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shogun
06-21-2012, 02:54 AM
I thought the Vanos makes noise on my E36 M3 1998, almost ordered a repair kit. But now I found it is the subject which is the problem. As this also refers to some E34, here the details:

E34, E36, E38, E39, E46, E52, E53, E31 / M60/1, M62 LEV, M73, M73LEV, S50, S52,S54, S62, M54, M52TU, M52, M44, M43TU
Complaint: - Failure of secondary air system
- Entry in DME fault code memory "Throughput of secondary air system too low"
- "Check engine" lamp illuminated on US vehicles
Cause: Past experience has shown that the failure of the secondary air system is not attributed to a component fault in the secondary air pump but rather to the secondary air check valve not closing/opening or the actuating relay sticking.
- Secondary air check valve does not close:
The secondary air valve is located between the secondary air injection channel (either integrated in the cylinder head or on the exhaust manifolds) and the secondary air pump.
The electric valve switches through the vacuum from the intake system for the purpose of opening the secondary air check valve.
Due to soiling, the electric valve can no longer close mechanically. Consequently, the secondary air check valve is also no longer closed. Hot exhaust gas constantly flows through the secondary air check valve thus damaging it and possibly also the secondary air pump.
- Secondary air check valve does not open:
The secondary air check valve will not open in the event of the diaphragm leaking or sticking. Consequently secondary air injection does not take place although pressure is applied by the secondary air pump.
- Actuating relay stuck (sticking of relay make contacts):
After starting the engine, the actuation time of the secondary air pump is from 2.5 to 105 seconds depending on the engine temperature and engine speed.
The relay make contacts sticking or sporadically sticking result in continuous power supply or impermissibly long power supply to the secondary air pump.
The secondary air pump is not designed for permanent power supply and is operated up to its destruction.
Affected
vehicles:
E31 / M73
E34 / M60 B30
E36 (incl. Z3) / M43TU, M44, M52, M52TU, M54, S50, S52, S54
E38 / M52TU, M60 B30, M62LEV, M73, M73LEV
E39 / M52, M52TU, M54, M62LEV, S62
E46 / M43TU, M52TU, M54, S54
E52 / S62
E53 / M54, M62LEV
Production period: from introduction of the secondary air system
Procedure: Proceed as follows in the case of customer complaint:
- Actuation of secondary air pump via the DIS tester:

- Secondary air pump is not operative:
Check whether voltage is applied at the secondary air pump.
If not:
Check electrical lines and plug connections of the secondary air system and replace the actuating relay if necessary.
If so:
Replace secondary air pump and actuating relay.
Check whether the secondary air check valve is closed on conclusion of secondary air injection.
For this purpose:
Visually check the secondary air check valve for dirt/soiling at the pressure hose connection to the secondary air pump:
No soiling:
No further action necessary.
Soiling (black particles/combustion residue) found:
Replace secondary air check valve and electric valve (= solenoid valve that switches the vacuum from the intake system through to the secondary air check valve).
- Secondary air pump operative:
Check the vacuum hoses from the intake system to the secondary air check valve as well as the pressure hoses and pressure lines from the secondary air pump to the engine for leaks and correct installation:
If necessary, replace or correctly install leaking lines, leaking or bent hoses.
No fault found in lines or hoses:
In this case, the secondary air valve is stuck or its diaphragm leaking and therefore does not open.
Replace secondary air check valve.

copied from here
http://img27.imageshack.us/img27/7509/bmwsecondaryairsystemfa.pdf

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additional info I found:
When mine went out I called my local BMW shop and was told I was looking at close to $500 to replace this non-essential air pump---roughly $400 parts and $100 labor. I was able to take out the old one, get it repaired, and reinstall it for a total of about $100 plus 30 minutes of my time. The car ran fine for the week it took to do the R/R.

Everyone will tell you that the motor is not repairable--it is. A motor is a motor. The trick is that BMW makes it very difficult to get to.

I took the extracted motor, sans mounting bracket and air cleaner, to a terrific shop in my town, Boulder, CO. The owner, who is a fantastic old-world kind of guy, spent 5 hours in labor just trying to defeat the evil geniuses at BMW who don't want you to fix the motor. But once he got to the motor it took him only a little time to replace one of the bearings and put the thing back together. Bill, the owner, told me that he can probably fix the next one for under $100. BTW, he didn't charge me for the time it took him to figure it all out. I totally trust their work and their shop.

If you want to give that a go, you can contact them at bldrelecmotor@qwestoffice.net 303-443-1331

I'm sure you will have to pay shipping both ways, but it might save you $300 in parts costs (if you are careful about the rubber thingies.)

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removed my air pump, plugged up the hose from the non return valve, reconnected the electrical plug. I had intended on installing a new pump or the simulator. Anyway after about two months the check engine light went out and has never reappeared. It then passed the emission test. You can try this.
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After studying the whole thread
How-To: Replace Your Secondary Air Pump (1996-up E36 6-cylinder cars) - Page 6 - Bimmerforums - The Ultimate BMW Forum (http://forums.bimmerforums.com/forum/showthread.php?t=92029&page=6)

I investigated further. So the pump is repairable.
See here
BMW SMOG PUMP REPAIR - YouTube (http://www.youtube.com/watch?v=VeV-djm8b_8)
drill the rivets out and replace them with screws with bolts, 4mm and 40 mm long.

and that is apparently exactly what this company is doing, which sells reman pumps, they replace the bearing too.

BMW E36 323 328 m3 1996-1999 - Rebuilt Air Pump.com (http://www.rebuiltairpump.com/products/BMW-E36-323-328-m3-1996%252d1999.html)
Product Description:BMW E36 rebuilt secondary air pump. The pumps is disassembled, new main bearing is installed, armature is polished and the rest of the parts are cleaned, inspected and replaced as needed. Pump is then bench tested for 10 minutes. two year replacement warranty comes with your purchase. Your old pump is required as a core, we provide a free fedex return label, so once you or your mechanic has installed the new pump, you can return the old one to me at no additional cost. We highly recomend replacement of the check valve, if your pump has any signs of water in it or brown residue, you will need a check valve. A failing check valve is the most common cause of air pump failure
How To Test A BMW Smog Pump Air Injection Check Valve
How To Test A BMW Smog Pump Air Injection Check Valve - YouTube (http://www.youtube.com/watch?v=JwJASz4SkfY)