Corvette C4 Forum 1984 through 1996

High Idle

  #1  
Old 08-09-2007, 01:19 AM
dpop24's Avatar
Thread Starter
Join Date: Sep 2006
Posts: 16
Default High Idle

My 91 recently started idling very high. It used to hang around 1000 RPM but just this past week it idles at 1500 when cold and between 2000-2500 after it warms up. I know this is too high, but is there an easy fix for a novice mechanic or do I need a pro to take a look? The manual says to hold it at 2000 RPMs for 2 minutes to clear the oxygen sensors. This was the first thing I tried and it didn't work.
 
  #2  
Old 08-09-2007, 12:50 PM
Join Date: Aug 2007
Location:
Posts: 173
Default RE: High Idle

we are goning to need more info to solve your problem, are there any codes(check engine light on) how many miles and when was the last tune up (plugs, opti cap, wires, air filter???) you need to check your timing also.
 
  #3  
Old 08-10-2007, 04:35 PM
Join Date: May 2006
Location:
Posts: 343
Default RE: High Idle

My '87 baby idles around 750, extremely smooth even at that low rpm

I heard this is normal[sm=icon_cheers.gif]
 
  #4  
Old 08-11-2007, 12:04 AM
dpop24's Avatar
Thread Starter
Join Date: Sep 2006
Posts: 16
Default RE: High Idle

Hey guys, thanks for the input. There are no codes except the annoying "sys" that has flashed ever since I put in a new aftermarket stereo.

I have about 134,000 miles and haven't done a tune up since I bought it last year at 130K. I'm guessing you guys are going to tell me that I need to give her a tune up.....

I will do that in the next week or so.... what is an "opti cap"?
 
  #5  
Old 08-11-2007, 06:39 AM
mech259's Avatar
Super Moderator
Join Date: Jan 2006
Location: Lumberton, Texas
Posts: 1,858
Default RE: High Idle

Sounds like idle control motor. Only way to be sure is to see what IAC counts are on a scan tool. If you replace idle control, be sure and disconnect battery for a couple of minutes to reset idle. Then drive it to let it relearn idle.
 
  #6  
Old 08-18-2007, 10:53 PM
Join Date: Aug 2007
Location:
Posts: 173
Default RE: High Idle

from what you saying it sounds like you need to take it to a reputable mech. and have him take a look at it(but buying parts to an un-diag. problem is not the answer)unless your comfy doing all of the above your self^^^
 
  #7  
Old 08-19-2007, 07:43 PM
Join Date: Aug 2007
Location:
Posts: 6
Default RE: High Idle

It's not a vette, but my year old focus started running high at idle. Took it and they told me the throttle plate and cable were loose. Perhaps this is also a possibility.
 
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
hereitis1967
Corvette C3 Forum
3
07-23-2012 07:33 PM
95trplblkandtan
Corvette C4 Forum
1
08-17-2008 10:33 PM
acedraven
Corvette C4 Forum
0
08-19-2007 11:00 PM
deltb
Corvette C6 Z06
28
11-24-2005 02:07 AM
HillSmith
Corvette C4 Forum
1
09-06-2005 11:53 PM


Thread Tools
Search this Thread
Quick Reply: High Idle



All times are GMT -5. The time now is 05:16 PM.