Q: Low idle RPM.

asked by on December 02, 2017

When I start my 92 Jeep Wrangler it idles at about 1000rpm for about a minute and then it drops to around 300-400 rpms. I removed my throttle body and used throttle body cleaner and removed all the carbon build up in and around it. I then replaced my IAC valve with a brand new one. After hooking everything back up it idled around 800-900 rpm. After driving for about 10 min it started to bog down again to the 300-400 range. What else could be causing this low idle rpm?

My car has 117000 miles.
My car has a manual transmission.

Hey Scuba. Thanks for contacting us today. Most of the time, when the idle control valve has been replaced and throttle body cleaned, a low idle is typically caused by a small vacuum leak, restriction within the fuel injectors or perhaps damage to the throttle body itself. On a 92 Jeep, it’s likely that your issues are mechanical or caused by restricted fuel flow, or perhaps a clogged fuel filter. I’d recommend changing your fuel filter first, check for any vacuum leaks and try to clean the fuel injectors first to see if this resolves your issue.

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