Hi guys,

I've been browsing the forums for quite a while, but only registered today.

This week my Intercooler Hose burst, which is quite a common issue with these kind of engines (Focus 1.8 TDCi 2009). So I bought a silicone replacement, which is supposed to be much better and replaced it myself... so far no issues.

After the wee drive, I have remembered that I forgot to connect the IAT sensor back... so I thought I can just connect it afterwards - I left the car to rest for about an hour and went back to connect it. After starting it I got an Engine Problem light, so I connected my OBD2 to Torque and it read code P0098 (Intake Air Temperature Sensor 2 Circuit High).

I thought - fair enough - the ECU seems to be confused, it's been running differently for the past week, and now I've installed a new pipe. I have cleared the code using the Torque app, and the error doesn't seem to be coming back. I have also measured the Intake Air Temperature and it's changing, but at a steady rate: 29-30C at idle and going down to 18-21C when driving.

So my question(s): should I be worried about the error code not showing up again? Are the temperatures alright? Am I measuring the wrong thing? Should I be getting a new IAT?

I have reserved a replacement if it's needed, so I can pick it up and replace myself (if it's easy?).

Cheers!

Got some advice on reddit... posting here for anyone with similar problem in the future:

• The IAT sensor is probably the only one reporting the temperature, so if the OBD2 temperature is changing, it suggests that the resistor in the sensor is actually working.
• The IAT will be usually a few degrees above ambient when rolling down the road, and several more degrees above that when stationary
• The error appearing and then disappearing might be due to the fact that ECU took couple of cycles before throwing an error.

I'll keep an eye on the temps and other stats through Torque just to be sure, but other than that everything should be fine!