Is the stock o2 sensor on my 2002 a4 3.0 a 4 or 5 wire sensor? Some sites say 4 some say 5, and they only make an o2 simulator for 4-wire o2 sensors, so gotta know before I order! Thanks so much, and btw how many sensors total are there on my car? Thanks!
-Daniel

 

You have 4 02 sensors total, 1 pre-cat sensor and 1 post-cat sensor on each side. I recently replaced a post-cat O2 sensor on my 02 A4 3.0, so I know the post-cat O2 sensors are 4 wire and I would bet that the pre-cat sensors are 4 wire as well.

 

How do we know which sensor is bad? Each of the four cost about $100 at AutoZone and if they all need to be replaced then so be it but any help would be appreciated.

Codes: P0118 engine coolant temp high input
P0393 cam position sensor B bank 2 high input

These are probably coming from a bad O2 sensor, right? Car has 105k miles, 2002 3.0

 

My car gets above error codes.
I'm wondering if you fixed your CEL with replacing camshaft position sensor or O2 sensor?

 

Just replaced camshaft positioning sensor. CEL came back on- comes on an off now. Need to replace o2 sensors probably...

 

I'm geting P0431, P0421 (Catalytic converter) and P0393 (Camshaft position sensor).
Can you tell me what error code made you to replace O2 sensor and what error code fixed since you replace O2 sensor ?

Thanks

 

Thanks.
What error message getting Now?
Still P0393? which is cmashaft position sensor even you replaced camshaft position sensor.
Did you do yourself?

I'm planning to replace camshaft position sensor on driverside because of P0393 on my a4 3.0L

 

Mechanic replaced the camshaft position sensor at same time as gasket head cover. I don't recall the cost of each individually and if I were to guess I'd say it was $550 for both jobs. The CEL code last time was for low coolant, which was low and I topped off. Now CEL comes on and off- again probably the O2 sensor is trippy?

I could be wrong but the CEL likes to come on after I put new gas in the tank. I haven't had a code pulled since topping off antifreeze. I will try to get codes updated during oil change on Saturday.


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Not proofread

 

I got used A4 recently, 2001 2.8L Manual and 2002 3.0L Auto.
Both got CEL soon after we got.
2.8L I don't remember but related secondary air and
3.0L got Code P0393, P0431 and P0421.
I did many research and checked for both.
I can tell both car had leak on vacuum hose.
All that related emmisions
Please check vacuum hose and connections, secondary air and Intake manifold flap valve actuator.
I can send drawings and Pic's if you give me email address.

 

Hi I'm also getting all the same codes you had got, did you fix all 3 codes to get your check engine light off? how hard was it to change the camshaft position sensor & O2 sensor? I'm thinking about doing it all myself.