Volvo runs great until it warms up. After warmup, idle will increase to 1500 and then increase/decrease quickly continuously. Engine throws two codes p0507 and p0122. Engine also goes into limp mode. This engine has no idle control valve so I’m thinking it’s the throttle body. Anyone have thoughts on what’s going on and why it fails darter warming up?

 

The P0507 is saying the idle RPM is too high and the P0122 is saying the throttle position sensor signal is low. Could be the throttle body (aka ETM) or could be the wiring/connectors. Check out sites like Xemodex to see what content they have about testing the ETM and the signal wires.