2015 Verano with p0097 p00f5 p0172 and p2199. Code reader says IAT sensor 2, but 2.4L engine only has one, correct? MAF replaced, problem persists!

[Jbridgfo]

Codes p0097 p00f5 p0172 and p2199, replaced MAF with non oem (gonna get OEM replacement). Code reader says IAT sensor 2 and sensor 1/2 correlation. Mine has the 2.4 liter non turbo engine, so there is only one IAT sensor according to my research. My (Cheapo) code reader is displaying IAT(F), IAT11(F) and IAT12(F). IAT 12 shows up about 20 degrees warmer than IAT, but as soon as the engine is shut off, the temperature on IAT12 drops to -40 degrees. (Code reader is a FOXWELL) What is IAT 11 and IAT 12 referring to? Do i need a firmware reload to tell the ECU that there is only one sensor? Hopefully a OEM MAF fixes this, but im doubting it. Thanks in advance!

 

[richardnewton]

We "caused" a bunch of MAF codes so not exactly the same experience. When changing the air filter, we pulled the MAF sensor for cleaning and then got a bunch of codes on our 2.4 (LaCrosse) related to MAF and intake air temp.

The wiring harness connector at the MAF is very sensitive. Make sure it is clean and has not bent pins or breakage. I would not use dielectric grease with that one.

- We ended up cleaning the connector with electrical connector spray and gently reseating the connector a few times.

- These engines are extremely sensitive to non-OEM parts so the "non-OEM MAF" likely will confuse your diagnosis.

The -40 degrees sometimes is a default for techs to show no voltage. But if you are seeing readings when the engine is running, I don't know if that would be an issue.

Maybe you can find the pinouts to your connector and check the voltages with a DMM. Make sure not to jam the probe into the connector which bends the pins.

There are pro service manuals availble for DIYers that are just a few dollars for a (month). Like Mitchell. Those might help with troubleshooting steps.