92 Ramcharger cold start

I have a 92 Ramcharger Canyon Sport plow truck that has a 5.9 fuelie that won't idle high when cold. If I keep me foot in it for a couple of minutes it will stay running, but if I start in and let of the gas it will die. What controls the idle at cold start?

isn't there a throttle position sensor?

water temp sensor for the pcm,must read correct temp& idle control valve or motor control idle speed,hot or cold.

I was looking at Rock Auto and it seems there are a few sensors that could cause this including the TPS. I am hoping someone would have been through this instead of just throwing parts at it. I am not at all familiar with Magnum engines. It runs find after it is warmed up.

you need a scanner to check water temp when cold,should be close to air temp.Start with that,it tells pcm what mixture&idle speed should be.Alos check air temp sensor,should be within 10-12 degrees of water temp when cold.

If the battery has died or recently replaced the first thing to do is clean the throttle body. The PCM will lose it's memory and start over as if it's new so it expects to see a certain amount of air flow at idle. It the throttle body is dirty it doesn't have that. Plus cleaning the throttle body is free.

Interesting. I will do just that!

Do those have an IAC motor on the throttle body? I've seen those get carboned up and stop working properly.

I had a similar problem with my Jeep 4.0 and it was the idle air motor. But getting it on a scanner to take a look at coolant temp certainly wouldn't hurt.

Could be the idle air control.

Helpful video here: Video

I have to give a mention to this Guy on Youtube, "Splelunkerd" that his 2nd Gen Ram videos are the best I've seen. He gives really clear instructions, lots of common sense style repair tips, and is smart as hell; worth subcribing or favoriting in your browser.

This Fellow takes the whole thing apart, but I just pulled mine out from the back, cleaned it with brake cleaner and was good as new.

Usually, Rhino if it's the IAC the idle will wander when it's cold. Hopefully, this is what your issue is (free fix )

This being a 92 360, it should not be a magnum, 92 360 was TBI yet, Look on the drivers side of the of the throttle body there is a motor with a plunger, have a helper turn key off and on, this should move the plunger in and out, if it does not, you most likely need a new idle control motor, these were bad failing .

You are right, here are pictures of the passenger side of the TBI. I will check the other side now. I thought it might be one of these sensors...

Well first things first, the MAP sensor is missing the vacuum hose.

The hose was going to the air cleaner, is it not supposed to go there?

Nope. Straight to manifold vacuum. The MAP sensor is basically an electronic vacuum gauge for the computer.

OK, I will check to see where the hose is supposed to come from, thanks!

i saw that also but it would be super rich if the map sensor vac line was off, which would make it run better cold. That might be open for a barometric reading?

Were you able to finish it?