Chrysler Repair: 3,3L minivan stalling when comes to a stop, oil dipstick, cam shaft


Question
Hi,

I sent a question before but have come a long way since...2001 Grand Caravan 3.3. flex fuel....The short story to date...leaving out quite a few details...
One morning I started the car and it stalled.
Smelt burnt electrical odor from around PCM. Car won't start...no starter action.
Rebuilt PCM installed and car starts and runs for 20 seconds and stalls.
Then back to original...nothing...no starter action
Reinsulate wiring from injector loom and cam shaft sensor and coil pack back to the main loom....tough job...
Got junkyard PCM and installed....Close numbers on junkyard unit...
Car started and ran but was not perfect....once in a while it felt like it wanted to stall in slow speed situations....but really quite drivable....Drove for a week and then stalled on son at stop light who could not start...It started perfectly a half hour later and many times since...
It gets 15mpg and having bought new I know it should get closer to 18 around town.

No codes.

Here is the question: Is it possible and even likely that a VIN programmed, "rebuilt" PCM could help in my case?

Also, I just have an obdcii scanner connected to laptop. Do professioanl scanners "see" a lot more details?

minor driveabily issue
no codes
decreased fuel mileage
stalling problem...(this may be a flooding problem related to the driveabily issue and if the son know who to "floor it" and crank the starter it may have come back right then and there...)

Thanks - Tom

Answer
Hi Tom,
My first thought is that the egr valve is sticking slightly ajar and when that happens, as you slow down to a stop, the engine will die and refuse to start because the mixture is too lean. Similarly it will not accelerate well when the valve should be tightly closed as well. The mpg will also suffer if the mixture is inappropriate when driving at a steady pace.
The egr valve is located between the oil dipstick and the windshield wiper fluid container and it has a round top with a vacuum hose attached to it. The body of the valve is positioned in small diameter exhaust pipe. Between the valve body and the round top there is a flange which conceals the valve stem. Find the stem and note that it has a circumferential slot into which you can insert the tip of a screwdriver and use that to move the stem back and forth. Spray some WD-40 on the stem where it enters the valve body and then move the stem back and forth, and check that the internal spring-action is closing the valve to a dead stop. Then see if that solves your problems.
A more sophisticated reader tell you a lot of the engine sensor readings and can be useful if you know what they should be. I doubt you need a newly programmed pcm. I do recall your earlier question and am glad to learn of your progress.
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