V70, 98, What actually sets the P0410 code?

Sailing_Faith · Post by **Sailing_Faith** » 27 Jan 2009, 17:15

Ok,

The P0410 code is know to all to be the supplimental air sustem. This system consists of a pump, a check valve, some hose and a pump control relay.... at least these are the failure points I have identified in prior posts.

Does anyone know what actually triggers the code to set? I am thinking there must be a sense wire on the (overpriced, $365) airpump. I doubt there is any kind of airflow sensor in the system, and I do not see the o2 sensor being used to verify the system is working (too many other codes involved in a rich run condition which is all the o2 sensor would see).

Anyone know what the computer sees to let it know to set the P0410 code?

Thanks,

Post by **MadeInJapan** » 27 Jan 2009, 17:45

Quoting from Bay13, this is what it says:
"The air pump system is emissions related and if not working properly will set codes in the ECM (Engine Control Module) and turn on the "Check Engine Light". The Air Pump is part of a system called the Pulsed Secondary Air Injection System (PAIR). The three codes that can be set are; EFI-442 PAIR flow fault, EFI-446 valve leakage, EFI-448 pump flow too high. The EFI-442 (P0410) is always set with either of the other two codes. When any of these codes are set, fuel trim is disabled."

Hope this helps. I would say the first is sensing the pump motor isn't turning (or at least turning enough)...the second is that it's turning too much (air leak- broken hose(s) or no vacuum due to issue with the SAS valve. Either way, you should change out the pump (either with new, good used, or rebuilt VW pump- there's a write-up on this in our repair database section) as well as the SAS valve.

mcp · Post by **mcp** » 27 Jan 2009, 18:21

It uses the 02 sensor by looking for a change when the SAS system is activated. No change, it sets the code. It does not know whether the air pump isn't working or if the SAS Valve isn't working, it just knows that the O2 sensor is not seeing a change when fresh air is supposed to be flowing into the exhaust.

minis · Post by **minis** » 23 Mar 2009, 11:38

I have a 1998 V70 T5 with 147k miles. I have a continuing problem with P0410 code coming up after replacing the pump, valve and carefully checking the vacuum lines, relay and vacuum switch. The issue comes up randomly (after clearing code) every 5 to 7 days stop and go driving, is it possible with this many miles it could be an O2 sensor problem? Thanks in advance for any help.