The 1947 - Present Chevrolet & GMC Truck Message Board Network







Register or Log In To remove these advertisements.

Go Back   The 1947 - Present Chevrolet & GMC Truck Message Board Network > 47 - Current classic GM Trucks > The 1973 - 1987 Chevrolet & GMC Squarebody Pickups Message Board

Web 67-72chevytrucks.com


Reply
 
Thread Tools Display Modes
Old 05-09-2009, 08:01 PM   #1
keg
Registered User
 
Join Date: Jun 2008
Location: Snohomish Wa
Posts: 32
TBI help

A couple of months ago I had some problems with my 87 pick up. I rebuilt the throttle body and changed a couple of sensors. It runs OK now except the accelerator pedal seems stiff almost like it is sticking. It makes it very difficult to start out smoothly from a dead stop. Is this something caused by the TBI? Somethig I messed up or and adjustment? It is a 350
keg is offline   Reply With Quote
Old 05-09-2009, 08:45 PM   #2
arkracing
Weekend Warrior
 
Join Date: Oct 2004
Location: CT
Posts: 1,787
Re: TBI help

I'm curious as well. My buddy recently purchased an '87 TBI truck and the gas pedal/throttle is very stiff. Anybody else run into this problem or know what causes it?
__________________
-'07 GMC Sierra K2500HD
-'66 C10 Suburban
-'68/'71 K20 Service Bed Project
-'69 Chevy C30 Mason Dump

-'33Ford P/U 396ChevyPowered

Last edited by arkracing; 05-09-2009 at 08:45 PM.
arkracing is offline   Reply With Quote
Old 05-10-2009, 08:13 AM   #3
James McClure
One shot, one kill.
 
Join Date: Dec 2007
Location: Saratoga Springs NY
Posts: 859
Re: TBI help

I was a Chevy mechanic and we had problems with all the injection throttle bodies getting sticky after a while. It's a buildup of stuff on the back of the throttle plates and in the bore. Remove the throttlebody, clean the plate and bore with the throttle wide open. Also clean the shaft bore by spraying the shaft and moving the throttle. Blow dry and test by letting the throttle slam shut and then try to open it again. If it still sticks, look for shiney spots in the bore where the plate hits and clean them up with 400 paper. jim
__________________
1984 K20 350M engine with 465,000 miles. Well, it's finally done!! Almost 2 years of work, but it was really worth the effort. Little stuff left to do is mount winch, wet sand & buff out and build belly pan\running boards. Body work takes lots and LOTS of beer!!!! God, Guts and Guns made America and God, Guts and Guns will preserve it! The worst thing you could do is get into my sights, but that don't matter, you'll never know it, cause you'll never hear the shotJim or Paladin whichever you choose.
James McClure is offline   Reply With Quote
Old 05-10-2009, 11:19 PM   #4
75gmc454
Registered User
 
75gmc454's Avatar
 
Join Date: Oct 2006
Location: MS
Posts: 479
Re: TBI help

I have owned an 88, 90, 93, 95 with all tbi injection. The 88 and the 90 eventually got hard to push the accelerator. I am nearly 100% sure it is ONLY the cable. On both of the trucks I had to replace the cable and it fixed the problem.

It gets worn on the inside and it just seizes up. You cannot oil it, replace it!! I guarantee it will be so easy to push you will think you are in a different truck.

Easy way to check is to unhook the accelerator cable and work the tbi with your hand. It should work easily and freely. If it does, it is the accelerator cable.
75gmc454 is offline   Reply With Quote
Old 05-18-2009, 01:40 PM   #5
keg
Registered User
 
Join Date: Jun 2008
Location: Snohomish Wa
Posts: 32
Re: TBI help

Just to follow up. The old cable seemed to work OK, but I replaced it with a new cable anyway and it fixed the problem. Works great now.
keg is offline   Reply With Quote
Old 05-18-2009, 01:43 PM   #6
Tony_SS
Registered User
 
Tony_SS's Avatar
 
Join Date: Dec 2008
Location: Washington, MO
Posts: 643
Re: TBI help

Great to hear.. My pedal is hard as a rock.. I'll replace the cable.
Tony_SS is offline   Reply With Quote
Old 05-18-2009, 03:07 PM   #7
bigarmzz
Registered User
 
bigarmzz's Avatar
 
Join Date: Sep 2004
Location: Elkins, West Virginia
Posts: 2,542
Re: TBI help

every throttle body truck i've owned, (4), has had a stiff pedal....i always end up putting on a new cable and it has always seemed to do the trick
__________________
1987 350 TBI lowered 5/7
bigarmzz is offline   Reply With Quote
Old 05-18-2009, 08:48 PM   #8
arkracing
Weekend Warrior
 
Join Date: Oct 2004
Location: CT
Posts: 1,787
Re: TBI help

I'll try that, I disconnected the cable and it seemed ok - pushing it back and forth by hand, but I guess that isn't a good way to test.
__________________
-'07 GMC Sierra K2500HD
-'66 C10 Suburban
-'68/'71 K20 Service Bed Project
-'69 Chevy C30 Mason Dump

-'33Ford P/U 396ChevyPowered
arkracing is offline   Reply With Quote
Reply

Bookmarks


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

Forum Jump


All times are GMT -4. The time now is 09:32 PM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Copyright 1997-2022 67-72chevytrucks.com