Lifted 1990 renix, horrible mileage.
MJ>XJ
Joined: Mar 2009
Posts: 17,836
Likes: 7
From: Griffin, G.A.
Year: 1990
Model: Comanche
Engine: 4.0 I6
Originally Posted by freegdr
put 38s on it 35s to small for 488s lmop
Thread Starter
Seasoned Member
Joined: Feb 2010
Posts: 298
Likes: 1
From: so cal
Year: 1990
Model: Cherokee
Engine: 4.0
Injectors, are stock. I am going to check those this weekend. Fpr is from stroked jeeps. O2 sensor is brand new, and it is going into closed loop. Transmission is shifting fine, and locking up. Injectors are the only thing left to check, that I can think of.
MJ>XJ
Joined: Mar 2009
Posts: 17,836
Likes: 7
From: Griffin, G.A.
Year: 1990
Model: Comanche
Engine: 4.0 I6
Sounds like u dont have a problem at all to me... U may have a junk injecter but chances are it woukd spit and studder and run like crap...
Jeeps were never built for gas milage... Well until like 2008 lol
Jeeps were never built for gas milage... Well until like 2008 lol
CF Veteran
Joined: Nov 2011
Posts: 2,322
Likes: 1
From: Edmonton
Year: 1990
Model: Cherokee
Engine: 4.0
have you put a gauge on the rail yet? you have to set those regulators up with a gauge. it is the adjustable one right? then you should buy the map tweeker too...
CF Veteran
Joined: Mar 2010
Posts: 47,923
Likes: 38
From: Broward County Fl.
Year: 1989 xj sport 2dr
Model: Cherokee
Engine: 12 hole bosch Injectors
im running 38s on 410s im getting around 15 no complaints here but being stick shift makes a big difference and in running ac 24/7 . 703 injectors seem to pick it up a little
MJ>XJ
Joined: Mar 2009
Posts: 17,836
Likes: 7
From: Griffin, G.A.
Year: 1990
Model: Comanche
Engine: 4.0 I6
Originally Posted by freegdr
im running 38s on 410s im getting around 15 no complaints here but being stick shift makes a big difference and in running ac 24/7 . 703 injectors seem to pick it up a little
Senior Member
Joined: May 2009
Posts: 800
Likes: 3
From: The Dirty 530
Year: 1988
Model: Cherokee
Engine: 4.0 Renix I6
I'm running 3.07's on 32's 5th is almost useless on Freeway, and I average
15mpg. Thing is a dog.
Op with that newer motor, and proper tuning, you should be getting better
mileage.
MJ>XJ
Joined: Mar 2009
Posts: 17,836
Likes: 7
From: Griffin, G.A.
Year: 1990
Model: Comanche
Engine: 4.0 I6
Originally Posted by fallenknight308
Yeah something isn't right. Even for a stroker, it should be getting more than 8mpg!
I'm running 3.07's on 32's 5th is almost useless on Freeway, and I average
15mpg. Thing is a dog.
Op with that newer motor, and proper tuning, you should be getting better
mileage.
3.55 and 33's with a 5 speed was about right for me... Back to stock power and almost stock speedo settings...
Junior Member
Joined: Oct 2012
Posts: 93
Likes: 0
From: Blue Ridge, GA
Year: 1989
Model: Cherokee
Engine: 4.0
89 RENIX (stock 155k poorly maintained), AW4/3.55s/32x11.50 A/T here and I average about 14mpg around town, 16ish on the highway if I keep it under 65.......FWIW.


