Secondary air pump causing fuse to blow

[Sean545]

Hi all thanks for your help.
I have a 99 540i sport with a Dinan intake and exhaust. My problem is the secondary airpump is causing the fuse to blow. The air pump works but when it comes on the fuse blows. The air pump sounds a bit weird also .any ideas I changed the airpump in aug and haven't drove the car. So to be clear the air pump does not start due to the fuse always closing on load.
Thanks again

[BMW540san]

Your SAI control valve might be the culprit, #8 here:
http://www.realoem.com/bmw/enUS/show...diagId=11_2285
It's well known issue where over time build up of exhaust gasses or broken vacuum line that controls the flap inside, causes it to get stuck in closed position. Then your pump comes on at which point if flap is closed, it's going to strain and cause fuse to melt.

[JimLev]

Did you put a new or used pump it?
You said the pump make a weird noise when it comes on.
If your secondary air valve is stuck open exhaust gasses will get into the pump and cause the bearing to fail, that could be the noise your hearing.

[Sean545]

The pump is not allowed to run because the fuse blows

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Thanks

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The pump is rebuilt. I have to change this pump every two years. I took the pump out and placed 12vlots on it and the pump sounded funny also like it was struggling.

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Thanks for reply will check it out. But the pump can't even run because the fuse shuts it down.

[JimLev]

If the pump keeps blowing fuses it bad.
If your replacing the pump every two years, the secondary air valve could be bad too, which is taking out the pump.

[Sean545]

Ok I will change both and the fuse. Should I get another rebuilt pump or buy one from brav auto

[JimLev]

A new on will last a long time, mine is 15 years old and still fine.
Where are you getting the rebuilt ones from?

[jstern]

At the shop I used to work at the techs always insisted in changing the SAP relay when they replaced the pump. The pump tends to cook the relay as it fails. A cooked relay tends not to supply the pump with the correct electrical current causing the pump to fail again and perhaps make strange noises while it is doing so.

[cnn]

A few years ago, I spent many hours trouble-shooting the SAS system and wrote a few DIYs.

Fast forward to now, many modern BMWs use cam shaft modulation to control pollution, so the SAS concept is more or less obsolete.
Do I care about it? Yes b/c of the 100-sec run that may or may not affect the environment.
Do I care about SAS? No, I already d/c the relay, placed a small electrical tape over the annoying CEL light in the dash. Then once a month I scan for any new codes (other than SAS codes).

Problem solved, never look back on this garbage SAS thingy...

[bimas]

Good note about the relay!

My pump blew due to the valve being clogged. It busted the hose as well. Replaced all 3 components (~$500 in parts). All set.

I would delete it, but you can't in a legal road car in California. Moreover, you must put some serious miles on the car or reset the drive cycle (nearly impossible without completely controlled environment) to get the emission system ready for smog. It's a racket here!

[fullthrottle540]

I would delete it, but you can't in a legal road car in California.

This is where it gets tricky.... is there any way to delete it without check engine light?

[JimLev]

Some have coded it out and removed the pump. Does the CA inspection Nazi's listen to see if they can hear the pump running? If so your out of luck.
I've never followed the Drive Cycle routine, just drive the car for 2-3 days like I always do and the DME is "ready".

[bimas]

Some have coded it out and removed the pump. Does the CA inspection Nazi's listen to see if they can hear the pump running? If so your out of luck. I've never followed the Drive Cycle routine, just drive the car for 2-3 days like I always do and the DME is "ready".

They don't listen to the pump. Plus the car is warm by the time you get to the smog station, so no one should expect it to be on. They only look at their computer. If you recently deleted emission deleted codes, it will say something like 'not ready' for one of the categories. So, few days of driving or drive cycle reset will be necessary, with the stupid SAP system working. If there is a way to tell the DME to stay 'ready' with coding, than there is a way to delete it properly.

Edit: The salmon relay is about $17. I'll get one asap, just in case. Part #: 12631742690.

[Sean545]

A place I saw on this forum

[VTROADSTER]

I had problem too and after all changes still did not work, took out the relay bench test it was OK ,but put back it did not activated . pull out and clean the connectors on relay= problem solved

[Sean545]

That sounds like it . Thanks I will also check that out

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I looked up a place on this forum. I have a two year warranty on it. So I will send it back

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Yea I feel the same way but I need it for inspection.

[Kirk Anderson]

Isn't that one of the notorious under-passenger-seat fuses? If it isn't, could you let me know which fuse is blowing? I can't find this on fuse diagrams.

[JimLev]

Isn't that one of the notorious under-passenger-seat fuses? If it isn't, could you let me know which fuse is blowing? I can't find this on fuse diagrams.

F107 is under the pass side carpet. It's the first one on the left side looking at it from the pass side door.