Offroad Trailblazers and Envoys

terrible fuel mileage

Something not working right?

by zeon_911 » Sun Dec 09, 2012 5:28 pm

ok so im getting roughly 10-13 mpg... a few monts back we had a flash flood and i was stuck in the middle of town. the water was so deep in parts of town peoples cars were swept away. i hydrolocked my engine... got towed home from a buddy and as soon as i got there i pulled the plugs and drained the oil, got the water out and chaned my oil a few times.. it runs just like it did before it hydrolocked but im happy to get 170 miles from a tank.. anyone have any ideas? getting real tired of it :cry:
zeon_911
Cruiser
 
Posts: 45
Joined: Sat Apr 28, 2012 1:47 pm
Location: TX, amarillo
Name: william mitchell
Vehicle Year: 2003
Vehicle: Chevrolet TrailBlazer
DriveTrain: 4WD w/ G80

by fishsticks » Sun Dec 09, 2012 5:37 pm

Clogged exhaust. Does the truck lack power?
11 Silverado LTZ - 6.2L/6l80, 2/3 drop, self tuned
85 Hilux - 3RZ, dual cases, caged, 40s, chromo everything
02 TrailBlazer LTZ - 35s, lockers, balls - Gone but not forgotten - Build
User avatar
fishsticks
Moderator
 
Posts: 4356
Joined: Thu Apr 01, 2010 11:30 pm
Location: WA, Vancouver
Name: Donny
Vehicle Year: Other
Vehicle: Other Vehicle
DriveTrain: 4WD w/ Aftermarket Locker
Rank: Extreme Offroader

by Moots1288 » Sun Dec 09, 2012 6:40 pm

10-13? That's normal for me
User avatar
Moots1288
Veteran
 
Posts: 1964
Joined: Fri Feb 24, 2012 8:42 pm
Location: Long island
Name: Moots
Vehicle Year: 2006
Vehicle: GMC Envoy
DriveTrain: 4WD
Rank: Offroad Rated

by v7guy » Sun Dec 09, 2012 7:05 pm

Throttle body cleaning, maybe the O2 is on its way out, plugs possibly.
I know a blown headgasket can ruin O2s, I would suspect that if any water made it down to it the same thing would apply.

Depending on your mods that doesn't sound too terrible. But you don't give us any info on what it was before or what you've done to the truck. Plus you don't have a build thread for us to refer to.
build thread

All things in moderation, including moderation.
Some people never go crazy... what truly horrible lives they must lead
User avatar
v7guy
Moderator
 
Posts: 3712
Joined: Wed Mar 09, 2011 10:17 pm
Location: NY, long island
Name: Jason
Vehicle Year: 2004
Vehicle: Chevrolet TrailBlazer
DriveTrain: 4WD
Rank: Offroad Rated

by bartonmd » Mon Dec 10, 2012 10:45 am

Likely the water ruined your O2 sensors, which are now reading lean, causing your engine to dump fuel to try and satisfy the (faulty) O2 sensors.

Mike
bartonmd
Moderator
 
Posts: 4469
Joined: Wed Sep 09, 2009 9:35 am
Location: IN, Indianapolis
Name: Mike
Vehicle Year: 2007
Vehicle: Chevrolet TrailBlazer
DriveTrain: 4WD w/ G80
Rank: Offroad Rated

by zeon_911 » Mon Dec 10, 2012 1:39 pm

im running almost stock, no lift. 235/85/16 mt tires. ive allready changed both o2 sensors and the cat was replaced as well thinking it was clogged (kinda smelled like it so i think it wasnt helping) new plugs with the gap correct. when i had the cat replaced i also had a compression test done and cylender 3 was low but not terrible
zeon_911
Cruiser
 
Posts: 45
Joined: Sat Apr 28, 2012 1:47 pm
Location: TX, amarillo
Name: william mitchell
Vehicle Year: 2003
Vehicle: Chevrolet TrailBlazer
DriveTrain: 4WD w/ G80

by dvanbramer88 » Mon Dec 10, 2012 2:01 pm

13 don't sound to bad. I was going to ask if it is cold where you are and than I saw Amarillo Texas. nevermind.

I'd say look into MAF sensor and throttle body cleaning.
Chevy Power!
Long live the Republic
"Violence is not always evil. The judicious use of violence and those willing to use it without hesitation is often all that stands between wolves and sheep."

Build Thread
User avatar
dvanbramer88
Lifer
 
Posts: 2283
Joined: Tue Jul 05, 2011 3:12 pm
Location: PA, Bristol
Name: Dave
Vehicle Year: 2002
Vehicle: Chevrolet TrailBlazer
DriveTrain: 4WD
Rank: Trail Ready

by fishsticks » Mon Dec 10, 2012 2:13 pm

2003..... no MAF.
11 Silverado LTZ - 6.2L/6l80, 2/3 drop, self tuned
85 Hilux - 3RZ, dual cases, caged, 40s, chromo everything
02 TrailBlazer LTZ - 35s, lockers, balls - Gone but not forgotten - Build
User avatar
fishsticks
Moderator
 
Posts: 4356
Joined: Thu Apr 01, 2010 11:30 pm
Location: WA, Vancouver
Name: Donny
Vehicle Year: Other
Vehicle: Other Vehicle
DriveTrain: 4WD w/ Aftermarket Locker
Rank: Extreme Offroader

by dvanbramer88 » Mon Dec 10, 2012 3:41 pm

fishsticks wrote:2003..... no MAF.


DOH :slap:
Chevy Power!
Long live the Republic
"Violence is not always evil. The judicious use of violence and those willing to use it without hesitation is often all that stands between wolves and sheep."

Build Thread
User avatar
dvanbramer88
Lifer
 
Posts: 2283
Joined: Tue Jul 05, 2011 3:12 pm
Location: PA, Bristol
Name: Dave
Vehicle Year: 2002
Vehicle: Chevrolet TrailBlazer
DriveTrain: 4WD
Rank: Trail Ready

by v7guy » Mon Dec 10, 2012 4:34 pm

dvanbramer88 wrote:
fishsticks wrote:2003..... no MAF.


DOH :slap:



You don't even own a trailblazer or envoy, you just give advice on em. We're taking that into account when we only make fun of you for the next couple days.
build thread

All things in moderation, including moderation.
Some people never go crazy... what truly horrible lives they must lead
User avatar
v7guy
Moderator
 
Posts: 3712
Joined: Wed Mar 09, 2011 10:17 pm
Location: NY, long island
Name: Jason
Vehicle Year: 2004
Vehicle: Chevrolet TrailBlazer
DriveTrain: 4WD
Rank: Offroad Rated

by Moots1288 » Mon Dec 10, 2012 4:35 pm

fishsticks wrote:2003..... no MAF.

Got em!
User avatar
Moots1288
Veteran
 
Posts: 1964
Joined: Fri Feb 24, 2012 8:42 pm
Location: Long island
Name: Moots
Vehicle Year: 2006
Vehicle: GMC Envoy
DriveTrain: 4WD
Rank: Offroad Rated

by 06MidnightBlue » Mon Dec 10, 2012 6:46 pm

fishsticks wrote:2003..... no MAF.


Skadoosh!!!
User avatar
06MidnightBlue
Addict
 
Posts: 597
Joined: Tue Jul 12, 2011 4:14 am
Location: CA, Sacramento
Name: Jeff
Vehicle Year: 2006
Vehicle: Chevrolet TrailBlazer
DriveTrain: 4WD

by zeon_911 » Fri Jan 11, 2013 9:22 pm

Sorry for the long time to post a response, school is starting soon and work has been killing me. I'm not sure, it isn't lacking power but when I get up on it it does smell like the cat is bad even tho I JUST had it replaced. I did just get some new tires and it has seemed to help some so I'm not so worried anymore but the now there is the question is the bad smell :lol:
zeon_911
Cruiser
 
Posts: 45
Joined: Sat Apr 28, 2012 1:47 pm
Location: TX, amarillo
Name: william mitchell
Vehicle Year: 2003
Vehicle: Chevrolet TrailBlazer
DriveTrain: 4WD w/ G80


Return to Troubleshooting