[SOLVED] Trailblazer stalls at idle when defrost or A/C turns on - Chevy TrailBlazer, TrailBlazer SS and GMC Envoy Forum



Welcome Enthusiast! If you already own a Chevy TrailBlazer or GMC Envoy or perhaps thinking of purchasing such a vehicle, then you have come to the best TrailBlazer and Envoy site on the net! Rainier, Bravada, Ascender, and 9-7x owners welcome too!

You are currently viewing our site as a guest which gives you limited access to view most discussions and access our other features. By joining our free community you will have access to search and post topics, communicate privately with other members, respond to polls, upload content, and access many other special features. Registration is fast, simple and absolutely free so please, join our community today!

If you have any problems with the registration process or your account login, please contact contact us.
Join Today!
Go Back   Chevy TrailBlazer, TrailBlazer SS and GMC Envoy Forum > 2002 - 2009 TrailBlazer/Envoy Tech > 02-09 Vortec 4.2L I-6 Engine and Drivetrain > OEM Issues

OEM Issues Original Equipment Repairs and/or Problems

TrailVoy.com is the premier GMC Envoy Forum on the internet. Registered Users do not see the above ads.
Reply
 
Thread Tools
  #1  
Old 01-21-2010, 11:54 AM
04TBStephanie's Avatar
04TBStephanie 04TBStephanie is offline
Junior Member
 
2007 Chevy TrailBlazer SS (LT)
Summit White 6.0L LS2 V8 2WD
Join Date: Jan 2010
Location: Aiken, SC
Posts: 2
Trailblazer stalls at idle when defrost or A/C turns on

Hi, everyone, this is my first time posting on here! Ok I just got an 04 TB with 72,000 miles on it. When we first got it the thermostat went out within a week but it was replaced and good now! Now when I turn my car on and let it sit its just fine, but when i turn the defrost or A/c or just heat on at idle my car dies. Thr RPMs just drop out. So I took it back to the dealership and their mechanic said he cleaned some hose and recalibrated some blades. When I got back in my TB and started it up and turned on the defrost again it still dropped down into the 500's but kicked back up but it is still dropping into the 500's alot. I called a real chevy dealership and they told me that whatever this "mechanic" did sound like BS! I'm thinking its my fan clutch because my husband has an 05 TB with 73000 miles on it and it was doing the same thing and this chevy dealership replaced the fan clutch and now it has no problems what so ever. Both of our TB's started doing the same thing around the 72000 mile marker. Is this typical? What do you guys think??? What do you think the "mechanic" really did???? Any help would be greatly appreciated.
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
  #2  
Old 01-21-2010, 12:14 PM
bvad02's Avatar
bvad02 bvad02 is offline
Junior Member
 
2002 Olds Bravada
Pewter Metallic 4.2L I6 AWD
Join Date: Feb 2006
Location: Windsor, Ontario
Posts: 50
it is most likely just a dirty throttle body. follow this how to and should clear up your problem.
http://forums.trailvoy.com/articles....ticle&artid=91
Reply With Quote Quick reply to this message
  #3  
Old 01-21-2010, 06:30 PM
WOOLUF1952 WOOLUF1952 is offline
No longer with us
 
2003 GMC Envoy SLT
Magnetic Red Metallic 4.2L I6 4X4
Join Date: Jul 2008
Location: Milwaukee, WI
Posts: 7,190
I think the "mechanic" did nothing. The dirty throttle body is 99.999% the problem. Many forum members clean their t-body every 30k miles. Its is an easy and cheap fix.
Reply With Quote Quick reply to this message
  #4  
Old 01-21-2010, 06:50 PM
0202-TB 0202-TB is offline
Junior Member
 
2002 Chevy TrailBlazer LT
Steel Gray Metallic 4.2L I6 4X4
Join Date: Sep 2009
Location: St. Augustine Fl.
Posts: 25
The throttle body cleaning should be at the top of your list of things todo..... I changed my battery, then it idled fine but when I turned on the AC, RPM would drop to 200 compressor shut off. it would cycle rapidly 2 seconds max. RPM 600--200--600. sometimes would stall. I cleaned the throttle body and it completely fixed it all. I was totally amazed. The best $3.00 I ever spent.
Long story short, DO IT...
Steve

PS, welcome!!
Reply With Quote Quick reply to this message
  #5  
Old 03-17-2010, 06:15 PM
04TBStephanie's Avatar
04TBStephanie 04TBStephanie is offline
Junior Member
 
2007 Chevy TrailBlazer SS (LT)
Summit White 6.0L LS2 V8 2WD
Join Date: Jan 2010
Location: Aiken, SC
Posts: 2
Thanks so much it absolutely was the throttle body, i made the "mechanic" do it. lol
Reply With Quote Quick reply to this message
  #6  
Old 12-12-2010, 09:16 PM
yannyfreak yannyfreak is offline
Junior Member
 
2004 Chevy TrailBlazer LT
Silver Green Metallic 4.2L I6 4X4
Join Date: Aug 2010
Location: Reading, pa
Posts: 10
stall when a/c clutch engages

Hi all, just read this older post trying to troubleshoot my problem and something grabbed my attention. I just replaced the thermostat a couple of days ago so I had the battery disconnected for several hours. Seems like this post is refering to a stalling problem after a thermostat replacement as well. Just a coincidence??? My car ran flawlessly until removing power to do a thermostat job. Could something be glitched in the tuning from a computor reset or something?? My symptoms are the exact same stalling as explained here. Just a thought, any input would be greatly appreciated. (I'm going to clean the TB of course, its due anyway)
Thanks, Jesse
Reply With Quote Quick reply to this message
  #7  
Old 12-12-2010, 09:33 PM
RayVoy's Avatar
RayVoy RayVoy is offline
TrailVoy Guru
 
2009 Chevy Avalanche LTZ
Black 5.3L V8 4X4
Join Date: Jul 2006
Location: Atlantic Canada
Posts: 6,431
Dozens and dozens of threads on stalling problems caused by the dirty throttle body.

Your problem falls under this heading as well......................yes it does.

As the tb gets dirty, the PCM adjusts the fuel mixture to allow the engine to idle smoothly (based upon info provided by the O2 and other sensors).

When you disconnect the battery..... for any reason..... the "adjustments" (discussed above) are erased from the PCM memory; and when the truck is started, the factory tune is in the memory.

The engine now has a dirty tb and a tune for a clean tb, the result is an engine that idles rough and stalls under load.

Give it some time, and it will re-adjust it'self, but the best fix is to clean the tb.
__________________
Ray
Reply With Quote Quick reply to this message
  #8  
Old 12-13-2010, 01:11 AM
yannyfreak yannyfreak is offline
Junior Member
 
2004 Chevy TrailBlazer LT
Silver Green Metallic 4.2L I6 4X4
Join Date: Aug 2010
Location: Reading, pa
Posts: 10
Thanks Ray. That makes perfect sense. Going to clean it right now
Reply With Quote Quick reply to this message
  #9  
Old 12-13-2010, 01:39 AM
WOOLUF1952 WOOLUF1952 is offline
No longer with us
 
2003 GMC Envoy SLT
Magnetic Red Metallic 4.2L I6 4X4
Join Date: Jul 2008
Location: Milwaukee, WI
Posts: 7,190
Just make sure you use a throttle body safe cleaner.
__________________
[COLOR=red]Oh, what a tangled web we weave, when first we practice to deceive. :([/COLOR]
Reply With Quote Quick reply to this message
  #10  
Old 12-13-2010, 02:18 AM
yannyfreak yannyfreak is offline
Junior Member
 
2004 Chevy TrailBlazer LT
Silver Green Metallic 4.2L I6 4X4
Join Date: Aug 2010
Location: Reading, pa
Posts: 10
Throttle body cleaned. Problem is gone. Thanks guys!
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
Reply

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the Chevy TrailBlazer, TrailBlazer SS and GMC Envoy Forum forums, you must first register.

Please enter your desired user name, your email address and other required details in the form below.
(Only letters, numbers, dashes and underscores are permitted for user names)
The user name that you choose is permanent and can never be changed.
User Name:
If you do not want to register, fill this field only and the name will be used as user name for your post.
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 for yourself.
Email Address:

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.




Currently Active Users Viewing This Thread: 4 (0 members and 4 guests)
 
Thread Tools

Posting Rules
You may post new threads
You may 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

Forum Jump


» Sponsors

Advertising Info

All times are GMT -4. The time now is 01:25 PM.


Chevy TrailBlazer and GMC Envoy Enthusiasts - Copyright 2004 - 2009 All Rights Reserved.
All trademarks referenced herein are property of their respective owners.
RSS Feed