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Ask Jeromy Madison Your Own Question
Jeromy Madison
Jeromy Madison,
Category: Dodge
Satisfied Customers: 71
Experience:  Owner/Technician at Mad Auto Repair
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I have a 1996 Dodge Grand Voyager with a 3.3 liter engine.

Customer Question

I have a 1996 Dodge Grand Voyager with a 3.3 liter engine. One morning, engine would crank, but not start. I could here the fuel pump cycling, but I squirted a little bit of brake clean down the throttle and it still would not start. I swapped ASD relay with the fuel pump relay, still no start. I checked for spark at spark plugs, no spark. I do show about 200 RPM on tach when cranking. I checked the injectors with a diode when cranking, and the diode flashes. I checked for 12 volts at coil pack, good. I check continuity from three other pins at coil pack connector to PCM, all good. I tried a new coil pack, still no spark. I think I am down to a bad PCM (coil drivers not working), however did not know if the PCM still fires the injectors and not the spark plugs. In other words, is it possible that I have a bad cam sensor?
Submitted: 1 year ago.
Category: Dodge
Expert:  Jeromy Madison replied 1 year ago.

Yes, both are possible. Are there any codes?

Customer: replied 1 year ago.
No codes. So, you are saying that the injectors will fire but spark plugs will not spark if I have a bad cam sensor?
Customer: replied 1 year ago.
Are you still there?
Customer: replied 1 year ago.
Hello, Hello, Hello....
Customer: replied 1 year ago.
I tried a camshaft sensor, still no spark. I am almost certain all that I am left with is a PCM. My only remaining question: Will injectors fire if camshaft and crankshaft signal are mismatched?
Expert:  Jeromy Madison replied 1 year ago.

What do you mean by mismatched?

Customer: replied 1 year ago.
Not synced, engine out of time.
Expert:  Jeromy Madison replied 1 year ago.

Is there any reason to believe that the engine has been disassembled since the last time it ran?

If not than there is a very low probability of that happening. I do believe that the pcm will fire the injectors seperately from the spark plugs.

Just a idea, because I have seen it before, do you have any sort of engine disabling system? Security alarm?

Customer: replied 1 year ago.
No security system and no major engine work. I know that the injector drivers in the PCM are separate from the coil drivers, however I just need to know if it is possible to fire injectors without firing the coil packs. If so, I can deduce that I have a bad PCM. Another way to look at this via a question...does the PCM need both cam and crank signal to fire injectors? If yes, then I can be certain that the PCM is receiving all the proper inputs, however not grounding the coil drivers in order to create a spark.
Expert:  Jeromy Madison replied 1 year ago.

Ok, I understand. Let me look up more information.

Expert:  Jeromy Madison replied 1 year ago.

So, have you replaced the distributor assembly?

Customer: replied 1 year ago.
There is no distributor. It has a distributorless ignition system.
Expert:  Jeromy Madison replied 1 year ago.

Ok. And you said you have replaced both the camshaft position sensor and the crankshaft position sensor, correct?

Customer: replied 1 year ago.
I have not changed the crankshaft position sensor. My question all along has been, I have tach and I injectors that are both working, just no spark. What would cause this?
Expert:  Jeromy Madison replied 1 year ago.

Yes. Your crankshaft position sensor could cause this issue. I would replace the sensor before you go any further.

Customer: replied 1 year ago.
I changed the crankshaft sensor, still no spark. I just really need to know if it is possible that the injectors work just fine, but no spark. My assumption is that if injectors are working and tach is working, then I am getting both crank and cam signals. If that is the case, then the only possible cause is a bad PCM (coil drivers).