I have a check engine light I pulled the code 23: poor electricalconnection, open or short in circuit; defective MAT sensor, defective ECM, I recently changed the MAT sensor and to note the car was worked on by dyno don he didn't do anything wrong just looking for a quick response

 

start with the flow chart, and check the mat connection next to the distributor.

 

I drove the car and noticed that the check engine light comes on after the car reaches or passes normal operating coolant temp

 

I noticed that the wire that goes to the egr is broken at the porcelain material would that affect the mat sensor ...the sensor is good only thing I can think of is faulty ecm ground

 

Did you get this get this figured out. I have had same problem since owned mine? Very curious how u solved this? I know mine is warmed up when ch engine comes on? Quickly goes off when driving? Seems like as soon as it is not under load comes back on. Runs drives decent. Can tell by exhaust note it loads up, rich condition when ch engine comes one

 

Still figuring it out just trying to use the chart on top...same thing happens on mine check engine turns on as soon as it warms up but doesn't go away

 

What if I swap ecm to another one sensor checked out good wiring looks good

 

Well I swapped the ecm and same problem maybe the mat sensor

 

have you looked into the ground side. If I remember correctly the tps and mat splice for a common ground.

 

Will look at some diagrams on alldata