Heyo!
I've been having one hell of a time tracking down an issue that's preventing my Jeep from running below 1100rpm. The jeep in question is a 1995 Automatic XJ with the 4.0L.
Main issue is how high the idle is. It also has a ton of vibrations, feels almost jerky in gear without my foot on the pedal, and consumes a shit ton of gas. Like 100 miles per tank. The idle won't go down below 1100rpm when warm, or in gear or with the AC on. It does gradually come down from about 2000rpm when cold. I overheated the hell out of the thing a month ago due to my mechanical fan failing while I was in traffic, but I hope it was unrelated.
Here's what I have already replaced:
Plugs, wires, rotor, cap, and coil.
Replaced the plugs again after the truck overheated.
The IAC and TPS.
Coolant temp sensor and thermostat.
Motor mounts were replaced with Rusty's rubber mounts (that wasn't fun)
Catalytic converter
Here's what I've done:
Cleaned the throttle body.
Checked all vacuum fittings and replaced cracked ones.
Sprayed the manifold with starter fluid for vacuum leaks.
Checked grounding voltage.
Checked fuel pressure (33psi at idle)
Checked manifold pressure (17in Hg at idle, but not a steady needle)
My experience and my research is telling me that I have a massive vacuum leak wasting air somewhere, but I also feel like the timing is off due to the unsteady needle. What could be causing my idle to be that high at all times? It's driving me crazy.
Thank you for all your help!
I've been having one hell of a time tracking down an issue that's preventing my Jeep from running below 1100rpm. The jeep in question is a 1995 Automatic XJ with the 4.0L.
Main issue is how high the idle is. It also has a ton of vibrations, feels almost jerky in gear without my foot on the pedal, and consumes a shit ton of gas. Like 100 miles per tank. The idle won't go down below 1100rpm when warm, or in gear or with the AC on. It does gradually come down from about 2000rpm when cold. I overheated the hell out of the thing a month ago due to my mechanical fan failing while I was in traffic, but I hope it was unrelated.
Here's what I have already replaced:
Plugs, wires, rotor, cap, and coil.
Replaced the plugs again after the truck overheated.
The IAC and TPS.
Coolant temp sensor and thermostat.
Motor mounts were replaced with Rusty's rubber mounts (that wasn't fun)
Catalytic converter
Here's what I've done:
Cleaned the throttle body.
Checked all vacuum fittings and replaced cracked ones.
Sprayed the manifold with starter fluid for vacuum leaks.
Checked grounding voltage.
Checked fuel pressure (33psi at idle)
Checked manifold pressure (17in Hg at idle, but not a steady needle)
My experience and my research is telling me that I have a massive vacuum leak wasting air somewhere, but I also feel like the timing is off due to the unsteady needle. What could be causing my idle to be that high at all times? It's driving me crazy.
Thank you for all your help!