High idle/Won’t start
Thread Starter
7th Gear
Joined: Oct 2025
Posts: 7
Likes: 0
From: Fulton, MO
High idle/Won’t start
2000 with 15,000 miles and no previous issues. On cold start immediately idled to 2500+ rpm, continuously. I shut it down and then it turns over but won’t start. No codes. Any ideas what it could be?
Tech Contributor
Joined: Jan 2007
Posts: 19,397
Likes: 1,137
From: Dyer, IN
How did you check for codes? Will you be doing the repairs yourself? Do you have a test light, DMM, and a fuel pressure gauge to connect at the fuel rail?
Thread Starter
7th Gear
Joined: Oct 2025
Posts: 7
Likes: 0
From: Fulton, MO
I checked codes DIC codes by holding down “options” then cycling through that process. I’m not going to do the work myself, I was just hoping to have some idea what the problem might be before taking it to a shop. Thanks!
Melting Slicks
Joined: Sep 2008
Posts: 3,131
Likes: 799
From: Espanola New Mexico
From the original high idle problem I am guessing that there is some problem with either the PCM and or the TAC module. Both modules reside under the battery tray and are accessible by removing passenger tire and unbolting a cover. The car not starting is either due to no spark or no fuel.
Moderator, Tech Contributor
Joined: Sep 2013
Posts: 15,498
Likes: 3,999
From: Cape Coral, Florida
If no Tach movement during cranking it may be a faulty crank sensor...you will not have spark or injector pulse...you can try spraying an alternate fuel like Brake Kleen into the engine and if it starts momentarily you have a fuel delivery issue.
Burning Brakes
Joined: Dec 2022
Posts: 1,025
Likes: 888
From: Nappytown MD
High idle could be caused by a vacuum leak or possibly a MAF issue. My MAF failed and threw a code "MAF high voltage out of range" or something to that effect. Didn't trip CEL but did drop a code and caused high idle. I was having a heck of a time getting my O2's to set for emission test and that is how I found the issue trouble shooting the O2's. Not saying this is related to the no start issue, just possible high idle causes.
