[Marza]

Hoping maybe someone can help. Here goes

First problem was with stalling at random times. Fuel pump stopped working one day and filter was plugged solid. Changed
About 2 weeks later started misfiring, checked coil. Sparking only on 4 cylinders. Changed
Kept stalling at random times again. Checked fuel pressure (Constant 48 psi) Changed idle motor.
Drove 2 weeks this time started hesitating and popping at random times (p0106) Checked plugs/wires and replaced
Made it 2 days, same thing. (p0106) MAP sensor changed
Went 8 hours before doing it yet again except p0401 EGR. Clear codes, runs fine. Tried to reproduce it, drove around for over an hour but couldnt. Drove 2 blocks to the store and it did it. Very random
I took a peek at the crank sensor wires just to see if they had a break rigth there at the sensor like most develop, but no luck.
In all the years working on these things i have never encountered this before
Only thing not checked was TPS
Any input would be much appreciated

 

[ImperialCrown]

Welcome to Allpar. Stalling at stops, but OK while driving down the road?
The stalling may have caused the MAP fault code (and not the other way around) when the vacuum dropped to 0 at the point of stall. The old MAP sensor itself may be OK.
I would be very concerned about what is inside the fuel tank if the filter was plugged solid. You may have been trying to blow through the fuel pressure regulator which you probably can't do. You want to address this first, if there is a problem. Remove the fuel pump assembly with a low tank of gas and get a fuel sample from the bottom of the tank or examine the bottom of the fuel pump reservoir for debris.
It may take awhile for P0401 to reappear. The EGR transducer and valve may be leaking exhaust into the intake manifold. Too much EGR at idle can cause a roughness/stall. For diagnosis, try temporarily removing and plugging the vacuum hose to the black round plastic transducer to see if the stalling goes away.
The TPS can act up without setting a fault code. Monitor the signal to the PCM. This can be watched inside the vehicle with an OBD II scan tool/good code reader or long wires to inside the vehicle to a DC voltmeter. At idle, the TPS signal should sit 'rock steady' at it's base idle voltage which should be around 0.67 volts. If it varies up and down without touching the gas, check the connections and harness and if nothing is found, replace the TPS.

 

[Marza]

The stalling stopped when i replaced the idle motor. I apologize for not specifying
No, filter was removed from vehicle before i blew through it. 3 lines on filter,one from the tank to filter, one returns to the tank, the other supplies the motor (which was blocked solid). Pump failed pressure test as expected after filter change.
I understand, TPS was my next step.Im just afraid im chasing a ghost with the codes switching with same issues causing it.
Now im told the engine light is coming on randomly but without any problems. "Drives like a champ"
Once i get a chance to recheck the stored code then check voltage and resistance at TPS aswell as egr ill post my findings
I dont get much time with the van, its a daily driver
Thank you very much

 

[Marza]

Got it. Took a second look at the crank sensor. I gave a tiny tug and a wire came out and wire coating was melted.
I didnt do more than examine it by sight the first time
PCM was losing TDC randomly is my guess
Runs great now, lots of power and steady idle
Talked to previous mechanic and was told egr has been a recurring thing for years. Owner not interested if its not effecting drivibility
Thanks for your input