E200K, 2001, petrol, "Secondary Air Low"

[MFK]

The above car has done 91,000 Kilometers. Car was lacking power in low gears (most obvious in 2nd (autobox). It would not accelerate properly and then would all of a sudden power away and would drive perfect otherwise. I cleaned the throttle body and it did improve but not 100%. Car is due service in another 3K. Then Engine light came on and I took it to garage who cleared the codes and found a pipe blocked at back of engine and it has some valve on the line. All corrected but when he ran the car it keeps bringing up a code re SECONDARY AIR LOW (sorry dont know code number) - this is not bringing on the engine light but he doesnt know what to do next. Car is driving much better since pipe replaced.

Any ideas?

Thanks
MFK

 

[tech123]

i can remember something about a soldered connection in the wiring becoming dry and cracking causing this fault. it can be awkward and time consuming to find tho. i would recommend replacing the secondary air injection valve then tracing the wiring back to find the connector.

 

[Bobby Dazzler]

If memory serves, the secondary air injection pump/relay is only for US emissions regulations, and could potentially be removed for UK use.

I'm sure someone who actually knows about the stuff they type will be along soon, to either support or shoot me down.

 

[MFK]

Hi All, thanks for replies so far.

Could this problem be a Faulty Oxygen sensor just like the thread posted by BigD today http://www.mbclub.co.uk/forums/showthread.php?t=44622. The symptons are exactly the same in terms of driving performance.

Does anyone know if a faulty oxygen sensor would give a code referring to the Secondary air.

Any help appreciated

MFK

 

[MFK]

The codes were cleared but car is still not performning and I had codes read again. The garage changed all the secondary air parts off another E200 but the light came on after a week and car was not driving well - still lacking power etc.
Codes now show PO4010 with text saying air intake low. I assume this is still related to the secondary air problem. There was also a code PO2036 which was in the text section on the LAUNCH system
Any ideas?? - the garage are somewhat at a loss but have suggested that they change the pipework in the secondary air system - the one that runs across the engine under the radiator just in case there is some leakage etc. He said he would also try another throttle body on it.
Also the car is now drinking petrol.
Thanks for any help
MFK