rosenhanclan

I have a 2000 classic with the 4.0 and auto. Its lifted 4" on 31s. Im getting about 12mpg city and 14 hiway. Any tricks for bringing that up? One of the guys i work with has a stock 96 with 5 speed. He claims 23 hiway. I know i lose with the auto and big tires but should i really lose 10mpg with this setup?

cruiser54

He's BSing you.

jeep bandit

Maybe. But depending on how you drive. I bet you could get 23. But you should be able to get more than 13

DFlintstone

I'm no expert here but I maybe learned something last week. In a nut shell if the computer thinks the engine is cold it will enriches the mixture causing bad mileage. Warmed up it uses the O2 sensor to adjust the mix for optimum. Your 2000 may have a code thingy. Might even be a way to turn your key on and off and somehow and make a light blink in code on your dash. My stock 90 is only getting 16, (with 260+K), But I think its (Renix ?) might be in (open loop?).....maybe a temp sensor thing....There's a start. Let me know when you figure the rest out! Don

cruiser54

16 ain't bad on your Renix but I would suspect a bad or lazy O2 sensor. The O2 sensor is in play only in closed loop and the system won't go into closed loop unless the O2 sensor is doing it's job. The factory recommended replacing the O2 sensor every 67,500 miles.

DFlintstone

Way back when, did I hear they are hard to check? I seem to remember 18-22 back when gas was gas.

cruiser54

I check mine with my DRB-II so I'm spoiled. But, you can search and find other methods to check them with a voltmeter. Worthwhile in my opinion. Or, you could bite the bullet and replace it as a matter of course.

DFlintstone

I don't bite bullets. Scottish tight ***. Missing a briquette? I'm making a diamond as we speak! Yea...well my DBRBR..whatever is in the shop, voltmeter eh?

cruiser54

Yeah. EcoMike on NAXJA did a little write-up on testing the Renix O2 sensors. Your a$$ wouldn't be so tight if you weren't wearing a kilt!!!!

DFlintstone

EE---OW___I*** think A ohhhh Kilt might help this

EcoMike on NAXJA Guess I'll try a search....Was a nubee the other day.

That's funny! Wanna guess where the search got me? BACK HERE!

Found it, (for 87 to 90 Renix)

http://www.naxja.org/forum/showthrea...ht=sensor+test

I'm gone, didn't mean to hijack your thread, D.

excess650

Maybe not. My mostly stock '96 Sport with auto gets 21-22 on extended runs on the highway. We bought it new and it has always gotten better mileage running 89 octane vs 87. Higher than 89 didn't improve mileage.

DFlintstone

Not sure, but I think if you make it 8 feet high and put tires (as seen on TV) on it, in return you get on your fuel bill.

Slick761

@flinstone for some reason people tend to report a little better mileage with renix. On that note when I drove mine home on 33s it had open vacuum lines and some messed up wiring. I did however get 20+ on the hwy at 60mph the whole way. Since I have fixed everything its down to about 17-18 :-( city is crap though like 13-14

DFlintstone

"crap though like 13-14" is like what I get up north treating it like a tractor, yarden trees and dragging meat back to my cave.

Slick761

HAHAHA ya know you'd do better if you cut a hole in the floor Fred