# error codes : po491 & po492 need help please 5251t wagon



## 525itwagon2002 (Jul 22, 2009)

please help: error codes po491 and po492 (i had the codes printed out after service engine soon light came on).

491 and 492 say this:

secondary air injection system insufficient flow bank.
explanation:
damaged air system components.
probable cause:
faulty air solenoid valve
faulty air system relay

AND 491 also says this:

explanation:
the ECM detected that there was insufficient mass air flow change while the Air pump switching test .
probable cause:
1. secondary air vacuum hoses off or leaking
2. failed diverter valve system
3. failed air bypass solenoid
4. secondary air hoses off or damaged.

I DID REPLACE myself A HOSE THAT HAD A HOLE that was on right side of engine area when you stand at front of car and open hood, AND ONE THAT A MECHANIC SLICED THRU located to the left of the valve cover gasket when he changed valve cover gasket BUT I HAD THE LIGHT RESET AND IN 2 DAYS SERVICE ENGINE SOON LIGHT IS BACK ON AND 491 AND 492 ARE COMING UP ON MACHINE AGAIN.

can anyone help me if you had this happen or 
suggest what else i can fix.
i dont understand the air solenoid valve or relay
on printout.

i have to drive 1300 miles in a week and i am concerned
if car is safe and what else i need to do.
i am a girl and dont have the extra money to go to the
bmw repair place so i am trying to fix myself.

thank you to anyone who can suggest what the problem 
might truly be and how to fix.

cris


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