I have a 1999 Ram 1500 V6 will not idle, I did full tune up rotar, cap, plug wires and plugs. The truck has 81,000 replaced the catalytic converter also, the check engine light came on. It runs great on the highway
but once I stop so does the engine. Any one have ideas what I should check now thanks for the help.

Check your TB sensors!! Your MAP sensor is on the front, the Throtle position sensor is on the drivers side, and the AIS motor is on the back!! I would check the little 1 inch valume hose on the MAP and the MAPs voltage first...then pull the AIS sensor out of the back of the TB. Get a can of carb cleaner and spray it down. gently wipe the crud off the sensor but be carefull not to push the plunger all the way down....but make sure it can move freely...then check the voltage on the TPS...let us know if any of this helps....

the other thing you can do is take it to autozone and have them tell you what code you are throwing seeing as how your engine light is on.

It looks like the IAC valve is not working the book I have tells me to pull out the valve turn the key on and the pin should retract. Is this correct? It also shows the voltage on terminal A and B of the connector but
I have voltage on A and C. It is a Haynes repair manual. It looks like this may be where the problem is
any thoughts.

I may have been calling it the wrong thing! Are you talking about the sensor on the back of the TB????

Yes in the very back the connector has 4 wires it had a
little shaft with a head on the end of the shaft that
looks like it seats into the tb.

yep, 2 names for the same thing :)

Check the voltage for the IAC motor first by connecting a volt meter th the purple/black wire (+) and the brown and white wire (-). there should be voltage there..if not there is a break in the circut.

the other thing to do is like you said pull the IAC motor out of the TB but leave the socket connected. Turn the key on (but dont start the engine) if the pin does not move turn the key off and take the IAC out and clean it with carb cleaner....dont push the plunger in your self though.

If the plunger moves when you turn the key.....keep looking....or have autozone run a OBD II scan for you (its free).

Good luck, I just had to do this over the summer....pritty easy fix if thats the cause....let us know!!

Dave, what did you find out??

My guess is oxygen sensor. Saw similar situation recently. If you can get a code we can all stop guessing and I can tell you exactly whats wrong and the steps to diag.</P>

Sorry guys had to go out of town yesterday, what I did find is that the IAC valve does not retract when out will
test for voltage today . The check engine light went out when I put the new catalytic converter on.
Will test this today and let you know thanks for all the help.

so the plunger didnt move at all?? If you have voltage going to the IAC then clean it and see if that helps...if there is no voltage....take it in :)

good luck!

The plunger did not move I did clean it same issue. What is the voltgage level that I should see?

there is no true range given...its just discribed as 'battery voltage' basicly if there is no reading of voltage you have a break in the line...a bad sensor..or a faulty PCM.....what will happen if you take it in some where they will have a scan tool that they can plug into the sensor its self to tell them if there is a problem there....these tests are just simple (and probably in acurrate) things to do to try and see a problem. Do you have an auto zone near you?? If so take a quick ride up there and have them figure out what code you are throwing...