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Tips for improving Gas Mileage
#47
CF Veteran
Join Date: May 2012
Location: Lost in the wilds of Virginia
Posts: 7,964
Received 951 Likes
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767 Posts
Year: 1998 Classic (I'll get it running soon....) and 02 Grand
Model: Cherokee (XJ)
Engine: 4.0
When gas was consistently over $3 per gallon, driving an econobox was going to save me a whopping $1000 per year.
And then there's additional insurance and maintenance. It's probably a break-even proposition.
#48
Improve mpg
Move your air temp sensor form your intake manifold to the air box doing this I had a 5 mpg increase highway and a 3 mpg increase city make sure to seal the original hole well, I used a brass plug 1/2" by 20 thread
#50
Old fart with a wrench
Running on Propane works well, but it takes big bucks to get it certified over here. The system has to be installed by a certified technician and any repairs have to be made by a technician also. Actually the latest system is LNG (liquefied natural gas) although the system runs on compressed natural gas because carrying a liquefied gas bottle is considered too dangerous for the public because of the extremely high pressures involved. Currently there is only one place in my area to get your system filled and that's the local bus service garage. In order for natural gas to stay liquefied it must be below -259* F or it turns to CNG at around 3,600 psi so you'd be driving around with a bomb in your car.
Which brings around a point. Where do you mount a propane tank in your jeep?
Last edited by dave1123; 07-12-2019 at 10:10 AM.
#51
Old fart with a wrench
After my last post, I did some research. It seems propane contains 2.5 times the BTU output of natural gas per cubic foot. It's also safer and easier to handle. There is also the fact of the infrastructure available to handle it. SO, even though natural gas is cheaper, it's less effective and more dangerous to handle. It seems natural gas at the wellhead contains methane, propane, butane and other lighter gases and is "cleaned up" so only methane comes out of your pipes at home., after the addition of mercaptan so you can smell leaks. 60% of propane is made from natural gas and the rest from distillation of crude oil. SO after the crude is gone, we'll still have propane to drive our jeeps! Provided the internal combustion engine survives that long! LOL!
Last edited by dave1123; 07-12-2019 at 11:24 AM.
#52
#54
The following 2 users liked this post by BlueRidgeMark:
2000_silver_xj (12-19-2019),
Spencer_P (12-19-2019)
#56
unfortunately me either. I'd love to have or running right but afraid I'm have to sell it or trade it off. I can't afford excessive fuel cost. And already spent my extra on mechanics. (Fixed income)
#57
Senior Member
proper plugs(which are probably champion copper) do not run the fancy ones. You will probably find the recommended plug on a sticker under the hood. take out the slack in the throttle cable. Finally, change your oil regularly.
#58
CF Veteran
Join Date: May 2012
Location: Lost in the wilds of Virginia
Posts: 7,964
Received 951 Likes
on
767 Posts
Year: 1998 Classic (I'll get it running soon....) and 02 Grand
Model: Cherokee (XJ)
Engine: 4.0
Actually, since he's got a 99, I'm not sure. The later models were better served by the NGKs, but I'm not sure where the cutoff is. Maybe with the 2000 when the coil packs came in?
The following users liked this post:
BlueRidgeMark (12-20-2019)
#60