Notices
GM Engine & Exhaust Performance EFI | GEN I/GEN II/GEN III/GEN IV Engines |Small Block | Big Block |

Poor idle at start up... Any ideas?

Thread Tools
 
Search this Thread
 
Old 10-04-2004, 10:13 PM
  #1  
Teching In
Thread Starter
 
computernerd's Avatar
 
Join Date: Sep 2004
Location: River Ridge, LA
Posts: 8
Likes: 0
Received 0 Likes on 0 Posts
Default Poor idle at start up... Any ideas?

I just got a 2000 Tahoe about two weeks ago.
It's bone stock right down to the air filter.
It has 5.3L and only 46k miles on it.
My problem is: at startup it has a poor idle.
It only idles at 500rpm to begin with and the the poor idle it drops to 200rpm then catches itself and revs to 800rpm.
The problem seems to happen more at start up, but I have also noticed it at a red light.

I'm going to check the fuel filter this weekend. Any other ideas?
Old 10-04-2004, 10:31 PM
  #2  
TECH Addict
 
marc_w's Avatar
 
Join Date: Oct 2003
Location: Central, MA
Posts: 2,618
Likes: 0
Received 0 Likes on 0 Posts
Default

My first guess would be the throttle body... I'd probably pull it off and clean it out nice and good.

My truck does that when something is up with my IAC motor due to some poor tuning by me. I have a feeling your TB might be gunked up with carbon or other junk.
Old 10-04-2004, 11:08 PM
  #3  
blownerator
iTrader: (20)
 
BlownChevy's Avatar
 
Join Date: Mar 1986
Location: Chatsworth, CA
Posts: 18,745
Likes: 0
Received 7 Likes on 7 Posts
Default

Originally Posted by marc_w
My first guess would be the throttle body... I'd probably pull it off and clean it out nice and good.

My truck does that when something is up with my IAC motor due to some poor tuning by me. I have a feeling your TB might be gunked up with carbon or other junk.

Good advise...start with the TB and IAC valve.
Old 10-05-2004, 09:42 AM
  #4  
PT's Slowest Truck
iTrader: (19)
 
budhayes3's Avatar
 
Join Date: Apr 2004
Location: Hackensack, NJ
Posts: 17,863
Likes: 0
Received 2 Likes on 2 Posts
Default

Check the fuel pressure regulator also if you're experiencing this more after a hot soak. Pull the vacuum hose off of it and see if fuel is present, if so, it's ng.
Old 10-05-2004, 09:58 AM
  #5  
Teching In
Thread Starter
 
computernerd's Avatar
 
Join Date: Sep 2004
Location: River Ridge, LA
Posts: 8
Likes: 0
Received 0 Likes on 0 Posts
Default

Thanks for the input.
I will check the throttle body and the fpr.
Seems to happen in some for all the time, so I'm banking on it being the throttle body.
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
ARC
GMT 800 & Older GM General Discussion
57
02-21-2022 10:54 AM
Mossyoakglock
GMT 900 Trucks General Discussion
4
08-28-2015 12:49 PM
The_W
FUEL SYSTEMS
4
08-15-2015 08:07 AM
05GMC4.8
GMT 900 Trucks General Discussion
5
08-07-2015 09:55 PM
Mossyoakglock
GMT 900 Trucks General Discussion
0
07-17-2015 08:30 AM



Quick Reply: Poor idle at start up... Any ideas?



All times are GMT -5. The time now is 04:07 PM.