Code for transmission sensor but runs great

johnnyboy1950

No slipping or jerking. 4wd works fine. Mechanic thinks ECM might be bad sending ghost signal. Cleared code and came back on. What is the best place to get ECM "flashed" or reprogrammed??? Does this sound like a likely fix???

johnnyboy1950

Sorry...2000 Blazer 4WD 4.3L seems to run great with no transmission problems. Mechanic thinks it may not be shifting into overdrive but I'm turning 2500 rpm at 70mph.....

Mr_Shiftright

So if I'm reading this right...your transmission does not exhibit any problems but it is throwing a code? What is that code #? You can count the shifts to determine if it's in overdrive---also you should have an O/D "off" button that will cause a downshift if you press it--that would also tell you that you were in OD.

johnnyboy1950

@Mr_Shiftright thanks...I'll try to get code, but overdrive seems engaged when I downshift...do you think my ECM may be throwing ghost codes?

Mr_Shiftright

It's my understanding that if an ECM is throwing false codes, it's going to throw a whole bunch of them all over the place. So that speculation, while possible, seems to be a less likely one. If you had the code, perhaps this sensor that's indicated could be tested in place.

johnnyboy1950

Thanks @Mr Shiftright I'll try getting sensor tested. I appreciate an unbiased opinion!!!