2000 chevy blazer 4.3l 4x4 about 143k on it . went a small hour trip recently and light came on all these codes came up P0146,P0101,P0147, C0222 . we are also losing / eating some coolant. im thinking clean the mass air flow sensor first??? one of the code fix says replace intake gasket which might be related to coolant loss or has someone seen this before and knows exactly what it is ? thanks

 

well p0146 is o2 sensor bank 1 sensor 3 {no activity}
p0101 is mass airflow sensor
po147 is same sensor as p0146 means heater or circut malfunction
c0222 is right front wheel speed sensor missing
so looks like 1 o2 sensor to be replaced , mass airflow sensor to be replaced and check the wheel speed sensor on the right side possible replacement
all and all not too bad should all be easy fixes and not too expensive
then just have to find coolant problem

 

I don't think all three things would go wrong at once I will clean the mass flow first and see what happens

 

Every thing at one time my guess would say electrical. Bad ground some place. I would start with unplugging every connector you can find and spraying them with canned crc marine electric contact cleaner. This and most important the connections to t the PCM. Due a search on all the grounds, Do them also.
You have too many codes all at one time for it not to be a contact someplace.


Next will be coolant leak, might be something simple.