High Idle, Dodge Ram 1500, 2001

Internal vacuum leak, intake manifold, Brake booster leaking, fuel pressure too high, sensor misread.

I was wondering if fuel pressure or leaky injector could cause it. I know the IAC is causing it, but something is telling it to do it. What i mean, i can hear the air bypassing around it and it is actuating because i can hear the pitch change as i am running. The other one was nasty dirty, i recently ran some bad gas in it, so i ran a can of injector cleaner through it, which was when this all started. So, what would cause a misread, that would cause the IAC to bypass air around the throttle?

Also, is it possible for the aluminum throttle body seat to be worn out enough to cause the high idle. It is better than it was, it was 1500+ and causing transmission to overheating due to bypassing oil through the torque converter while stopped in traffic, now its really slow to change and idles at 900-1200 in gear while stopped.

Most common are the ECT and the ACT sensors, they maybe telling the computer that the engine or air is super cold. A good scanner can show you live data of the sensors. Bad gas can cause catalyst and O2 sensor problems. Again a scanner can show you those.

A worn throttle body I’ll be obvious, just see if the shaft that goes through it will move up and down, do this with the engine running and if the rpm’s change a lot then you have a throttle body that need bushings. If the transmission is getting hotter than normal check the cooler, it could be restricted or even plugged.

Is the ACT sensor the one that senses the position of the flap on throttle body? Assuming that is the accelerator position sensor..

No that’s the TPS. The ACT is the Air Charge Temperature sensor. If you don’t have a scan tool rent one.