Re: Does ECM = MCU ?
Taz is correct re: ECM. However, depending on your year jeep, you are going to have more than 1 module. On pre-FI jeeps with the computer controlled carb, you will have the ECM (commonly called the "Computer") that is mounted under the dash (typically on top of the heater duct) and it controls the Carb servo and the other emissions control, i.e., PCV solenoid, etc. Then located on the left fender well is the ignition control module (ICM). This is the standard Motocraft control module for the Duraspark system. Except for one wire, it can run the jeep without the ECM. The one wire is the feed for the coil. The ECM intercepts the signal and delays as necessary to compensate for inputs from the other sensors. The Nutter Bypass is a way of bypassing the computer. I personally don't know if it gains you anything over a properly running setup.
On later fuel injected engines, there is only the ECM or computer which takes all the inputs from sensors and drives the ignition and injectors.
Maybe we should get them to include a glossary for this BBS. Some acronyms have two or three meanings depending on context..i.e., R&P...is it Ring and Pinion, Rack and Pinion or Red and Pink?
84CJ7, 3"lift, 32"BFG, 4.10's, R/ARB, F/Detroit, Onboard Air....89 Cherokee - New Project
They say we learn by our mistakes.....I guess thats why we are all so smart.