1998 Blazer revs at Idle - S-10 Forum
 
LinkBack Thread Tools
post #1 of 14 Old 03-28-2005, 12:27 PM Thread Starter
Registered Users
 
Join Date: Oct 2003
Posts: 7

User is: steve_blazer is offline
1998 Blazer revs at Idle

Blazer is randomly reving at stop signs while in drive and also while in park. Ideas?


Steve 98 Blazer
steve_blazer is offline  
Sponsored Links
Advertisement
 
post #2 of 14 Old 03-28-2005, 01:59 PM
ZR2 member
 
Scott01's Avatar
 
Join Date: Mar 2002
Location: Northeast Ky
Age: 44
Posts: 1,903

User is: Scott01 is offline
Re: 1998 Blazer revs at Idle

Dirty injectors
Weak pump
Clogged filter
Scott01 is offline  
post #3 of 14 Old 03-29-2005, 04:09 PM
Registered User
 
Blazerboy's Avatar
 
Join Date: Feb 2003
Age: 44
Posts: 81

User is: Blazerboy is offline
Re: 1998 Blazer revs at Idle

Messed with the throttle body or anything lately?
Blazerboy is offline  
post #4 of 14 Old 03-31-2005, 05:35 PM Thread Starter
Registered Users
 
Join Date: Oct 2003
Posts: 7

User is: steve_blazer is offline
Re: 1998 Blazer revs at Idle

No changes to throttle body. I have had suggestions that IAC may need cleaning. Also, had one person say that AC low on freon caused their blazer to rev every 5-10 seconds. Thanks for help.

Steve 98 Blazer
steve_blazer is offline  
post #5 of 14 Old 04-01-2005, 11:28 AM
Registered User
 
Blazerboy's Avatar
 
Join Date: Feb 2003
Age: 44
Posts: 81

User is: Blazerboy is offline
Re: 1998 Blazer revs at Idle

If the A/C is off at the time, it shouldn't cause it to rev.
Is the idle just coming up when you stop or is it surging up and down, up and down? I agree if the IAC is dirty it could cause a surging idle.
Blazerboy is offline  
post #6 of 14 Old 04-01-2005, 11:36 AM Thread Starter
Registered Users
 
Join Date: Oct 2003
Posts: 7

User is: steve_blazer is offline
Re: 1998 Blazer revs at Idle

Yes, it is as you describe. It surges up and down every 5 or 10 seconds while stopped. It hasn't been noticeable while driving. My son is driving the vehicle, so I won't see it until the weekend. The AC idea made some sense as it was very poor cooling last fall. Also, doesn't the AC get involved in some other air flow settings which might be in use now? I was planning on pulling the AC fuse first and then seeing about getting at the IAC. Would you suggest replacing the IAC or is a good cleaner a good choice?

Steve 98 Blazer
steve_blazer is offline  
post #7 of 14 Old 04-06-2005, 10:05 AM
Registered User
 
Blazerboy's Avatar
 
Join Date: Feb 2003
Age: 44
Posts: 81

User is: Blazerboy is offline
Re: 1998 Blazer revs at Idle

The A/c compressor kicks on whenever you're in A/C or defrost. So yes defrost setting will engage the compressor and may drag the motor down. Pull the IAC valve and clean it out real good with a carb cleaner, and while you're at it clean out the bore in the throttle body where it sets and see if that helps any. Also check for any vacuum leaks as well.
Blazerboy is offline  
post #8 of 14 Old 04-14-2005, 01:07 PM Thread Starter
Registered Users
 
Join Date: Oct 2003
Posts: 7

User is: steve_blazer is offline
Re: 1998 Blazer revs at Idle

Thanks for help and advice. The problem is the AC. Not sure yet what is wrong with AC, could be low coolant, I suppose. Determined it was the AC by pulling the 10 amp fuse for the AC. Problem immediately went away and didn't return again until fuse was plugged back in. The air setting was on defrost and that was causing the AC to try to engage.

Visually, it looks like the AC clutch is engaging every few seconds and then kicking out again. Little to no cool air is coming out. Any thoughts on the AC? Imagine I will need to have that serviced, but it would be good to know if you think it is coolant, if they suggest something more drastic with the AC.

Blazer is back at college again, so I won't see it for a while. Thanks again.

Steve 98 Blazer
steve_blazer is offline  
post #9 of 14 Old 04-15-2005, 03:58 PM
Registered User
 
Join Date: Nov 2002
Location: Houston, TX
Posts: 193

User is: Skinny is offline
Re: 1998 Blazer revs at Idle

Probably just low on freon. You can get a do-it-yourself kit at Wal-Mart or any auto parts store to recharge your system yourself. Be sure to get freon with stop-leak in it. You should be able to get all this for about $20. The directions will be easy to follow. If this doesn't work, then you should take it to a mechanic to have it looked at, but not before trying to remedy it yourself.
Skinny is offline  
post #10 of 14 Old 04-29-2005, 10:28 PM
Registered User
 
Vsandme's Avatar
 
Join Date: Feb 2004
Age: 29
Posts: 318

User is: Vsandme is offline
Send a message via AIM to Vsandme
Re: 1998 Blazer revs at Idle

Same problem here, ended up cleaning the mafs and it stoped, but mine did it when a/c was off so different case i guess
Vsandme is offline  
post #11 of 14 Old 07-08-2005, 02:45 AM
Registered User
 
coolal's Avatar
 
Join Date: Jun 2004
Location: Central Florida
Age: 36
Posts: 11

User is: coolal is offline
Re: 1998 Blazer revs at Idle

Quote:
Originally Posted by Vsandme
Same problem here, ended up cleaning the mafs and it stoped, but mine did it when a/c was off so different case i guess
mine does the exact same thing with air off, Vsandme what is mafs where are they i have a 95 blazer and its driving me nuts
coolal is offline  
post #12 of 14 Old 07-13-2005, 12:12 PM
Registered User
 
Vsandme's Avatar
 
Join Date: Feb 2004
Age: 29
Posts: 318

User is: Vsandme is offline
Send a message via AIM to Vsandme
Re: 1998 Blazer revs at Idle

Blazerboy, 98 blazer isnt tbi, csfi

I miss my jimmy, Plan on a Gen 1 longbed s10 project soon, till then im ridin that full size
Vsandme is offline  
post #13 of 14 Old 07-13-2005, 12:34 PM
ZR2 member
 
Scott01's Avatar
 
Join Date: Mar 2002
Location: Northeast Ky
Age: 44
Posts: 1,903

User is: Scott01 is offline
Re: 1998 Blazer revs at Idle

Quote:
Originally Posted by Vsandme
Blazerboy, 98 blazer isnt tbi, csfi
But they have a throttle body on them.
Scott01 is offline  
post #14 of 14 Old 07-13-2005, 04:53 PM
Registered User
 
skinnyg's Avatar
 
Join Date: Jun 2005
Location: MD
Age: 36
Posts: 3,135

User is: skinnyg is offline
Send a message via AIM to skinnyg Send a message via MSN to skinnyg Send a message via Yahoo to skinnyg
Re: 1998 Blazer revs at Idle

I CANT BELEIVE nobody mentioned egr valve
skinnyg is offline  
Sponsored Links
Advertisement
 
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the S-10 Forum forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address.


Email Address:
OR

Log-in









Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.



Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page



Posting Rules  
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome