CEL reading 4 codes, please help!

Hey guys, I have been a member on here for a while but haven't been active much because work is so busy and I forgot what my username was so I made a new one...(sorry mods). So here is my problem, any help would be greatly appreciated.

I have an 02 with the 2.7. The CEL has been on for a while but only reading the p0141 code. I replaced both O2 sensors about 6 months ago and the code didn't clear. I have a new cat and two new O2 sensors coming this weekend so I'm gonna swap all of that. But the truck has been running fine with just that code....Bigger problems started this week. It has been idleing really rough when I start it, and if I don't let it warm up it bogs down hard when I first start driving it but it will get me around.

I read the OBD and it gave me the same p0141 code (as usual) but it also spit p0171(bank one running lean) and p0172 (bank one running rich). ??????? It also read p1135, my code scanner asked my to input the model of the vehicle, I did, and its says "A/F sensor heater circuit malfunction bank 1 sensor 1". I am somewhat of a weekend warrior but I don't go much further then brakes, oil changes, maintainence etc. I do know alot about 12 volt and audio installation but under the hood....not so much.

Does anyone have any advice on where to start? I read something about cleaning/replacing the MAF sensor but I don't want to spend money with nowhere to start. Is this something I should go at myself or is it a more serious problem??

Thanks for reading all that, any help would be awesome. Thanks guys!

 

sorry, this posted twice for some reason

 

ttt, anyone??

 

no advice? anyone?

 

guess I'm gonna start by cleaning the MAF sensor. Thanks to anyone who helps.

 

p0171-p0172 is mass air flow failure. If you can, have fuel trim checked.

 

cleaned the MAF, that's not it. Going to take it up to my buddies now and pull it apart. He seems to think its a bad injector...