Okay, this isn't my trooper it's my father's. I'm trying to help him fix it because he is retired and on SS so he doesn't have the money to replace it, or even fix it for that matter so this is my pocket book.

The issues began not long after he purchased it and he has been told it is the "Mass Air Sensor" but I'm not positive about that.

It is currently throwing a Check Engine Light but the POS Chilton doesn't show the location of the ECM to find the jumpers and pull the code.

Whatever it is seems to be messing with the timing. It will cough and sputter and backfire at times.

The problem appears most in stop and go traffic (i.e. in town driving), but will appear when attempting to accelerate to pass someone, etc...

The higher the RPM's the less frequent the problem, but fuel milage is also a problem.

It's a 4 Cylinder and he is down to 14 MPG............

Anyone who can tell me where the ECM is and give me ideas on which sensor is the problem and how to test it is appreciated.

 

i think the ECM is between the front seats under the console ,if this is what you're talking about.

 

under the center console,the diag connector should be right beside it.it may have the 3 prong style or the g.m. style.if its general motors just jumper the 2 terminals that are the closet to each other on the end.88 dont have a good sophiticated system.it may be more of a mechanical problem such as worn carb,burned valves,vacuum leaks,fuel psi or volume.