What sensor should I change next?

I have changed the EGR and all 4 o2 sensors on my 1999 Ford with a4.2 v6.my obd 2 says I am still running lean on bank1 and bank 2.Is that the A.I.C.,MAP,or T.P.S. or am I way off?

What sensor should I change next?
Instead of wasting all that money throwing parts you don't need at the problem you could have taken it to a shop, had the problem properly diagnosed and repaired the first time for dramatically less cost.





This is why people shouldn't be allowed to have code readers. It just makes the aftermarket parts companies rich.





OK, I calmed down.





I assume you have codes P0171 and P0174, yes? If so, the possible causes listed in the diagnostic procedures are:


Fuel system malfunction


Secondary ignition system malfunction


Air intake or vacuum system leak


Exhaust leak near O2 sensor


Incorrect cam timing


Restricted air cleaner


Excessive internal engine wear


Ran out of fuel





If this vehicle is what I think it is, a 99 Explorer with the 4.0 OHC motor then I'd bet money on you having a vacuum leak. Not only that, I know where it is leaking - at the intake plenum gasket, which is actually a bunch of O-rings. Notorious problem on these engines. The rest of the parts you put in were totally unnecessary and probably working just fine.
Reply:That would prob be the map. If u still have problems with it after that, look at the computer it may be faulty as well.
Reply:I'm gonna lean towards a temperature sensor. there are two ...one runs the gage and the other runs the computer. the one with two wires going to it is the one you want to look at. This should be located on the intake near the thermostat housing. both should be located near one another...the one with only one wire don't bother with...the one with 2 wires..it's the one that sends the signal to the computer...try it...but it's not a cheap part...so be sure...run the codes again and be sure.





Hope this helps
Reply:there is a posiblity that the mass air flow sensor can be going bad