Greetings everyone, just joined and in need of some help. I work at a chrysler/dodge dealer as a service advisor and this past summer I went with my soon to be fater in law to for him to purchase a 1998 Ram Van 3.9L 3speed work truck. Truck is super clean and was a former Verizon work truck. He asked for my opinion and I checked it out everything looked good. Since about September the van stalls when slowing down to a red light or stop sign. Restarts fine but just shuts off. Then the torque converter locked up, had trans rebuilt at a place that we do business with here at the dealership. while it was there they also replaced the water pump cause it was super noisy. After the water pump he had no heat. We changed the heater core, thermostat, put another water pump on took the bypass valve off and probably flushed it 25 times with BG and other various cleaners. Still shuts off, so then we replaced the coil plugs wires rotor cap PCM. Still shuts off. All of this work was done by me and 2 other techs that have been here for 20+ years. They have no idea and after all, who likes to work on old junk? I somehow feel a little responsible cause i really thought it was a decent truck. I know I am new but does anyone have any idea what else I can look for/check? All wiring has been gone over at least 3 times. any help would be much appreciated. Thanks!!!!! scoops

 

It's too bad you didn't ask before dumping all of that time and money into it. All you need to do is clean the IAC valve. I'm surprised the 20-year vets didn't consider the IAC valve. Here is how to clean it: https://dodgeforum.com/forum/dodge-r...n-the-iac.html

If cleaning it doesn't solve the problem then replace it.

 

What is wrong with this comment?

 

Going to try cleaning the IAC this weekend, best suggestion I have heard from anyone so far, appreciate it. The junk comment, I personally will work on anything, techs here just want gravy, they could care less about actually diagnosing a problem, which is a shame. I actually needed some help and everyone just threw up their arms and gave up.

 

Which is exactly why the gang you find here actually figures out what the problems are and then turns the wrenches themselves. Techs at the Dealership have become code readers/parts swappers and not very much more.

 

Cleaned the IAC and still stalling. I'm lost on what else it could be. I know these vans were known for stalling/PCM issues. No codes. Checked all wiring at least 5 times

 

TIme for me to guess:

NEW IAC.


Throttle position sensor??

 

Now time for the IAC "Finger Trick", I am also suprised the 20 plus year techs did not know this one.

From a post by member Stev a few years back:
Per the advise of another Dodge forum on the internet, a DCX service tech, to me to give the TB the finger. After that all the problems went away. Well, this is a finger treatment you give to the IAC with the engine running at idle. Placing your index finger over the air-inlet port to the IAC on the TB, carefully and slowly choke off the air going into the port until the engine nearly stalls out. I did this several times since the IAC was pulsating. At the last time, I totally choked off the IAC until the engine stalled. This made the IAC to draw all the way back within it’s sensor housing. (NOTE: this is done only with the IAC mounted on the TB.)

The next step is critical. Take the negative battery terminal off for 2 mins. DO NOT touch the key until the 2 mins have passed.!!!! Now, turn the key off and reconnect the negative battery cable. This resets not only the PCM, but the other sensors for the TB.

Now, the final step was to turn the key back on for 5 seconds prior to a full start crank over. The IAC when it had stalled the engine from running drew all the way back in travel. Upon restarting, and waiting for the five seconds, I heard two distinct cracking noises from the IAC in movement as it went into it's position. Did this fix a sticky IAC or what was the finger trick suppose to do???

At first, I thought the advice was a little ! BUT, with nothing to loose, I tried it. Not only did this wacky procedure work, but the engine behaves far better than when I had originally purchased it. It worked so well, that stomping on the pedal from a dead stop now lays a 15 foot streak of rubber on the street! The van NEVER did that before since I’ve owned it! I thought, what did this finger thing ?!?!?

 

Like I said, if cleaning doesn't solve it you might need to replace it with a new IAC valve.

 

I have been living with this issue for over a year. My ISC costs over100.00. The real problem is the PCM. Prices quotes from 500.00 to 1200.00.
30 day warranty.
Found a rebuilt for 180.00 delivered to the repair place in 3 days with 2 year warranty. The place is in Florida. If someone needs the exact location I'll look for the receipt. My van has run for over a year since replacement of the PCM.