saying 99/80 respectively and doesn't change. When the car is running good its normal, rough the readings are clearly a malfunction. How does the ECU determine fuel mileage or does it? Is there a sensor wondering if it might be vacuum based as well
Tech Contributor
Joined: Jun 2004
Posts: 20,847
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From: I tend to be leery of any guy who doesn't own a chainsaw or a handgun.
Fuel has already been resolved, Thats why I am zeroing in on fire, specifically The module, coil or ignitor. Maybe I wasnt real good at explaining this. While driving down the road the car dies in gear and I can immediately restart then it drives great for 15 minutes until it does it again. I can jump out on the freeway and check everything but as it restarts no condition is persistent to be tested. I get fuel and fire. My knowledge base isnt that limited, and Im sorry if I dont sound appreciative. The issue is so specific that it seemed that it would be easily recognizable by soneone who has had the same problem. One last symptom. After the car is warmed up it doesnt like to restart, but after cranking it will fire up and run fine, just doesnt want to restart right off the bast.
From the previous post there is no vacuumn hose to the ignitor from the pump. The pump is in the tank and has three lines fuel feed, return, and a vent. The ignitor has no vacuum hose at all unless Im looking at something besides the ignitor
From the previous post there is no vacuumn hose to the ignitor from the pump. The pump is in the tank and has three lines fuel feed, return, and a vent. The ignitor has no vacuum hose at all unless Im looking at something besides the ignitor
I've got an '84 and I have no clue what you are referring to.
Race Director
Joined: Apr 2002
Posts: 10,036
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From: Anaheim CA
Race Director
Joined: Apr 2002
Posts: 10,036
Likes: 346
From: Anaheim CA
Thread Starter
Heel & Toe
Joined: Jan 2015
Posts: 24
Likes: 0
From: Caldwell
Does that then suggest that if im seeing 99mpg and 80mpg on instant and these never fluctuate that the ECM might be failing? And that might as well explain the poor performance
Thread Starter
Heel & Toe
Joined: Jan 2015
Posts: 24
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From: Caldwell
Well after a coil, cap, rotor, module, I finally came to the conclusion that based on how the ECM forwards the mileage signal to the dash I replaced the ECM and BAM..... solved. Runs great no more stumble or dying. I have had a battery drain and installed a cut off. But I think repeated jump starts and voltage spikes killed the ECM. It was intermittent so possibly connection related but regardless SHE IS BACK!!!!
Burning Brakes
Joined: Feb 2013
Posts: 1,173
Likes: 152
From: norway
Well after a coil, cap, rotor, module, I finally came to the conclusion that based on how the ECM forwards the mileage signal to the dash I replaced the ECM and BAM..... solved. Runs great no more stumble or dying. I have had a battery drain and installed a cut off. But I think repeated jump starts and voltage spikes killed the ECM. It was intermittent so possibly connection related but regardless SHE IS BACK!!!!
