1991 Montero, How to Retrieve CEL Codes

[ChuluTravels]

Good morning, happy Friday. I have a friend with a '91 Montero (that I've been trying to buy for several years, but that's another story) that has the check engine light on. Occasionally he gets some hesitation while accelerating. I want to help him diagnose the problem, but of course my OBD-II scanner is not able to read the codes. Can you tell me how to retrieve the codes from the ecu? Since I am not familiar with Mitsu's (I'm more familiar with honda, land rover, ford, chrysler) if you can tell me common hesitation problems to look out for that would greatly help also.

Thanks,
Sebastian

 

[off-roader]

Good morning, happy Friday. I have a friend with a '91 Montero (that I've been trying to buy for several years, but that's another story) that has the check engine light on. Occasionally he gets some hesitation while accelerating. I want to help him diagnose the problem, but of course my OBD-II scanner is not able to read the codes. Can you tell me how to retrieve the codes from the ecu? Since I am not familiar with Mitsu's (I'm more familiar with honda, land rover, ford, chrysler) if you can tell me common hesitation problems to look out for that would greatly help also.

Thanks,
Sebastian

Sebastian,

As you probably know OBDII only became available after 1996. Prior to that there was no industry standard.

For the Montero, it's simplest to use a multimeter (analog, not digital) and follow the procedure if the factory service manual (see mitsubishi links dot com).

As for the hesitation, it can be multiple things but without additional diagnostic info, I'd start by inspecting his plugs, wires, cap & rotor.

BTW, make sure it's the Check Engine light and not the Maint Req light. The Maint Required light is triggered when he reaches certain mileage whereas the check engine light illuminates when the ECU is storing a code.

HTH.