My 2000 blazer has recently had a new issue with the Service Engine Soon light flashing, and the idle is really erratic, with it wanting to die. I put new plugs, wires, cap, rotor, and coil. A scanner coding the MAF and random misfires. Replaced the MAF and still running really rough. Put a scanner on it again and got codes on the crankshaft position sensor and throttle position sensor. I replaced them and still running rough, wanting to die. I don't know what else to check. Can anyone help with some suggestions?

 

if there is a slight rattling sound somewhere and it feels like power is running 50% and you get a P0420 and MAF code .. well, when that happened to me I got a new catalytic converter and all was well. I did not have a flashing SES, though.

 

Check the stability of the reference voltages at a few sensors.

An exhaust restriction would cause a significant loss of power at full throttle.


George

 

Changing the crankshaft position sensor requires performing a crankshaft position re-learn be done. This requires a scan tool capable of putting the PCM into the correct mode. Plenty of threads here that gives all the details.
Also be sure to check the camshaft retard setting.