My son has 01 1500 with problem. When started in morning, it will turn over and run for about 3 minuets, then it bogs down and ideling rough and wanting to stall. when doing this, you hear a loud sucking of air coming from cold air intake i presume. does this for about 3 more minuets, calms down then runs fine until next morning when starting, only does it on cold start. We have replace map sensor and new iac. what else could be the problem? Mechanic is stumped.

it is 2001 dodge ram 1500 quad
5.9 engine

any help would be greatly appreciated

thanks

 

The IAC might be a defect. And did the throttle body bore where the IAC installs into get cleaned? Also test the TPS.

 

IIRC, someone described a similar problem, and it was the front 02 Sensor. Seems it was only occurring as the engine was warming up, before it went closed loop.

 

Bravo, I do believe you are correct sir. I also read that thread, and there was no cel either.

 

I'm not necessarily disagreeing with you as I do not recall that thread, but I don't see how this would be possible.

Closed loop is where the truck listens to the O2 sensor. Before that, during "warm up" (open loop), it ignores the sensor. Why would changing the sensor affect the warm up period when it doesn't listen to the sensor?

 

he said it runs ok for about 3 minutes, then runs rough.
could it warm up enough in 3 minutes to get to closed loop ?

 

Mine does it in 4-6 minutes. Timed it back when I had the Superchips issue, where it would hesitate/stumble in open loop but not in closed loop.

 

so everybody is thinking 02 sensor. even without throwing any codes? even has my mechanic stumped

 

i think its safe to say everyone on here is a mechanic. some probably know more about their ram than any mechanic does...if its a cheap part and its suggested, i would try it.

 

so today he starts truck and goes to take off and you can hear it bogging down and when trying to give it gas hear a popping noise.