I changed my Air Filter over the weekend. I have my own custom SRI which has a specter filter.

The MAF went bad about 6 months ago so I replaced it with one from a 5th gen and bought a thermistor at the time.

Basically this means I have a 6 month old thermistor and the car was driving fine. I changed my air filter and replaced it with a newer specter air filter, the same as the one that was on there before but brand new, and drove around for a couple days. Now I get a p0112 and a p0127, both referring to the IAT (in this case thermistor).

P0112 - Intake Air Temperature (IAT) Circuit Low Input
P0127 - Intake Air Temperature Too High

I'm thinking of putting on my old filter to see if that keeps the light off. I plan to order a couple thermistors soon but I was wondering why a new intake would cause the CEL codes if the thermistor is relatively new.

Anyone have any ideas as to why I'm getting these codes after replacing the filter?
Could it possibly be a coincidence and be caused by the old filter not being efficient and dirtying the new-ish thermistor (although I don't really understand why that would cause it to not work)?

Car drives fine and only thing noticeable to me is the obvious CEL.

 

Maybe too much oil in the filter which contaminated the MAF. Head to the autoparts store and buy some MAF cleaner and clean the MAF thoroughly (but do NOT let the nozzle touch and sensitive parts).

 

I'll try that. However, the car doesn't exhibit any symptoms that a bad MAF usually causes.

 

As I suspected, cleaning the MAF didn't fix the problem. The car still drives fine but the CEL came back on for a p0112. I've placed an order for a few new thermistors and will install it when they arrive. That should take care of the CEL, although I'm not sure why the thermistor went bad after 6 months of installing it.

 

The thermistors I ordered came in yesterday. I replaced the thermistor and for good measure, cleaned my MAF again and reset the ECU.

Since then, after driving less than 25 miles, the same code has reappeared. The car still drives perfectly fine.

Any ideas on what could be the cause of this p0112?

 

check the maf plug for a loose or broken wire

 

Yea i looked at it yesterday by chance and i saw that some of the wires on the connector might have some of the wire exposed. I'm going to get some electrical tape on that since I just realized I fixed my p0113 like that last time.

 

Sometimes them damn contacts come loose inside the connector also if you look you can see one sticking up higher in the connector