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 1988 - 1998 Chevy & GMC Pickups Message Board

Web 67-72chevytrucks.com


Reply
 
Thread Tools Display Modes
Old 10-02-2017, 06:33 PM   #1
Puke160
Registered User
 
Join Date: Nov 2014
Location: Paola, ks
Posts: 33
2000 k2500 backfire though the exhaust

My 2000 k2500 with the 5.7 and 4l80E backfire though the exhaust at all idle..
About 3000 mile ago i gave it a full tune up new cap and rotor, coil, plugs, wires, air filter, and cleaned the throttle body. And the truck ran great after that.

Around 400 miles ago i got what i thought was a bad tank of fuel. 10 miles after i filled up it started backfiring. I tried to just run though it, but 2 day ago my fuel pump went out so i drained the whole tank and started with all fresh fuel.

When i got it all put together it is still backfiring like crazy. I have a good stong spark on all my plugs. I really dont want to just randomly start replacing stuff but i am lost.
__________________
1949 Chevy C3100
1979 GMC K25
1982 Chevy C20
2000 Chevy K2500
2002 Pontiac Trans Am
Puke160 is offline   Reply With Quote
Old 10-04-2017, 10:31 PM   #2
Puke160
Registered User
 
Join Date: Nov 2014
Location: Paola, ks
Posts: 33
Re: 2000 k2500 backfire though the exhaust

I just changed the timing chain. And the old one was about an 1/4"longer and a littebit loose but not real bad. But it still backfires the same.

I also checked the valve train. Set the rocker and all the valves have full range of motion and none of them were sticking or binding.

So i guess im down to replacing sensors. Or the fuel injectors. Has anyone had issues with the injectors sticking open? That would explain the backfire in the exaust, the lost of power and the 6 miles to the gallon.
__________________
1949 Chevy C3100
1979 GMC K25
1982 Chevy C20
2000 Chevy K2500
2002 Pontiac Trans Am
Puke160 is offline   Reply With Quote
Old 10-05-2017, 12:36 PM   #3
Kudzupatch
Registered User
 
Kudzupatch's Avatar
 
Join Date: Apr 2013
Location: GUNTERSVILLE
Posts: 398
Re: 2000 k2500 backfire though the exhaust

Have you checked for error codes?

Injectors are more likely to clog and cause it to run lean, not rich.

I would run a compression check before I started randomly replacing sensors. Replacement parts these days are just as liable to be bad as good. You could make it harder to find that problem. I am betting this is a mechanical issue, not electronic.
Kudzupatch is offline   Reply With Quote
Old 10-09-2017, 11:23 AM   #4
Puke160
Registered User
 
Join Date: Nov 2014
Location: Paola, ks
Posts: 33
Re: 2000 k2500 backfire though the exhaust

The truck does not have any codes.

And I have not done a compression test yet my gauge got dropped and stop work.
__________________
1949 Chevy C3100
1979 GMC K25
1982 Chevy C20
2000 Chevy K2500
2002 Pontiac Trans Am
Puke160 is offline   Reply With Quote
Reply

Bookmarks

Thread Tools
Display Modes

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 12:49 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
Copyright 1997-2013 67-72chevytrucks.com