Truck throwing codes after new exhaust

[03KingRanch]

Since I've had my truck P0404 was the only code I ever had come up, it's an egr code, and it would do it every once in a while if I was puling a long grade. But after turning my truck on and off a few times, the CEL would turn off. I checked the egr valve after the first time, and it was clean, and my truck went through emissions testing with a very low opacity reading, so I never paid any attention to the code.

Well, I recently installed a new turbo-back exhaust system and noticed my CEL was on. I ran the codes and came up with P1509, P0113, P0118, and P1298(pending). No P0404 code. These codes are as follows

P1509 - Idle control system short circuit
P0113 - IAT sensor circuit high input
P0118 - ECT sensor circuit high input
P1298 - IDM failure

The truck runs absolutely fine as far as I can tell. No sputters or surges or anything that I have noticed. I have searched extensively and found nothing. Has anyone heard of this and had it happen to them?

[03KingRanch]

Has anyone had this combination of codes come up after any kind of engine work?

Someone told me that I should erase the codes and see if they come back up. I'm not real familiar with how the odb system works, is this a good idea? And how do you perform the injector buzz test?

[FamilyRide]

If you replaced the DP also, did you make sure no harnesses were left loose?

The easy way to clear the ECM/FICM/TCM is by disco'ing the batteries (turn on the head lights while the batteries are disco'd, turn the switch off when you reconnect) and see if they come back.

Just replacing the exhaust won't/shouldn't cause any DTC's. It's usually a harness or connector that gets lose.

[F250crazy]

Sounds like something is un-hooked. Was the key turned on before something was hooked up? False codes? Cat back system wont cause these codes.