Okay so im driving along and the car just starts backfiring and stumbling out of nowhere.

My problem is basically the car will start and run okay but obscenely rich and try to stall its self out. When you drive it down the street and back it starts popping and stumbling which im thinking means its switching into limp home mode.

I have 40-42 pounds of fuel pressure. I know the problem is not the coil, the ignition module, the map sensor, the 02 sensor, the coolant temp sensor.

I also know that its not dropping any cylinders.

The only thing i can think of is that my ecm is toast? I have no other ideas at this point.

 

Are you sure it's not the coolant temp sensor? Just because the temp guage is okay doesn't mean the CTS is okay - the computer uses a different sensor than the one that drives the instrument panel gauge. Check the TPS as well as the MAT sensor. Got to be one of those unless it's jumped time somehow if the other stuff you said is okay.....

Got any way to datalog it to see what those sensors are reading?

 

i replaced the CTS and the 02 sensor, and i know the map sensor is fine because i unplugged it while the car was running and the car ran noticeably worse.

i have no way of datalogging the stuff no scanner but i hotwired the connector and the car didnt flash me any codes.

How do i check the tps and mat sensor

 

if you don't have codes try looking at tune up parts and adjustments