injector controll?
Thread Starter
Racer
Joined: Jun 2005
Posts: 341
Likes: 1
From: Akron Ohio
injector controll?
hey guys i have an 86 vette that is turning all of the injectors on when the key is turned on. they stay on as long as the key is on. what would be causing this, the computer? i know how bad it is to get to the computer so i am hoping it may be something other than that. any ideas anyone have this problem before? thanks for you help
Safety Car
Joined: Sep 2003
Posts: 3,599
Likes: 24
From: Orange County NY
St. Jude Donor '10-'11-'12-'13
What method did you use to determine that the injectors were "on" when the key is in the on position? Do you mean they are getting voltage or actually firing? What problems are you experiencing with the car?
Le Mans Master
Joined: Feb 2006
Posts: 8,753
Likes: 9
From: Louisiana
Exactly, when the key it turned on you should hear a humming noise. This is the fuel pump priming the fuel system. That is all that happens when the key is turned on. There should be no power going to the injectors until the key is in the crank position. Power is sent to the distrubitor and when the plugs start firing, the ECM reconizes the pulse counts from the distrubitor and sends pulse counts to the injectors.
The injectors only receive circuit counts after the engine is rotating. The fuel pressure that was built up in the system during fuel pump priming is then sent into the combustion chamber via injectors. If power is sent to the injectors when the key in on then there is a problem, either wiring or ECM. The FSM (factory service manual) for your year car will make it easy to troubleshoot the problem, if there is one. I have a 86 vette as well and would be willing to look in the FSM to help with a little more info as to what is happening.
The injectors only receive circuit counts after the engine is rotating. The fuel pressure that was built up in the system during fuel pump priming is then sent into the combustion chamber via injectors. If power is sent to the injectors when the key in on then there is a problem, either wiring or ECM. The FSM (factory service manual) for your year car will make it easy to troubleshoot the problem, if there is one. I have a 86 vette as well and would be willing to look in the FSM to help with a little more info as to what is happening.
Thread Starter
Racer
Joined: Jun 2005
Posts: 341
Likes: 1
From: Akron Ohio
i swapped the computer and now the injectors are working properly but when i plug in thePCV valve into the valve cover the car surges at idle between stall and 1200 rpm but it idles fine with the valve out. any ideas with this one?
