Yesterday at lunch, my Check Engine light came on. I performed the diagnostic to get the ECU code, and it reported "Engine Coolant Temperature Sensor." After work, I stopped at Auto Zone where I got the new sensor for $24.99. I went home, replaced the offending part, and reset the Check Engine light. All was good.

After driving for half an hour, the Check Engine light came on again. I again performed the diagnostic, and got codes for "EGR System Hi/Low Flow," "Knock Sensor," and "Rear Heated O2 Sensor."

Surely all three of these components cannot be defective, all of a sudden. What could I have done during the swap that is causing these ECU codes?!

Any help would be greatly appreciated.

 

You might need an o2 sensor. Reset it and see what comes back.

 

Anyone else want to chime in before I get my hands dirty?

 

Well i'm having the same damn problem with that code kinda. I got the code on my old engine, i changed the part and a week later the code came back (same code for me though) so i cleaned the connector with some wd40 and for like a month or 2 no codes...Then it came back so i just said screw it, not i've put a new engine in my car and got the same code yet again, i think its the wire harness connection thats actually the problem for some reason it gets so dirty which is odd cause its on top of the engine, maybe the fans blow crap into it i don't know really <shrug>