I have a 95 dodge Neon SOHC, It stalls after hitting operating temp. It starts when cold like a champ and drives great till it starts to stall. When It starts Ill notice my tachometer will sporadically hop around, At idle it could hop up to 4k though no change in RPM, the engine will be misfiring for afew seconds then die out. Usually within 1min I can restart then duplicate the stall. When the engine stall I do not smell gas.

This is a temperature dependent issue.

New parts:
Fuel pump, filter
Crank sensor and wire harness
Cam sensor and wire harness

Tests Ive done:
TPS, nice linear voltage output and does not fluctuate when the engine stalls.
Have 49PSI at the fuel rail, all injectors are click and work fine till it stalls.
Coil tests good at 14k and .7 ohms, also within speck after heating up.
Coil wiring to PCM test ok, no shorts and no High ohm wires.


Limped home from work stalled several times.
Codes:
12
54
11
43
11
43
55

Replaced the Cam sensor
codes:
12
11
54
11
55

Then I replaced the cam sensor, now if I shut the motor off on the first glitch but not a full stall I only get engine codes:
12
11
55

I got that twice in arrow, then I got on the third test:
12
55

I check the battery connections. They are Very clean, good connection to the fuse panel, and I have an added ground wire.

So my codes point to the PCM and Coil.

I really don't think it could be the coil, I tried to simulate a coil failure by unplugging it but that makes it smell like gas when it stalls and the real stalling problem does not smell like gas. I also can not figure out how the coil could confuse the PCM to make the tachometer hop around like it does when it stall.


Tonight Im gonna spray some electrical cold spray on the sensors to try and find the temperature related failure.

I hope its not the $$ PCM. any ideas? Test?

 

Low voltage in my Shelby Z made all the gauges go nuts. I have heard that they have issues with coil problems after 70,000 miles or so. It could simply be a degradation of spark and not a total loss of spark, they are subjected to a lot of heat being attached to the top of the motor at the rear where the exhaust is. They should have at least put in a spacer plate to reduce heat soak into the coil. If you replace it, get the MSD coil for it. [sm=smiley20.gif]Here's a link to the MSD coil: MSD Coil

 

The dealer just called and they said it is the PCM (computer).

They want $475 for the diag (100), computer (275), and computer install and programming (100).

I found one in the junk yard in town for $65 (programmed) I might pickup.
7 other yards in town do not have any Neon computers left, selling for like $75-150.
I also may take a look inside my broke computer. Often just a cracked or failed solder joint, or a visably cracked glass diode could cause this kind of temp related failure. The dealer said once I open the case I should be able to see the Circuit Card, so its not fully encapsulated in plastic or rubber and could be repairable.

 

Just find one in a junk yard or for sale that is for the same year, motor and transmission that your is and you will be fine. It is an easy swap and it's a helluva lot cheaper than the dealership.[sm=smiley2.gif]