Yeret
The Village Drunk
- Joined
- Oct 2, 2014
- Posts
- 943
- Reaction score
- 178
- Ram Year
- 1999
- Engine
- 5.9 Magnum
Engine's picked up a high-idle problem starting a couple weeks back. At initial startup, it's fine but after driving, when I shift into Park, the engine revs up and holds between 900-1,000 RPM. If I rev it a little bit, it settles back to ~650. So, today, I replaced the IAC thinking this was the problem. Started up the engine and it idled fine, so I let it warm up. Everything seemed fine so I revved it a little. And SOB, the engine stuck at 1,500 RPM for a few seconds and slowly settled to 1,000 RPM again! I know that I fiddled with the throttle body idle screw earlier this year and came up with a ridiculous but plausible theory of how my new headers may have rendered this adjustment obsolete, so I spent the next couple hours backing off the screw, revving the engine and putting the tranny in gear until it idled normally. As of now, I'm a few turns backed off the screw (back to where it originally was...I think) and it idles better overall but it still occasionally holds 1,000 RPM. I noticed that if I'm in the truck and rev the engine, it seems fine but it I go under the hood and directly actuate the throttle blades, especially if I hold it slightly open very briefly, it wants to idle high. WTF?
Gonna go for a drive tomorrow and see what happens. Maybe the ECU hasn't learned the new IAC yet? Christ, how the hell long does it take, LOL. Otherwise, I don't know what the hell to say. I had my scanner plugged in and the TPS showed the same reading when the engine was idling normally and when it was high-idling so I don't think the TB is entirely to blame.
Gonna go for a drive tomorrow and see what happens. Maybe the ECU hasn't learned the new IAC yet? Christ, how the hell long does it take, LOL. Otherwise, I don't know what the hell to say. I had my scanner plugged in and the TPS showed the same reading when the engine was idling normally and when it was high-idling so I don't think the TB is entirely to blame.