Hi everyone,

I have a 2007 Range Rover with the 4.4 Jaguar V8 engine and I’m having some trouble getting rid of the check engine light.
The fault codes are for the mass air flow sensor (MAF) and alternating rich/lean mixture on both bank 1 and bank 2.

I first cleaned the MAF sensor, but that didn’t help. After checking for any cracked hoses or vacuum leaks, I followed ChatGPT’s suggestion to check the oxygen sensors (lambda sensors) using live data. They seemed to be working normally.

Oh, and I have replaced the air filter.

After that, I replaced the MAF with a new Delphi unit (same as the original), but unfortunately the problem remains. I still get fault codes for the MAF and for the mixture.

Typical codes I’m seeing are P0101-00 and P0171-00 (System Too Lean).

Does anyone have any ideas or suggestions on how to continue troubleshooting this issue?

Thanks in advance!

Smoke test, probably sucking in unmetered air somewhere.