GF14.30-P-2000CY Component Description For an Electric Air Pump

GF14.30-P-2000CY Component Description For An Electric Air Pump
ENGINE 272.911 in MODEL 204.0 up to Model Year 8
ENGINE 272.921 in MODEL 204.0 /2 up to Model Year 8
ENGINE 272.947 in MODEL 204.0 /2 up to Model Year 8
ENGINE 272.948 in MODEL 204.0 up to Model Year 8
ENGINE 272.961 in MODEL 204.0 /2 up to Model Year 8
ENGINE 272.971 in MODEL 204.0 up to Model Year 8





Location

126/1 Left air shutoff valve
126/2 Right air shutoff valve
M33 Electric air pump

The electric air pump is mounted upstream of the variable intake manifold.

Task
The electric air pump blows fresh air for air injection into the exhaust ducts of the cylinder heads.
The air injection allows afterburning in the exhaust ducts or in the firewall catalytic converters which brings the firewall catalytic converters more quickly up to operating temperature for a cold start.

Design
The electric air pump is an electrical vane pump.





Actuation (shown: engine compartment at left rear)

N10/1 Front SAM control unit with fuse and relay module
N10/1kM Starter circuit 50 relay
N10/1kN Engine circuit 87 relay
N10/1kP Secondary air injection relay

The electric air pump is actuated via the secondary air injection relay by the ME-SFI [ME] control unit (N3/10).





Function

M33 Electric air pump
a Air intake from right air filter housing
b Injected air to right air shutoff valve
c Injected air to left air shutoff valve

With air injection released, the electric air pump is actuated over the secondary air injection relay parallel to the air pump switchover valve for a maximum of about (Y32) 40 s. The power consumption at 13 V is approx. 45 A.

Here the electric air pump draws filtered injected air out of the right air filter housing and delivers it via two pressure fitting through the air shutoff valve to the exhaust ducts.

Following actuation, air injection remains locked. A new enable of the air injection will only take place if the firewall catalytic convertors cool down again due to a sufficiently long stoppage of the engine. The electrical air pump thus has sufficient time to cool down again.

Diagnosis
Air injection can be released for diagnosis with DAS for a max. of 2 minutes (for a warm engine only shortly).
Prior to the next actuation, it is essential to maintain a cooling time of 30 minutes, otherwise the electric air pump may be damaged (overheated).