1997 ford ranger 2.3

[preemanc]

i have a 1997 ranger with a 2.3 . i have recently been dumb founded with the code P0171 ( system too lean Bank 1 ) . I have changed fuel filter , air filter and cleaned MAF sensor , plugs and wires and i changer my intake gaskets and in the process of doing so i also replaced vacume lines with new . i did not even get 10 miles and the CEL is back on . Any input or advise in how to go about figure this out ?

 

[preemanc]

I have had the thought of maybe the IAC ( idle air control ) sensor could cause a lean code , is it possible ??

 

[koda6966]

It may. Check the PCV valve too.. I'm not sure.

You posted this in the 3.0 forum by the way.

Another thing to check, is that the MAF isn't too far gone. Sometimes cleaning them doesn't work.

 

[Precision Transmission]

Greetings,

Have you considered changing the upstream O2 sensor? If the sensor is bad, it can tell the TCM the bank is lean when it is not. O2 sensors usually need to be changed every 80,000 km (50,000 miles) for best performance.

Don