1998 Dodge Ram idle air control problem

KJA1965

MEMBER
1998 DODGE RAM
V8
4WD
AUTOMATIC
13,000 MILES

1998 dodge ram 2500HD 4WD 5.9 gas v8
the idle air motor opens intermittently. First after idleing untill motor came up to temp the idle air motor would open and would start running rough then die.
that symptom has stopped ( I think ) after replacing both o2 sensors, tps, idle air motor, coolant temp sensor,
now it opens just going down the road at low throttle positions. Acceleration and power seem ok. But I can hear it open in non idle positions, should it do that?
i thought I should only open when idling, the air temp sensor is next am I chasing a ghost or a legit problem
computer code check only showed o2 sensor problems

1 Reply

SLAMMER

MEMBER
15 POSTS

Idle and when it senses a load or needs more air. Might take the TB (throttle body) off the intake and remove the IAC (Idle ai control) and clean the whole thing with good gumout/ valvoline synthetic carb cleaner. Make sure you check the IAC port they have a tendency to carbon up in the port. You can use a small brush, Q-tip, etc. To get in the port. GENTLY WIPE the PINTLE of the IAC! DO NOT TWIST OR PULL/PUSH IT YOU WILL DAMAGE IT. Clean the throttle blades too in and out. Might be a cheap fix. You can unbolt the IAC and leave it connected have someone turn the key to on BUT DON'T START IT! If you do the engine RPM may rev away! (Red Line) See if the pintle on the end retracts, thats a quick check to see if it is working mechanically wise. Make sure the engine is COLD while testing. It is basically a air by-pass hole, lets more air in when needed. I would do that before throwing anymore parts/money at it! It's cheap and it's a wasted Hour at best! IMHO (PS try ww. Dodgetalk. Com, 2nd generation rams, their good folks and it's FREE!)