Chrysler Repair: 1997 intrepid wont start, obd scanner, camshaft sensor


Question
QUESTION: Hi. My 1997 intrepid wont start. it has fuel pressure but no spark. there are no error codes, I scanned with a obd scanner. also the engine seems to turn over more freely and quietly than before. can you give my a diagnostic procedure I can use to find where the problem is? thank you

ANSWER: Hi Tony,
It may well be based upon what you describe about the turning over more quietly that the timing belt has broken. That would cause a loss of the rotational sensor on the cam sprockets and thus the loss of spark. You didn't mention the engine (L) but if you remove one of the covers on the front of the engine that is located where the cam sprockets are then inspect to see if the timing belt is loose/broken.
Please 'rate' my answer (see the PS below).
Thanks,
Roland

---------- FOLLOW-UP ----------

QUESTION: Thank you for the quick reply. Is there a way to confirm the issue is with the belt before taking the cover off? A test of the camshaft sensor maybe? also wouldn't the lack of signal from the cm sensor cause an error code? whatever the problem is, it happened as the car sat overnight. It was running fine one day, then wouldn't start the next morning. engine is the 3.5l. thanks again

Answer
Hi Tony,
Forget the idea of a belt breakage as the 3.2/3.5L engine is 'interference' in design and you would have heard noises of the pistons running into the valves if that did indeed happen. Also you don't have an 0340 code which says the cam signal is missing.
While you said you have pressure, you wouldn't know if you have injector pulsing unless you pulled a plug and found it to be wet. So my next suggestion is to check fuse S (20 amp) in the power box in the engine compartment* to see if it might have a subtle crack in its wire or be blown. That fuse powers the spark coil primary windings and the injectors. If it is blown then I would check the noise suppression capacitors on each of the cylinder banks to see if one of those might be shorted to ground (they are mounted on the cylinder heads and share the harness to the spark coils, their wires are dark green/light green, the same as the 12v wires that supply the coils and the injector.
That 12v supply fuse is about the only simple reason I can see for no spark (and perhaps no injector action), assuming there is no cam or crank signal fault codes.
Please 'rate' my answer and consider whether I merit a 'nomination' for voluteer of the month.
Thanks,
Roland

*This S fuse would be the fuse if your power box under the hood is wide and narrow (like the '98-on models). If the box is square (as in the '94-'96 models) then the 20 amp fuse would be fuse B. Please let me know which shape of fuse box is in your '97.
Thanks for the info.