SES Codes - P0070, P0071 & P0074

[das boots]

Opening a new thread for help in a diagnosis.

After getting codes to my SES from AutoZone and further reading online for what codes entails, I have learned quite a few lessons and would need more to continue.

P0070 - Ambient Air Temp Sensor Circuit.
The ambient temperature sensor helps the engine control module (PCM) determine how much fuel to use on startup. The PCM also uses this signal as a logic reference for other temperature sensors on the engine. If the PCM detects an issue with the signal from this sensor, it will set code P0070.

P0071 - System Too Lean (Bank 1)
See P0074

P0074 - System Too Lean (Bank 2)
Same as Bank 1 since our 330i has 6 cylinders.

Common Problems That Trigger the P0174 Code

•PCM software needs to be updated

•Vacuum leaks (Intake Manifold Gaskets, vacuum hoses, PCV hoses, etc.)

•Mass Airflow Sensor (MAF)
•Plugged Fuel Filter or weak Fuel Pump
•Plugged or dirty Fuel Injectors

I will open up my intake air and check out the MAF and Rubber Boot to check for vacuum leaks or breaks. How do I clean the MAF?

Thanks.

[das boots]

Found a tear in the Lower Intake Tube Elbow. Time to order the whole Upper and Lower Rubber Boot Elbow Set.



3' E46 330i Hot-film air mass meter
Hot-film air mass meter


01 Hot-film air mass meter 1 13627567451 $402.32
01 Hot-film air mass meter 1 09/2002 13627566983 $402.32
02 Hose clamp L95-102 1 07129952137 $1.52

03 Rubber boot 1 13541438761 $28.30

04 Hose clamp L83-90 3 07129952133 $1.78

05 Ring 1 13541438760 $1.93
06 Tube elbow 1 13541438759 $13.88

[Phillips0417]

That’s exactly where you should have started. Intake leaks are the most common source of P0171 & P0174. You should not need the plastic sleeve, just replace the upper and lower intake boots.

[Vas]

That’s exactly where you should have started. Intake leaks are the most common source of P0171 & P0174. You should not need the plastic sleeve, just replace the upper and lower intake boots.

And the F-Connector plus the short amount of vacuum line.

[das boots]

Ordered Intake Boot Upper and Lower. On the way.

The tear was in the F Connector in the lower boot. Very well hidden. Had to feel my way to find the break.

[das boots]

I have now replaced thr Upper and Lower intake Rubber Boot. See the big tear in the Lower Rubber Boot.

Now....how do I reset the SES? I tried the Peake Diagnostics. It was giving me Error messages. I went to O'Reilly's and AutoZone. They do not reset codes anymore. They were sued at one time so they stopped that process.

Is there another way?


3307333074

[das boots]

Got it reset from a friends shop. But found another fault. The Temp Sensor.

How often do Temp Sensors go bad?