I've replaced valve and the pump. Found a guy in Maryland that rebuilds them, if anyone needs that. Remember there is an electrical solenoid that opens and closes the manifold vacuum line that runs to the vacuum operated valve on the front of the cylinder head.

Anyway, what I've read is the the vacuum valves go first, allowing exhaust gases to flow back into the pump and ruining them. So, always check solenoid and valve operation when replacing one of these secondary pump

Where is the solenoid? The valves are different on 2004 to 3006 models. There's no tubing coming off my valve like the older models. Only two openings, one to the exhaust manifold and the other is the inlet port for the air pump

The air pump will not effect the MAF as it is not connected to the intake side. It flows into the exhaust side of the engine. As posted it will be effected by failed parts bolted to the 3.0 that provide air to it or down stream. Bench/car test with a separate 12V source (battery or converter) and confirm operations. Disconnect all the hoses going to it before testing as this will provide a baseline of operations, then connect everything back up.

On my 2001, the little tube on the vacuum valve runs to a solenoid that sits above the intake. I am not familiar for cars without that little tube.

If the vacuum valve (which also serves as a check valve) fails open ( mine did) then exhaust gases are pushed into the air pump and then back into the air cleaner box and the intake. The pump will overcome this flow, but it is usually only running for a minute at startup.

I can check it tomorrow if it doesn't turn on. But as I mentioned in post 18, the pump kicked on today ad it should have. No SES light came so for now I will leave it as is.

Your should look like this image

SPECIAL NOTE: BMW calls the sensor on the air intake to the pump a MAF also. It is different than the one near the throttle body. Part #8

If #14 fails, exhaust gases will flow into the pump, sensor, etc and will melt all the hoses one at a time.

Image Part Number **Description Each
*11727506210 *AIR PUMP*(from 10/03) 1 * NA
11727506210 was superseded by 11727571589.
1 *11727571589 *AIR PUMP*(from 10/03) 1 * $469.38
2 *11727506211 *RUBBER MOUNTING*(from 10/03) 3 * NA
11727506211 was superseded by 11727571866.
3 *11727515919 *BRACKET*(from 10/03) 1 * $21.56
4 *07119900272 *HEX BOLT WITH WASHER - M6X12-Z1-ZNS*(from 10/03) 4 * NA
07119900272 was superseded by 07119904517.
4 *07119904517 *HEX BOLT WITH WASHER - M6X12-U1-8.8*(from 10/03) 4 * $0.56
5 *07119904023 *HEX NUT - M6-ZNS3*(from 10/03) 3 * $0.50
6 *11727510956 *SUCTION PIPE*(from 10/03) 1 * $45.47
7 *07129952113 *HOSE CLAMP - L28-33*(from 10/03) 1 * $2.00
8 *51417067920 *FILLISTER HEAD SCREW - TS 5X16*(from 10/03) 1 * $0.53
9 *11721438814 *MASS AIR FLOW SENSOR*(from 10/03) 1 * $349.19
10 *11721438836 *SECONDARY AIR FILTER*(10/03 to 03/05) 1 * NA
11721438836 was superseded by 11727534722.
10 *11727534722 *SECONDARY AIR FILTER*(from 10/03) 1 * $21.39
11 *11727510955 *PRESSURE HOSE ASSY*(from 10/03) 1 * $28.24
12 *11727514860 *GASKET STEEL*(from 10/03) 1 * $7.02
13 *11721742644 *SELF-LOCKING HEX NUT*(from 10/03) 2 * $0.57
14 *11727508049 *VALVE*(from 10/03) 1 * NA
11727508049 was superseded by 11727553067.
14 *11727553067 *VALVE*(from 10/03) 1 * $131.67
15 *11727519292 *BRACKET SECONDARY AIR FILTER*(from 10/03) 1 * $30.60

Realoem shows the vacuum hose and solenoid on both 2001 and 2006 3.0L.

RealOEM.com - Online BMW Parts Catalog

RealOEM.com - Online BMW Parts Catalog

I am well aware. As mentioned earlier I replaced all secondary air system components except for the air pump as the pump. David X5, you may be confusing the primary and secondary air system. If the valve stays open the exhaust goes to the air pump and causes premature failure. It does not reach the primary air intake

Those are incorrect for 2005 year. Stephen showed the correct one