AboutRoland Finston Expertise I specialize in Chrysler Corp. front wheel drive cars and minivans for the years 1982-2005 based upon my 50-year DIY experience and factory shop manuals. I don't have expertise/manuals for Jeeps, Trucks, SUV's, Imports. Today I will take questions one at a time from 8am-7pm CST, answering you within 1/2 hour. If I am shown as "maxed out" try again, in an hour, as I may be answering another question or otherwise busy. There are answers to ten thousand Chrysler questions at your finger tips: put a few key words in the "find" box (above) or click on "view past answers".
Question ENGINE LITE COMES ON PO138 ON 2004 CHRYSLER 300M SPECIAL WHAT IS THE DISCRIPTION AND/OR WHERE CAN I FIND OUT THE DESCRIPTION OF CODE PO138
Answer Hi Michael,
That code says the downstream oxygen sensor on the right side, rear of catalytic converter is showing a voltage that is high, suggesting it is shorted to the supply voltage. So check that its wires are not shorted together, and if not then replace the sensor.
Roland
