1986 TPI Engine - Power Cutoff Switch
Thread Starter
Burning Brakes
Joined: May 2002
Posts: 751
Likes: 8
From: Escondido CA
1986 TPI Engine - Power Cutoff Switch
Hello Folks,
I need some opinions regarding the ECM used with my 1986 Corvette TPI engine I have installed in my 1947 Plymouth.
I have a cutoff switch installed which completely disconnects all battery power to the car. I am a firm believer in installing and using cutoff switches on all my hobby cars. However, this my first hobby car to feature any sort of computer-controlled engine management.
Does removing the power to the ECM reset all of the engine settings?
If so, how long after restoring power and re-starting the engine does it take for the ECM to 'relearn' the correct settings? Can regularly removing and restoring power to the ECM cause any harm? I've never noticed any obvious problems upon initial startup, other than an occasional slight stumble when still cold.
I am considering redoing my cutoff switch setup to include a small 3-amp bypass, which would allow current to flow to the ECM (and the stereo, and the clock) even when the cutoff switch is engaged.
Any thoughts or opinions are greatly appreciated.
Thanks in advance.
I need some opinions regarding the ECM used with my 1986 Corvette TPI engine I have installed in my 1947 Plymouth.
I have a cutoff switch installed which completely disconnects all battery power to the car. I am a firm believer in installing and using cutoff switches on all my hobby cars. However, this my first hobby car to feature any sort of computer-controlled engine management.
Does removing the power to the ECM reset all of the engine settings?
If so, how long after restoring power and re-starting the engine does it take for the ECM to 'relearn' the correct settings? Can regularly removing and restoring power to the ECM cause any harm? I've never noticed any obvious problems upon initial startup, other than an occasional slight stumble when still cold.
I am considering redoing my cutoff switch setup to include a small 3-amp bypass, which would allow current to flow to the ECM (and the stereo, and the clock) even when the cutoff switch is engaged.
Any thoughts or opinions are greatly appreciated.
Thanks in advance.
Last edited by kbuhagiar; May 6, 2012 at 09:27 PM.
Le Mans Master
Joined: Dec 2000
Posts: 7,839
Likes: 22
From: San Diego, Ca
It's either as you plan, or you'll be resetting the clock and radio buttons when you power it back up. ECM memory isn't that big of a deal. The only storage item is Block Learn and whatever it is when you turn it off remains in memory for the next restart. Now if it has a vacuum leak or other issue that requires more or less fuel, that might make a fast restart difficult, but it quickly relearns whatever fuel it needs and whatever that is goes back into memory when you turn it back off. It really isn't a set number and it will depend on how long you drive it, operating and ambient temp, so I wouldn't worry about it.
