Fuel Mileage issue?
Thread Starter
Member
Joined: Dec 2007
Posts: 151
Likes: 0
Car: 1991 z28 L98 Spec
Engine: 5.7 350 TPI 245\345
Transmission: 700 R4
Axle/Gears: 3.23
Fuel Mileage issue?
Can runs amazingly, only down side is a code 42 that wont go away, will be checking it out tomorrow. Also only gets 13.5 mpg on the interstate?
Any suggestions guys?
Any suggestions guys?
Junior Member
Joined: Oct 2014
Posts: 24
Likes: 0
From: Midwest
Car: 1992 Z28 Camaro
Engine: 350 tpi
Transmission: Built 700r4
Axle/Gears: 3:42
Re: Fuel Mileage issue?
The 91-92 camaros had a fuel tank issue that was recalled, but few were fixed. If you smell a strong smell of gas for awhile after filling up, it may have a leak and need to be fixed. Not saying this is your problem, but its something to take a look at.
Senior Member
iTrader: (1)
Joined: Jul 2006
Posts: 506
Likes: 1
Car: 1989 GTA
Engine: 350TPI w/ Speed Density
Transmission: 700r4
Axle/Gears: Borg warner 3.27
Re: Fuel Mileage issue?
Code 42 is related to ignition advance. This could be the main cause of poor mileage. Lack of advance causes an incomplete burn of fuel.
Supreme Member
iTrader: (2)
Joined: Sep 2006
Posts: 2,118
Likes: 15
From: Houston, TX
Car: 1989 GTA
Engine: SuperRam 350
Transmission: Pro Built S/S TH700R4
Axle/Gears: 3.27
Re: Fuel Mileage issue?
If you adjust the base timing, you will get a code 42. Try adjusting the base timing to the factory spec. Then unplug the battery for 5 minutes. Re-connect and see how things go.
Thread
Thread Starter
Forum
Replies
Last Post
colton_carlson
Firebirds for Sale
7
Mar 8, 2019 12:21 PM
NBrehm
Engine/Drivetrain/Suspension Parts for Sale
1
Aug 25, 2015 11:49 PM




