02 sebring no start/stalling
 

Hey guys.

I'm having issues with my 02 2.7L sebring. I'm posting here because basically every mechanic I go to says "I don't know lol."
The vehicle stalls while driving, usually while shifting. It also will not start. I'll describe both of these separately.

Lets start with the starting issue. Sometimes when I put the key in the ignition and turn the key forward to ON (NOT start), some electrical systems will or will not turn on. Lights, certain displays on the dashboard like millage, and the air vents will turn on. However, the radio, most other lights on the dashboard like the oil pressure light, engine light, and red anti-theft light, won't turn on. When starting/on position does work, I can clearly hear the electronics in the car charging, but when it does not work there is no charging sound. Turning the key back to auxiliary does nothing - the radio doesn't turn on, nor does any dashboard lights/indicators or the air vents. Trying to turn the key over to start does nothing. The starter does not struggle to start the engine when everything is working as normal, and the battery has been recently replaced. The mechanics thought that the fuse relay box might be the culprit. After finding a refurbished relay box, the issue persists.

Now for the stalling issue. When driving, usually at speeds lower than 45mph, the car will stall. Rarely this happens while stopped but in drive gear (it's yet to happen while in park), but this usually happens when the car is shifting to another gear, but also sometimes for no obvious reason. When I say stall, what I mean is the car will shut "off" in a manner similar to that described when the car doesn't want to start - most electrical systems don't work (with some odd exceptions). Obviously the engine stops firing i.e. RPMs immediately drop to 0, although the car will continue to coast in drive gear, and I can still shift to neutral while moving and park at a stand-still. In some rare instances, the car will immediately turn back on and the engine will resume firing and driving, and in other rare instances the system will immediately charge as you'd expect in the on position, and once I come to stand-still I can put the car in park and restart the engine. Around the time this started happening, my check engine light came on. The code came back as "Generic PCM self-check fault." Some mechanics said it was rare for this code to cause any issues, and other said the only way to fix the problem, which they suspected was causing the stalling, was to replace the PCM. After replacing the PCM, the issue persists.

Any ideas/previous experience with this issue?

Least costly thing to do first would be to check and clean ALL negative cable ground connections. Not just the battery one, but NEG. to motor and NEG. to body. Next is when running have the alternator tested for output voltage, should be around 14.5V with no accessories on and maintain around 13.5 with electrical accessories turned on. It sounds like an electrical ground circuit may be causing some issues. GOOD LUCK!

Thanks for the input.
Mechanics did check ground wires. They found a loose engine ground wire, fixed it, and checked other grounds. The issue continued. They also checked the alternator, and everything looked normal. In fact, the most frustrating thing about this whole situation is everything looks normal. The transmission, electronics (i.e. computers), and other common culprits pass all their tests. Even more frustrating is they can't get the car to stall while they are testing the car D:
Any other ideas? I've seen things mentioning the crank sensor or certain belts.

As the 2.7 is a timing CHAIN motor, I doubt that is a possibility. BUT I would still suspect body ground connections. they have a nasty habit of creating an insulating coating of oxidation, so bolt/nut should be replaced and any "eyelet wire end be sanded clean and a dab of di-electric grease applied to the similarly cleaned body contact. Tight connection is not the only thing at needs here, as the modules and computer ground thru the body.
IF you are not getting specific fault codes with CEL illumination, the only other thing I would suspect to check is for a worn ignition switch, that may not be making proper contacts at the run position.

the crank sensors will cause this and the crank sensors are a weak link with Fiat Chrysler's, either throw a crank sensor at it or have a shop scan and do a wave form on the cam & crank sensors, the ECM will also do this but it would be rare