I need help figuring out what could be wrong with the truck. The other day we had the truck scanned and the codes p0300, p0132, p0137 and p0157 came up. We cleared the codes, light came back on and now the codes are p0131, p0132, p0137 and p0138. I know what all these codes mean but I can't figure out the best approach to start to pin point the problems as so many websites say so many different things. What is the most likely cause with these codes all together?

 

I've been getting the 138 when idling for a long time since my exhaust upgrade.

Could they be from a bad or dirty o2 sensor?

 

Let me guess, 4.7 V8???

 

Nope it is a 5.7 V8. All wires look fine. reset the codes and now just P0132 is coming up. Wires all appear to be fine. truck only has 39,600 miles.

 

I think it's a bit more than a bad O2, because ALL of them are basically failing. This would be more indicative of an exhaust manifold leak or something along those lines.

Check the exhaust manifold for broken bolts, they like to rust off on the Hemis, a MAJOR issue in northern/salt states. Also the rather low use indicative of your mileage and/or short trips lend itself to exhaust rust and a few other problems stemming from the truck not being run at temperature for long periods. Could also be a gasket issue...

 

The exhaust manifold looks fine but do you think I should purchase a gasket set just to be on the safe side? They don't seem to be too expensive!

 

I don't think I mentioned that it has been idoling at low rpm's as well.

 

I had a problem with random codes and was my crank sensor. $64 here in canada worth a shot

 

There is a TSB for low idle and stall on '04s and early '05s, I've posted the exact TSB before if you wanna do a search. Has the PCM ever been flashed with this fix?

 

no clue as bought in in 2007 as a used truck. How could I find out?