I have a 99 stratus that just died going down interstate at 60mph. Car just cranks over, wont start, checked codes and found P1391 intermittent cmp/ckp. I checked the cam sensor and crank position sensors and they are sending out pulses. Checked ASD relay output and it has 12v out not in shutdown. I have 12v to coil pack but not seing any pulses on the ignition outputs from the pcm. Coil pack ohms out good. Does anyone know if there is any other sensor that can cause a pcm not to put out ignition pulses?

 

IDK how you checked the pulses but I've had a lot of 2.0 and 2.4's quit running due to failed crank sensors which still had a pulse but not enough signal to trigger the pcm. I used an Oscilloscope.

 

I used a scope also and crank and cam signals **** good plus it is not disableing the shutdown relay which I belive means it is seeing both cam and crank signals or it would drop out the shutdown relay and remove the 12v to the coil and injectors. I have 12v to both the coil and injectors. Going to try a used module but not sure they can just be swapped out from vehicle to vehicle without reprogramming. Going to try it anyways.

 

so what does the scope show on the ground side of the coil drivers?

are cam and crank sensors in sync and showing solid signal?

my encounters with these engines had crank signal but not in sync with cam and/or fuzzy signal.

 

Hi, I just signed up and read your post about a no-start.
I had my 98 strarus die on the interstate too. It was the tentioner pully for the timing belt bearings got to worn and wouldn't register in time and went into a no-run state. Replace the tentioner pully and started right up. Hope this helps.
Stan

 

The ground side of the coil has 12v with no pulses to ground at all. The scope I have is a single channel so not sure if crank and cam are in sync and not sure what they should look like if they were in time. The crank and cam signals are steady and clean looking waveforms. I had the timing belt changed last year when the water pump went out so wasnt thinking it was a timing problem but might be. How hard is it to verify if the timing is correct?

 

get a new crank sensor, new pcm and new wire harness, it if still doesnt start get a new car


can you screen capture the crank signal? are you checking at the pcm?

does your scanner show cam and crank sensor signal on the data stream?

I haven't seen a single channel scope for about 40 years. my scope is over 25 years old and it is dual trace.

 

Checked compression last night and found only 40lb. Cam and crank must be out of alignment. Took off cam cover and looks like the timing belt tensioner crapped, belt is real loose. Probably going to take it in to get it fixed. Same problem that sscharlie had, thanks for the help guys!