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My 96 road e350 won’t start. I purchased it a couple of weeks ago and I’ve done some tests. Also I should mention it hasn’t run in a year. First symptom is the coil has 12 volts. When I test the spark with a spark tester it sparks constantly when I turn on the key but it’s a weak spark. No change when I crank it over. I changed the coil with a new one with no change. I can get the fuel pump to run by jumping it at the test plug under hood. Also no check engine light ever. It’s also got a new distributor. I tested the ICM and it’s getting 10 volt’s on the top wire and 4 to 5 volts when cranking so I assume the pip is ok. I’ve also cleaned all of the ground wires I could find. Is it my computer?
I forgot to mention my scanner won’t communicate with the computer. It has a obd2 connector under the dash with power on pin 16 and ground on 4. It also has an obd1 under the hood which is where I grounded the fuel pump wire which is the only way the fuel pump will come on. I also forgot to mention it’s a coachman 30 ft motor home.
I don't think you did anything wrong, but, your posts are a big difficult to follow. You say you "get spark constantly when you turn on the key". Then you add "No change when I crank it over".
Are you implying you've got spark while the engine is NOT turning over?
That is correct. It starts sparking as soon as I turn the key on. Then there is no change in the spark when I spin the engine over. The spark looks weak though. I’m using a spark tester to test.
I don’t have access to a scope but I will take pictures of the module with the connector. I think the top wire that I was testing was brown or tan. I read that the color of the module matters? I have a black one. Thanks for your help!!
I tested the wires going to the module again. I have power, I have a ground, and I have a pip signal from the distributor. So I unplugged the module and the coil stopped sparking with the key in the run position. So I have inspected the harness and I can’t find anything obvious so if I plug the module back in and unplug the computer would that tell me anything? Something is shorted and I don’t know how to find it. Thanks
Power on which Pin. Did you load test it?
Ground on which Pin. Did you load test the ground?
Do you have PIP signal while the engine is NOT cranking? If yes, describe what you are seeing.
While cranking, what do you see with a test light on the PIP pin?
Power on pin 3, ground on pin 1. I tested the coil control on pin 2 with the test light and it flickered just like at the coil with koeo and koec so the circuit there is good. I tested the pip on pin 6 with my volt meter and the voltage was all over which I would think the icm is getting a pip signal from the distributor. I’m not sure how to test the power and ground with a load?
David117... I have a different pinout for your icm. Pin1 gry/o is pip from pcm, pin2 pink is spout from pcm, pin3 is wht/p 12v from pcm, pin4 is red/lg 12v from fuse panel for hot in start/run, pin5 is tan/v to coil and pin6 blk/w is ground to distributor.
In any event, I believe you're getting false signals from the pcm to the icm as you're getting pulsing spark in KOEO position as well as no fuel pump signal. I just hate calling a bad pcm and I'm not now, just pointing you in that direction. PCM sends icm signal to pulse based on inputs from sensors. If engine not cranking should not have pulsing spark at coil.
"an open mind let's knowledge flow in and wisdom flow out for a man who has neither never listens to those who have both".
Being wrong doesn't bother me, it's being right and not understanding why that does
Ok, for giggles, pull the SPOUT connector. If you STILL have a pip signal KOEO than your problem has to be upstream from there. Can you grab a junk yard distributor and play swap-tonics?
I checked your pins with mine and they are the same just numbered different. My wiring diagram starts at the bottom of the plug with black being #1 and the top being #6. If I started at the top with #1 it would match what you have if I’m looking at it right.
I disconnected the spout connector and the coil started firing as it should. I gave it a shot of starting fluid and she started. Fuel pump still won’t run without jumping it. Does this mean I need a new computer?
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