improving H3 mileage?
Thanks
Member
Joined: Sep 2009
Posts: 45
First I would start by cleaning the MAF, throttle body, put some seafoam into the gas tank, run a can through the intake via the valve on the drivers side of intake. I do this every couple months and immediately my gas mileage, power, and throttle response go right back up. Plus you get to smoke out the neighborhood really good!
Another thing that I did which seemed to help increase the gas mileage, if your not on the skinny pedal a lot and if you have the $$ is to get the manifold replaced with a header, C.A.I., port the throttle body, pcmforless tune. What I noticed was I don't have to be into the throttle as much to get up to speed or whatever I'm doing, plus with the weight and the aerodynamics of a brick, more power is always good.
Another thing that I did which seemed to help increase the gas mileage, if your not on the skinny pedal a lot and if you have the $$ is to get the manifold replaced with a header, C.A.I., port the throttle body, pcmforless tune. What I noticed was I don't have to be into the throttle as much to get up to speed or whatever I'm doing, plus with the weight and the aerodynamics of a brick, more power is always good.
Last edited by mavrk73; Oct 4, 2012 at 02:33 AM.
Senior Member
Joined: Dec 2011
Posts: 379
From: Howell, MI
Before I try the PCM4Less tune, is there any way to tell if the used 07 I bought has it already? I saw the K&N, but the PCM4Less tune is just a re-flash and not a new module right? I get 17.5-18 avg on the hwy at 70-75 with a high of 19 once. 33" Wrangler Duratracs, no roof rack, etc.
Junior Member
Joined: Sep 2012
Posts: 2
From: North Carolina
Hey - I DID the PCM thing - had the work done in Mooresville, NC. Used to have a "P" rated tire, went up to t larger LT Michelin rated greener for lower rolling resistance. Use the best Castrol I can get, and add one blue plastic bottle of STP to the crankcase each oil change. Coming back this year from a deer hunt, clocked 17.5 mpg on the Interstate moving along with traffic that was in the 70-75 mph range (through mountains, not flat). That's running with a 6.0 liter replacement for the stock V-8.
Senior Member
Joined: Sep 2013
Posts: 142
Hey - I DID the PCM thing - had the work done in Mooresville, NC. Used to have a "P" rated tire, went up to t larger LT Michelin rated greener for lower rolling resistance. Use the best Castrol I can get, and add one blue plastic bottle of STP to the crankcase each oil change. Coming back this year from a deer hunt, clocked 17.5 mpg on the Interstate moving along with traffic that was in the 70-75 mph range (through mountains, not flat). That's running with a 6.0 liter replacement for the stock V-8.