renix motor
 

New to the jeep world what is the diff in a renix motor and a non renix motor.

The computer system that runs it, and an unnoticeable horsepower gain on the 91+.
That's about it for the 4.0. The 2.5 was a little more different, they started off with a carburetor, then in the Renix years they were throttle body injected, then 91+ was MPFI.

A lot of people hate on the Renix Jeeps, but I love them, I own 3 of them.
Renix was 87-90 (86-90 for the 2.5), 91-95 was OBD-I, 96+ were OBD-II. Then a few things changed for 00-01.

Well stated and very true.

Hehe

Here's how I like to think of them:

Renault/Bendix "Renix": Adapts quickly on-the-fly to keep engine running well. Almost more "electronic" than "computerized", nearly everything can be tested with a multimeter. No codes. Very flexible platform. Renix Jeeps were built under the AMC flag under Renault ownership.

Chrysler OBD-I: Adapts over time and stores parameters in long term memory. Requires proper testing equipment, throws two-digt trouble codes for major systems only. Marketing ploy of "High Output" starts here. Chrysler took over production for the 1991 model year.

Chrysler OBD-II: Much better adaptive memory, fully computerized but up to modern standards. (OBD-II is the current standard protocol.) Detailed DTCs for most systems that can break, including emissions, transmission, airbags, etc.

There are other differences too, like OBD-II in 1997 made the very sane change of having a SINGLE temperature sensor. OBD-I has one for the ECU and one for the instrument cluster, Renix might even have three (electric fan); Renix and OBD-I make use of a vacuum-controlled fuel pressure regulator on the fuel injector rail and an in-line serviceable fuel filter, whereas OBD-II 97+ uses an in-tank filter and regulator.