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Hello! It sounds to me like your valve timing is off. The reason the injector pulse and spark are so irratic is because your computer is so confused. The signal from the cam and crank sensor do not agree and therefore your computer has not idea when to fire the ignition coils and injectors,
The timing marks will need to be checked to verify this. I have a feeling you will find your problem here.
The valve timing can only be off that much if the chain has jumped timing, am I correct
Close... the timing chain can jump just one tooth or maybe even a few teeth. It can also break... maybe one of the camshafts is not even turning? You will just have to take a look.
Did you have any further questions?
Yes, I checked the timing chains and they are all in excellent shape. I also checked to see if they are in time and they are.
Ok... good! What do the signals look like from the cam and crank sensor when cranking the engine over? If we do not know, this would be our next step.
I will be off line for about 30 minutes... I will check in with you then.
there is some rust on the steel disc with the notchs in it for the cam sensor. Will this interfere? It does have a strong trigger signal out of the cam and crank sensors.
Does the PCM out of another car have to be reprogramed for this car. I got this computer out of a U Pull It salvage yard and the # XXXXX up. If the answer is yes, can I buy a scanner that is capable of programing computers or is this a dealer only thing. I am wanting to upgrade my code reader and this would be a perfect time to do it. Any suggestions on brands and / or how fancy I should go on the model. It's a good investment and it will definitely get used but I'm not really wanting to spend a fortune either. Also, is this black module under the dash the body control module? All of my books mention this module alot but none say where it's at. By the way, it's been nice having someone who is on the same page as me and talks the same language. THANKS!!! These computers are forever giving me fitts' Yesterday a Buick wouldn't fire the injectors and right out of nowhere it started up so we brought it home and she just called me and said it's doing it again. It's a 94 so the computer is not much help. I am leaving
Sorry for the delay! What type of scanner are you looking into getting...or are you just going to upgrade yours? What kind of money are you looking to spend?
I believe the computer may need to be programed.. but you will have to call the dealership and give them the VIN to find out for sure. If it does, I would just have them do it.
It is possible that rust may interfere with the cam and or crank sensor signal. The only way to find out to to scope each signal.
I wanted to ask you, can the factory alarm possibly be causing this chrysler to do this?
Sorry for the delay! The factory alarm should not cause certain injectors to fire as the other ones do not fire. So to answer your question, it is no.
I hope this helps. You can always accept my answer now, and repost back again later on if you have any more questions. If you want to discuss it some more just hit "reply", it's free to do so otherwise don't forget to hit "accept" and leave positive feedback if you found my answer helpful.RegardsAMEDEE
hello again. I will get back to you. Is there a scanner that is capable of programming computers for say these keys with chips in them. As for this chrysler, I am going to clean up that rusted disc and put it back together and take it to a dodge dealership here in sacramento. I would like to check the signal on the cam and crank sensors once more before I admit defeat. What method do you suggest I use to test them. What I did before was took a LED test light and put it into the signal wire at the coil plug and put the other end to the positive battery post. It seemed to work well. Do you have a better way of doing it. I am all ears and open for knowledge. Thanks and I will get back to you.
Hello! The best way to check these signals is with a lab scope. There is no other reliable way to test the signals. You need to see what the computer is seeing when you crank over the engine. As far as the scanner goes, I am not sure I understand what you mean by "chip". The DRB 3 Chrysler scanner is the correct scanner to use when reprogramming the computer.
Thanks!! much appreciated. I will get back to you. By the way, the method I used to check those sensors was the way CHILTONS said to do it. It seemed quite accurate. That is the signal. Later
Sounds good! I will be waiting for your reply!
I am just checking up on you.