cranks no spark 3.8 town and country

[repoman]

Well first time posting so hope i do it right.
I tried to start my 1996 town and country van the other morning to let it warm up, it was near 0 deg out. The van tried to fire on the first crank then when on to just turn over. I tried to get it to start after that and it just cranks over. Every once and a while it tries to fire. but only at the first turn of the key switch. I asked the local auto parts store and they thought it was the crank and or the cam sensors. So what the heck i got both and replaced them one at a time. still nothing. I have a spark tester (the kind you plug in spark plug cable and it lights up when you get spark) When i have my wife turn the key to the on position i get a flash in my tester, it is really weak light and it goes out, Then when you crank the motor over i might get one quick weak flash out of my tester but it wont do it everytime you try. (this happens on all 6 wires from coil)Went the next step replaced coil pack. new pack is the same as old one. I was told how to check flash codes and i got 12,55 codes, 12 is something about having the Battery input to PCM disconnected during last 50 key starts and 55: Completion of fault code display. So that has been no help to me. While i was messing around I noticed that there was a small wire loom with 6 wires in it had rubbed on the trans housing and melted the wires together, 3 of the wires went to the crank sensor and the other 3 go to a plug that held by a bracket right above the trans, i matched the colors of the wires and spliced them all with butt connectors. after that i still had the same thing at the coil. I also switched relays around in the fuse box under the hood to see if that might be the problem. I seem to have good fuel psi, turn the key on with the bleeder pressed and it shoots out alot of gas. I am thinking it might be something simple that i am over looking.

[jdl]

Can you check for B+ at the coil pack? Does the primary connector at the coil pack have 4 wires? The dark green wire with an orange tracer should have voltage with the engine cranking, does it?

[1thunder]

pcm faulty common on that year with that engine

[repoman]

I checked the wires to the coil and yes i have power in the green and orange wire when cranking.

[1thunder]

yes and the other 3 wires should dwell the coil witch is controlled by the pcm and if all the other crank and cam sensor inputs are there then the pcm is not doing it's job

[jdl]

Originally Posted by repoman

I checked the wires to the coil and yes i have power in the green and orange wire when cranking.

It is my understanding the computor won't ground the ASD relay unless it sees the crank and cam signal. The fact that you have voltage at the coil pack shows the computor did ground the circuit. On the connector at the coil pack, you can put one end of the test-lite on the voltage terminal and the other end on one of the other terminals, they are grounds. Crank the engine, how does the test-lite react? If you get nothing, the computor isn't grounding the circuit for some reason. If the lite doesn't pulse, then the computor isn't switching the circuit for some reason. If you think the ground circuits are faulty, you could take the circuits loose at both ends and do an ohms test. You could wiggle the connector on the computor end, all that may be a waste of time. Thunder may be right, you may have a computor issue.

[repoman]

I get nothing when i tried the wires with test light like you said. I will move on to your 2nd sugestion. Now that i ran out of time to work on it tonightI was wondering is there such a thing as a Battery cable going bad in the inside where a guy might not be able to see it. Could that cause the problems. I will check that after work if you guys think that might be the cause, I have the main ground and two smaller wires comming off the ground cable i dont have a clue where the two smaller wires go i would suppose one might go to the PCM . If its something that simple I will kick my own butt.

[repoman]

By looking at your thread I see that you have gone thru the same problem i'm going thru right now. I wonder if you have solved it and if you could give some tips as to what causes this. I have changed the cam and crank sensors, coil pack, tried 2 pcm's from scrap yard (though they're off 3.0L engines) and all I get is a spark to one of the coils and some light back firing. 96 Grand Voyager 3.3 no spark

Best regards,


Well on my 96 Town and country,i think i have figued out what the problem is. PCM like some of the other guys had said, But on my van i guess it must be vary common i cant seem to be able to find one for it. Parts stores here in Omaha, Nebraska Tell me that that part is a critical core meaning I have to send mine in to be rebuilt and sent back to me. Well that also means i will have to wait more than a week to get it back) Some of the parts stores also said something about needing to have the darn things flash programed with the van info like vin number ect i dont know if that is true yet or not anyone have info on that? Can you just plug in a PCM with the same part number in and go? But anyway this is what i get on mine. I checked the green/red wire at the plug to coil pack. I took my test light and hooked one end to the + side of my battry and tested the other 3 wires in the plug to coil pack. (make sure not to touch the hot wire in there the book says) I have 2 wires that flash a vary weak light while cranking and one wire that is grounded all the time cranking or not The test light stays on all the time(think it was the blue/grey wire that was doing that. As far as using pcm from 3.0 on your 3.3 96 Grand Voyager, sounds like you might not be getting the right one for your van what i have heard so far it wont work but i dont know that for sure. I will put this under my Post and maybe someone can think of something else that might help us both.

[1thunder]

3.0l pcm will not work and could cause other problems not good to install on a 3.3l vehicle
3.0l have 1 coil and a distributor 3.3 has a coil pack
and pcm will need vin and odometer entered and depending on version supplied may need to be flashed should check the dealer may surprise you on the cost may be cheaper than aftermarket here in canada it is

[aldovera]

Originally Posted by 1thunder

3.0l pcm will not work and could cause other problems not good to install on a 3.3l vehicle
3.0l have 1 coil and a distributor 3.3 has a coil pack
and pcm will need vin and odometer entered and depending on version supplied may need to be flashed should check the dealer may surprise you on the cost may be cheaper than aftermarket here in canada it is

Well, I went out and got me one remanufactured from the dealer ($557. cdn. including taxes here in Toronto) since I was certain that the PCM was the culprit. Anyway, my original PCM was dead for sure, but the ones I tried from the 3.0 seemed to have some life. So I plugged the new one in and I'm all geared up to go whoo hoo! NOT SO FAST. The dammed thing is doing the same as the other ones. Only grounding one coil. As you can Imagine I wanna shoot myself. I was at my last straw, I almost called a tow truck to take it to the dealer. I remembered that on the cam sensor I replaced (albeit used one) I had placed I little piece of paper to use as a spacer and I held it to the tip of the sensor with some oil. I Thought may be it was causing some interference with the signal. I pulled the sensor out and voila! the paper is still there intact so I put back in and pressed it to make sure it sat all the way in. THERE cranked engine up and boom! engine is purring like a kitten. So repoman if you changed your sensors ( and new ones come with the paper spacer glued to them which will disolve after the engine starts running ) make sure your cam one is sitting properly or your PCM won't read it and it won't give you a not detecting code either.

[thebertman]

I seem to have an 100% identical situation to the one described. Can anyone describe or point to an online diagram what the PCM is and how to replace it? What do these things cost?

[Taz480]

Aldovera, are you saying you think maybe you didnt get the cam sensor all the way down?? I know I had trouble getting mine to even go in with the new O-ring. With reasonable force and some light tapping on the end of a rod w/ the other end on the sensor, it popped in. I assumed it was all the way down. It drove like brand new for about 400 miles. O_o
Here is my thread:
http://www.automotiveforums.com/vbul...4&page=2&pp=15
Could possibly be the problem with mine. Couldn't hurt I guess to loosen the sensors and try to reseat them. Thanx.