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 09-12-2008, 05:32 PM   #1
Geno H
Registered User
 
Join Date: Aug 2008
Location: Raymond Kansas
Posts: 28
Truck backfires only when shut off?????

When I shut my truck off after it is at operating temprature it backfires one time very loudly like a CANNON. Any ideas? Is it the timing maybe? I havent check it but I did have to replace the muffler after I bought it. Upon further inspection of the old muffler it was sure enough blown out not rusted out or worn out but it was blown apart. Any help would be appreciated.


Geno H
__________________
1971 GMC 1/2 ton Project
1982 Chevy 3/4 ton Daily driver
1982 Chevy 1/2 ton SWB Big Project

Last edited by Geno H; 09-12-2008 at 05:34 PM.
Geno H is offline   Reply With Quote
Old 09-12-2008, 08:35 PM   #2
gchemist
BAD BOW-Silverado XST
 
gchemist's Avatar
 
Join Date: May 2000
Location: Senior Member from Austin, TX
Posts: 6,431
Re: Truck backfires only when shut off?????

Too much timing, a bad ground, a bad electrical connection and possibly too much idle.
__________________
Gerardo a.k.a. Mad Chemist
Silverado XST videos
gchemist is offline   Reply With Quote
Old 09-13-2008, 02:01 AM   #3
Geno H
Registered User
 
Join Date: Aug 2008
Location: Raymond Kansas
Posts: 28
Re: Truck backfires only when shut off?????

Thanks gchemist. I will check all of those things out.
__________________
1971 GMC 1/2 ton Project
1982 Chevy 3/4 ton Daily driver
1982 Chevy 1/2 ton SWB Big Project
Geno H is offline   Reply With Quote
Old 09-13-2008, 04:12 PM   #4
crawdadfox
Registered User
 
crawdadfox's Avatar
 
Join Date: Aug 2008
Location: New Orleans Louisiana.....a great place to visit but you wouldn't want to live here!!!
Posts: 883
Re: Truck backfires only when shut off?????

Are you feeding it red or white bean's?!! Just kiddin' i would say it's ignition and / or timing issue.
crawdadfox is offline   Reply With Quote
Old 09-14-2008, 11:40 AM   #5
raiders3581
Junior Member
 
raiders3581's Avatar
 
Join Date: Jun 2006
Location: pomona ca
Posts: 187
Re: Truck backfires only when shut off?????

I dont know maybe just me two cents , but does it put out black smoke when it starts? If so carb could be sticking a little dumping gas after shut down and since engine still hot enough to ignite fuel.. any way just a guess
__________________
67 short bed fleetside/1997 c1500 exteded cab/ 2004 accord/87 c10silverado 350 od tbi
raiders3581 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 10:33 PM.


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