I am worried that both of you have opened up your exhaust and made it free flowing and the sensor that senses the exh backpressure for the 2ndary air isnt sensing enough back pressure.
You both have headers and MODIFIED exh after the cat. This worries me too.
But... on the other hand that code doesnt mention anything about the exh. only valves, pipes,hoses, and electrical components. Except here where i highlighted the condition of the moniter not running
P2441: Electromagnetic air switching valve is stuck closed or air switching valve No. 2 (Bank 1 and
Bank 2) are stuck closed
It
Specification
Item
Minimum Maximum
The monitor will run whenever this DTC is
not present
See page
DI-437
Atmospheric pressure 570 mmHg (76 kPa) -
Battery voltage 11.5 V -
Time after secondary air injection in operation
6 sec. -
AIR pump ON
Air switching valve ON
Air switching valve No. 2 (Bank 1) ON
Air switching valve No. 2 (Bank 2) ON
Engine RPM - 3,750 rpm
Delay time after engine started 6 sec. -
Air injection pressure sensor fail Not detected
TYPICAL MALFUNCTION THRESHOLDS
P2441: Electromagnetic air switching valve is stuck closed or air switching valve No. 2 (Bank 1 and
Bank 2) are stuck closed
Cumulative pressure pulsation
Less than 15 kPa (113 mmHg)
(when AI ON (Air pump ON, all of air switching valves are ON)
This maybe due to a free flowing exh.
I will try to call my factory rep and see what he says
Maybe you guys could try to re-install the factory cat back or manifolds and see what happens.AND /OR the stock intakes.
The sysem only works COLD.
I dont know what else to say
Here is more info on how that system works (see attachments)
The picture above show the MAF very close to the TB, maybe its to close and the ECU cant adjust fast enough.
Celicas had this problem on some aftermarket intakes. The MAF is in a certain spot on the stock intake for a reason.
The ECM estimates the amount of air injected to the TWC (Three-Way catalytic Converter) based on
signals from the mass air flow meter in order to regulate the air injection time.
__________________
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