**HELP please** Check Engine Light codes: P2629 & P0491

[HadesM3]

I have a 2011 M3 and recently encountered a SES “CC-ID 31” Increased Emissions. My car runs fine, but this SES comes on every time I drive the car. 

I also pulled the following codes w/ my OBD2 reader:

P0491 - Secondary Air Injection System Insufficient Flow Bank 1
P2629 - O2 Sensor Pumping Current Trim Circuit/Open Bank 2 Sensor 1

I have cleared the codes several times, but they come back after about 10 miles of driving. My car is currently bone stock with about 60k miles.

Should l replace the drivers side pre-cat O2 first according to the P2629 code? Is it possible something simply came loose like a wire? What is required to clear the P0461 code?

Thanks for your help!

[HadesM3]

Can anyone provide some guidance?

Thanks

[Ajolives]

What have you looked at so far?

I'd check all the connections to the secondary air pump, the line that runs to the elbow of the intake and back of the plenum. Make sure they're tight. Basically anything connected to the SAP needs to be looked over.

O2 sensor may be a secondary fault due to whatever is going on if I had to guess.

How many miles?

[HolyChitMeng]

I just got P0491 as well as an o2 code. I cleared both codes and the SAP code came back and the o2's came back later on. I replaced the primary o2's, but the SAP code still remains. P0491 which also shows up As 27B0, is calling for the secondary air injection control valve. I'm about to replaced both banks and the hose that connects to them.

[HadesM3]

Originally Posted by Ajolives

What have you looked at so far?

I'd check all the connections to the secondary air pump, the line that runs to the elbow of the intake and back of the plenum. Make sure they're tight. Basically anything connected to the SAP needs to be looked over.

O2 sensor may be a secondary fault due to whatever is going on if I had to guess.

How many miles?

I haven't checked anything yet. I am prepared to swap out the O2's, but want to do my homework before doing so. I am not familiar with the SAP, but will start researching and checking the connections as you recommend.

My car has about 60k miles.

Originally Posted by HolyChitMeng

I just got P0491 as well as an o2 code. I cleared both codes and the SAP code came back and the o2's came back later on. I replaced the primary o2's, but the SAP code still remains. P0491 which also shows up As 27B0, is calling for the secondary air injection control valve. I'm about to replaced both banks and the hose that connects to them.

How much work and cost is involved in changing out these control valves?



Thanks for the advice guys!

[amrazM]

Originally Posted by HadesM3

How much work and cost is involved in changing out these control valves?

Thanks for the advice guys!

Theyre both mounted upside down on the back of the engine also attached to the exhaust manifold heat shield, the upper nut and heatshield bolt are fairly easy to get out but the lower nut sits pretty recessed in and is covered by the manifold heat shield, most deep 10mm sockets arent enough to get in there, you'll need a stub of an extension to take it out.