91 firebird won't turn off
#1
91 firebird won't turn off
I have a 91 firebird. It had been sitting for 7 years outside. I have put the following.
Gas tank
Fuel pump
Plugs
Wires
Battery
Heater core
Ignition switch 2x 2nd was acdelco
Starter relay
New key made by the lock smith to match
And more. The car runs a great however it will not turn off. When you turn the key off power stops to the fan and gauges. Runs fine meaning no sputtering but I need to turn off. Please help. Mike
Gas tank
Fuel pump
Plugs
Wires
Battery
Heater core
Ignition switch 2x 2nd was acdelco
Starter relay
New key made by the lock smith to match
And more. The car runs a great however it will not turn off. When you turn the key off power stops to the fan and gauges. Runs fine meaning no sputtering but I need to turn off. Please help. Mike
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Car: 88 convertible
Engine: 5.7L
Transmission: 4+3 maual
Axle/Gears: 3.07
Re: 91 firebird won't turn off
When you turn the key to "off", you should lose power to the 3 fuses marked as ECM, INJ1 and INJ2. These fuses are located in your main fuse block and should be easy to check. With no power to these 3 fuses, there is no way your engine can run. Use a test light clamped to a good ground and probe these fuses with the key in the "off" position. Report your findings. GL!
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Re: 91 firebird won't turn off
I've been there before, when mine would get to around 220 degrees it would not shut off, I used to just pop the hood and pull out the inline fuel pump fuse next to the battery to shut it off.
Since I replaced the thermostat and made it run cooler it never gets up past 200 so it doesn't happen anymore so I couldn't offer any advice on fixing it. look up the term "dieseling" on this site, this is what I believe was happening to my car, weird for a fuel injected car to do it though.
Since I replaced the thermostat and made it run cooler it never gets up past 200 so it doesn't happen anymore so I couldn't offer any advice on fixing it. look up the term "dieseling" on this site, this is what I believe was happening to my car, weird for a fuel injected car to do it though.
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Car: '89 Firebird
Engine: 7.0L
Transmission: T56
Re: 91 firebird won't turn off
My '89 has a main power switch on the steering column that is operated by a metal rod from the key switch. The key switch pushes/pulls the rod to move the electrical contacts in the box to turn the fuse panel on/off. Also, the position of that rod is adjustable and needs to be set correctly.
If I were having the symptoms with my '89 that you are describing, then I would be checking that main power switch and the rod for proper function.
If I were having the symptoms with my '89 that you are describing, then I would be checking that main power switch and the rod for proper function.
#5
Re: 91 firebird won't turn off
I pulled the three fuses as noted above. Inj1 and inj2 both nothing. Ecm with the fuse in allows power to the fuel pump as I can hear it prime. When on test Guage goes backwards. Not sure what that means except I am getting power some how even with the key off. Please let me know and thanks for the help....mike
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Re: 91 firebird won't turn off
Assuming the ignition switch is working correctly (should be verified first, as described above):
Unplug the small plug to the alternator after turning the key off. If that kills the motor, it needs an alternator.
If it doesn't, start checking the wiring for PO hack jobs.
Unplug the small plug to the alternator after turning the key off. If that kills the motor, it needs an alternator.
If it doesn't, start checking the wiring for PO hack jobs.
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Car: '89 Firebird
Engine: 7.0L
Transmission: T56
Re: 91 firebird won't turn off
It means you had reverse polarity when you measured voltage. Okay, it is obvious you don't have any knowledge of electrical. Let's try something else instead....
1. While the engine is running with key ON, pull the ECM fuse. If the engine shuts down then that is normal.
2. While the engine is running with key OFF, pull the ECM fuse. If the engine stops running then you just discovered that the fuse panel is still alive when it should be dead. In that case, the culprit is probably the main power switch that I mentioned earlier.
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Car: '89 Firebird
Engine: 7.0L
Transmission: T56
Re: 91 firebird won't turn off
Perfect, you're closing in on the problem now. That means power to the fuse panel is not being removed with key in OFF position. That main power switch I spoke of earlier is what powers up and powers down the fuse panel.
Remove the dash panel under the steering column and lower the column until you can see a metal rod going to an electrical box. There should be a way to loosen that rod (can't remember how) and move it back and forth by hand. You'll be able to feel if the switch if clicking into the on/off position and test if moving the rod shuts down the engine. Adjust the rod until the switch works when the key switch is turned on/off.
It's just nuts and bolts now... shouldn't be difficult, just need to dig in and do it.
Remove the dash panel under the steering column and lower the column until you can see a metal rod going to an electrical box. There should be a way to loosen that rod (can't remember how) and move it back and forth by hand. You'll be able to feel if the switch if clicking into the on/off position and test if moving the rod shuts down the engine. Adjust the rod until the switch works when the key switch is turned on/off.
It's just nuts and bolts now... shouldn't be difficult, just need to dig in and do it.
#11
Re: 91 firebird won't turn off
I can pull both cables off still won't kill the engine. I can slide with cables plugged in and still won't kill the engine. Only way to kill the engine is to pull ecm fuse?
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Re: 91 firebird won't turn off
All ya gotta do now, is figure out why the power to that fuse (switched ignition) isn't being turned off by any one of the 3 ign switches you've had in the car.
Did you carefully check the switch/rod adjustment, to make sure the switch is being properly operated? Although, if you can turn turn it to Start and start the car, then let it return to Run and the starter quits (it has to be at least somewhat close to correctly adjusted to do this), but then turn it all the way to Lock which is 2 entire positions back, that means that most likely there's an electrical reason for it behaving like it does.
I'd suspect some PO hacked a "kill switch" into it somehow. The usual idea being that the car won't start unless it's turned on. However, depending on how they hacked it in, they may ALSO have made it such that it's the only way to turn the car OFF as well. Which then means, all ya gotta do is, find the hackjob switch, GET RID OF IT, and put the car's wiring back like it belongs. Look VERY CAREFULLY all around the driver's seat in oddball places, hidden but where the driver can reach it; up under the edge of the console, under the seat, stuff like that.
Did you carefully check the switch/rod adjustment, to make sure the switch is being properly operated? Although, if you can turn turn it to Start and start the car, then let it return to Run and the starter quits (it has to be at least somewhat close to correctly adjusted to do this), but then turn it all the way to Lock which is 2 entire positions back, that means that most likely there's an electrical reason for it behaving like it does.
I'd suspect some PO hacked a "kill switch" into it somehow. The usual idea being that the car won't start unless it's turned on. However, depending on how they hacked it in, they may ALSO have made it such that it's the only way to turn the car OFF as well. Which then means, all ya gotta do is, find the hackjob switch, GET RID OF IT, and put the car's wiring back like it belongs. Look VERY CAREFULLY all around the driver's seat in oddball places, hidden but where the driver can reach it; up under the edge of the console, under the seat, stuff like that.
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Car: '89 Firebird
Engine: 7.0L
Transmission: T56
Re: 91 firebird won't turn off
The path of electricity is,
Battery --> main power switch --> ECM fuse --> Engine ECM
You have already demonstrated that opening that path (pulling ECM fuse) will shut down the engine. It is the job of the main power switch to open that path when key switch is moved to the OFF position. The problem has to be in that area. Either the switch is faulty (won't shut off) or somebody did a hack job on your car and hardwired around the switch.
I have been calling it a "main power switch" for clarity of communication, but it is actually called the "ignition switch" when you try to buy a replacement.
Battery --> main power switch --> ECM fuse --> Engine ECM
You have already demonstrated that opening that path (pulling ECM fuse) will shut down the engine. It is the job of the main power switch to open that path when key switch is moved to the OFF position. The problem has to be in that area. Either the switch is faulty (won't shut off) or somebody did a hack job on your car and hardwired around the switch.
I have been calling it a "main power switch" for clarity of communication, but it is actually called the "ignition switch" when you try to buy a replacement.
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Car: '89 Firebird
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