I have a 96 Dakota with a 3.9 V6 that today started but won't idle. Once it is started as long as you keep giving it gas it will run but as soon as you let off it stalls. I need help ASAP as this is my only transportation.

 

EGR valve may be stuck open, if so it will not run. (Block it off)
Drop in fuel pressure. ( Should be 35psi with vacume line hooked up and 39psi without.)
Throttle body clogged. Take it off and hold it up to a light source. Can you see light between the body and the flappers or is there a slight amount of oil around the edges of the flappers. Look at the two tiny holes between the two main holes, make sure they are clean.
Idol speed motor not functioning properly.

When it does initially start, does it run normal or does it miss and run rough before it dies?

Do you know how to retrieve codes? Turn the ignition from off to run 3 times, leave it in the run position on the third time. Concentrate your attention to the check engine light. Have a pen and paper ready. Wait for the light to go out and then it will start flashing. It will blink in a sequence corresponding to #'s. It will flash once, pause, then flash twice. This means 12(start sequence code). There will be a brief pause then it will proceed to the next series of numbers. The last code is 55(it will flash 5 times, pause, then flash 5 times again). Write all the codes down on sequence and post them. There may not be any between 12 and 55, thats ok, and nott all codes will triger a check engine light either, so see what you have.

 

I lied, fuel pressure should be more like 45 to 50psi for a 96, sorry.

 

360DakotaPwr
The throttle body looks to be OK. No excess build up or anything. I have to check the EGR valve yet but when it starts as long as you give it enough gas to keep the RPMs at 700 or more it stays running but as soon as you let off the throttle it dies. No missing or roughness just no idle control. I also noticed the when you first start it the gas pedel doesn't move on it's own during the start as it used to do. Also there is another cable that comes off the throttle control ( pulls same direction as gas pedel cable ) and goes to a unit on the firewall. What is this? Please forgive my lack of knowledge but I come from the era of carborators and distributors with points! Thanks for any and all help.

Jack

 

We have a 1994 Dakota with the exact same problem, started fine, ran fine and then died when it was supposed to idle. After reading this and a few other threads we started with checking codes (none thrown) and then checking the battery. Once the battery terminal posts and the inside of the cables were cleaned and tightened it fixed the problem.

 

So I see this thread is old, but it can still pop up on the search so for what it's worth here's my 2 cents:

Had a very similar issue with my 96, was running fine and one day it died while idling at a stop light. Wouldn't start again unless I gave it some gas while turning the key. Again it would stall as soon as I let it idle in gear ( no its not a stick. ). Got it home and gave the throttle body some TLC, cleaned it all up including the IAC and replaced the gaskets between the TB and intake and the air box and TB. Seems to be doing fine now. She's a good truck.

 

So the truck idles normally until warm. Code was a P0141 for upstream O2S. Sensor replaced and still dies.

 

Remove the AIS motor (Automatic Idle Speed ) and clean. If it looks very dirty, replace it. When install it back on to the throttle body, be sure there is an O-ring on the motor or you have a vacuum leak.