Happy Sunday all,

Recently been having issues with my 233k+ 01 QX4 , so i need to stop being hardheaded and get it fixed before it gets worse (or is it already?)
Couple weeks ago, I experienced my car going maximum 30mph and couldn't pass 3k rpm. Almost got rear ended when headed for work at 7am. (Somehow spraying Mass Air Flow Sensor Cleaner, fixed it temporarily)

Recent Symptoms:
- After a cold start-up and forward progress, the idle revs up & down between 1-4k rpm and the car hesitates to move. After a couple seconds, it's fine.
- Sometimes when idling, the rpm drops below 1k and then back to normal. Once in a while, the rpm drops to zero and i'll have to start the car again during a stoplight.
- When idling, there's a weird smell coming from the exhaust. Smells worse when idling in a drive-thru.

- Not sure if this can be a part of the problem, but my oil cooler is leaking. I recently bought the small and large o-rings on ebay. Waiting to replace on my next oil change.

Your help is greatly appreciated!

Here are the codes:
1. P1145 - Manufacturer Control
2. P0171 - System Too Lean Bank 1
3. P0174 - System Too Lean Bank 2
4. P1145 - Manufacturer Control
5. P0171 - System Too Lean Bank 1

If this isn't against the rules, I can send $5-$10 via venmo/paypal for your help?

Hiyo! How ya doin'? How's the car? Not sure if you've figured something out since you made this post, buuuuuut I may have some insight.

If what you say is a stinky smell that can be described as rotten eggs or sulfur, that's got everything to do with a bad catalytic converter. They aren't cheap either. I can only assume because of the error codes that the banks themselves will need the replacement.

As for the P1145 code, here is what I found:

"Possible causes
•Faulty Intake Valve Timing Control Solenoid Valve
•Intake Valve Timing Control Solenoid Valve harness is open or shorted
•Intake Valve Timing Control Solenoid Valve circuit poor electrical connection
•Faulty Crankshaft Position Sensor
•Faulty Camshaft Position Sensor"

Maybe take a look at this video: it's about the first bullet: https://www.youtube.com/watch?v=fPqjJVHZS3I

I hope any bit of this helps in trying to find an answer. This forum has been a godsend for other mechanic's input. Two heads are better than one.

Good luck!

DTC P1140 (RIGHT, -B1), P1145 (LEFT, -B2) INTAKE VALVE TIMING CONTROL POSITION SENSOR (CIRCUIT)
Component Description
Intake valve advance unit position sensors are located in the front cylinder heads in both right/left banks. This sensor uses a Hall IC (element). The cam position is determined by the intake primary cam sprocket concave (in three places). The ECM provides feedback to the intake valve timing control for appropriate target valve open-close timing according to drive conditions based on detected cam position.
That is you P1145 code.

DTC P0171 (RIGHT, -B1), P0174 (LEFT, -B2) FUEL INJECTION SYSTEM FUNCTION (LEAN)
Possible Cause
Intake air leaks
Heated oxygen sensor 1 (front)
Injectors
Exhaust gas leaks
Incorrect fuel pressure
Lack of fuel
Mass air flow sensor