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Greetings to all;
I had to let loose of my ole pick up so picked up this project. I have a Haynes manual a test light a small multi meter and you all. : )))
I know info is so important so my Story is she ran till 179 thou miles and quit and for some reason got parked for a few yrs. A couple from my area bought, put fuel pump on, She ran for almost a thousand miles and quit. He did some testing ??? and figured it a crank sensor. He replaced and no start and code No Buss in odometer screen, He could not figure what next and offered it for sale.
I have heard much about wiring/ connection issues with these vehicles.
Thus far following guidelines and I verified:
When cranking, no tach movement.
I can hear the fuel pump relay kick when Plug/unplugging relay. Cheater way also switched with a neighboring one.
I unscrewed cap at shrader valve and checked for fuel which I do have, however no volt readings at fuel injectors, also have no voltage reading at coil.
Crk and Cam sensors - (Unplugged, key off) test light to ground, I have 5v on power /reference wire and 5v between sensor grnd and power/ref wire.
Key on- (still unplugged) have 5v on load/signal wire.
Crk sensor (re-connected) back probed load/signal wire cranking it goes to 0v and stays – stop crank and it goes back to 5v.
According to many that indicates a bad sensor which is possible as previous owner bought from Auto Zone (box and old sensors left in SUV). Have had and heard of many bad parts from them. But I’m not sure.
Crk sensor unplugged Test light to ground I brush light prob across load/signal wire and for the first time I hear and feel the relay Labled ASD clicking. According to Haynes manual is the coil and fuel injector one.
2 things that questions me; Key off, I do not have a parasitic drain on battery.
Key on It seems I have more than usual ark/sparking as I connect battery terminals. I ran into same thing while working on a neighbors riding mower and found the starter relay had lost a ground; Rusty connection.
Next Question - Is the No Buss (if PCM issue) affecting my test results on crank sensor as signal has to go thru it.
Sorry for the length of post.
I'm kinda at a stand still.
Best; Tom
if your using a multimeter backprobing the crank sensor during cranking it doesnt have a fast enough sample rate. try turning it over by hand with a breaker bar then check
Thank you for the interest.
It has been a while and I am lucky to have another vehicle to drive with the weather being yuk I have had periods when I got to put some time in on tinkering.
I found previous owner had misinstalled crank sensor. Jammed with weatherstrip and it made contact with reluctor ring.
I did some back yard machining of new sensor and was able to regain air gap and a control signal from sensor.
This fix now enabled me to the ASD to click and I have power to coil with a weak spark.
I have brief power to injectors but none from PCM side.
After a minute or so from turning key to (on) this power disappears.
I can shut key off and then a few minutes later turn on and same thing.
I have 5.14+- volt on TPS, MAP & crank sensors .
I hot wired for a moment an injector while the power was to other side - it released as it should.
I am trying to as close as possible feel comfortable if I have to shell out for new PCM.
I do have another question- I have battery voltage on both sides of the A/C high and low switches. Is this normal?
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