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Injector Question 81 deville

2K views 11 replies 5 participants last post by  nyshark 
#1 ·
So i've had one problem after another since buying this car

1981 sedan deville with the 6.0 v8-6-4 decommisioned

Replaced the timing chain, got it in time, wouldnt fire, found i had no fuel pressure, replaced the pump and filter fixed that

i still have a draining battery for some reason but enough about all that

I'm having an issue with the injectors

if i take off the injector harness, the driver side dumps fuel like theres no tomorrow into the throttle body as i try and crank it over, starts up and idles til it stops dumping fuel or i turn it off

passenger side nothing comes out

if i connect the harnesses back to the injectors it continuously tries to crank til the battery dies, and i dont believe fuel is released

i tried hooking up a noid light to the harnesses, didnt see a flash at all on either of them, i then tried a multimeter with a max setting for the voltage (thinking maybe the noid light was burnt out) but it just gave me an overload error (i think it was in millivolts)

the nod light led me to believe its electrical, but the dmm lead me to believe its getting juice cause it said overload

the other weird thing is that the windshield wipers will turn on, without touching the switch while i have the key in the run position, not sure if that was with the harness hooked up to the injectors or off or what, just something i noticed, along with the fan turning on for heat/air without touching any of the buttons



some of this is making me think that maybe the ecu is bad, but i dont even know where the ecu is on this vehicle, this car has been nothing but a head ache for me thus far so i'm hoping someone can help

thanks,
alc
 
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#3 ·
I feel ya brother...... I have been through all this when I got my 81 Fleet. about five years ago. With the fuel issue it could very well be the ECM most likely the PROM. The throttle body unit has an internal fuel pressure regulator which could be the culprit. I had my ECM completely rebuilt and I overhauled the throttle body as well and now it runs like new. First of all post all the codes that you get coming up on the Climate Control Center then we can take it from there. Battery draw down could be the internal voltage regulator on the generator or diode issue,,,,bad grounds could also cause this,,,,trunk lite , under hood lite,etc staying on. You will be awhile tracking this one. Do you have any of the factory service manuals yet???? Your ECM is under the glove box, just for your info. Easy to remove form it's bracket. Lay on the floor and look up you will see it mounted on the dash.
 
#4 ·
well safari, that's one of the issues, I cant get the climate control to read the trouble codes, I get the two dots but nothing else ends up displayed, which is one reason I had the thought of a bad ecm

and my uncle (whom I bought the car from) said that at one point someone found a bad ground in it, it wasn't him so he doesn't know which ground it may possibly be

i'd like to carb it but i'm not sure how easy that is with the other electronics on the car, it cant be as easy as just slapping a carb on after taking the throttle body off, lol
 
#5 ·
I think you are right about the carb. and the ECM. I think the first gen. ECM was the one for carbed cars. The best time spent on these old girls is to go over all the grounds that you can physically find. Pull the fastener, wire brush them and then put a smidge of dieelectric grease and then tighten them back up. You could also put on a battery disconnect on one terminal and then it's a quick turn for off and a quick turn for on until you get the time to troubleshoot more on the parasitic draw.
 
#10 ·
I tried installing a high performance accel coil , and the car behaved like it was possesed i put the old original coil back and it ran perfect but now after 200 miles or so it has begun to accelerate for no reason the engine just revs up i keep it in neutral at lights I am open to any ideas i respect your input thank you i am willing to change anything that may be causing this so fire away thanks
 
#12 ·
Today i will put a new throttle spring in $5 and a new ICM in distributor $45 I feel that these are needed and then if the problem persists I will buy a new ECM I think that high output coil from accel cooked some things it never had this problem until i tried putting the high output coil in . who knows really how much voltage it was throwing out but when old coil was put back in the car ran fine 200 miles and just started having similar acceleration without touching gas peddle.
 
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