Mortis Tortis

I'm at a loss. My 98 chevy suburban 1500, 5.7 vortec V8 engine, 4WD now idles so high that if I take my foot off of the break it accelerates to 40-50 mph. Check engine light is on and computer gives an error code 0141 which is for a O2 after sensor, left bank, heater activation. Is this something that can cause a high idle or is it a red herring? 2 mechanics have worked on it, including the local chevy dealership, but no one can figure out why it idles so high. The idle control mechanism has been replaced twice. Any ideas out there? Could a faulty O2 after sensor cause a high idle problem? Mortis Tortis

mountainmanjoe

The dealer just gave up and said sorry "I don't know how to fix our cars. You're on your own."? And they didn't fix the CEL either? Wow.

Cusser

Hey - that's EXACTLY what the local GM dealer told me when they were unable to fix the sunroof on my 2005 Yukon !!! Well, actually they said "we have NO IDEA why it won't close". Pretty sad.

kevinkpk

O2 sensor won't cause this issue. Dealer should fix your problem. High idle, give more input as to what/when, and any corrective action.

Doug D

Yeah, an faulty O2 sensor won't be the cause of high idle. Sounds like a vacum leak. Check the vacum lines - especially the one leading to the brake booster.