Air Pump Control Valve

[ClutchJones]

After my pleasant surprise of having my catalytic converter covered by warranty and paying $0 to replace it, I have now learned I need to replace the air pump control valve for the secondary air pump. Does anyone have any knowledge of this area? I have seen the part online for about $70, but I don't have a manual or any experience with the part and am not sure I can tackle it. I'd love to do it myself, rather than pay the dealership the $250 they quoted me.

[CirrusSR22]

Are you talking about part #15 in this diagram? Part #10?

http://www.realoem.com/bmw/showparts...58&hg=11&fg=45

My car doesn't have one, but from the pictures I've seen, part #15 looks very exposed. I bet it would be an easy fix.

[ClutchJones]

Originally Posted by CirrusSR22

Are you talking about part #15 in this diagram? Part #10?

http://www.realoem.com/bmw/showparts...58&hg=11&fg=45

My car doesn't have one, but from the pictures I've seen, part #15 looks very exposed. I bet it would be an easy fix.

It looks like part #15 in that diagram. Thanks for the diagram. It does look pretty simple. the next question would be, do you have to replace a gasket, seal or hose?

That secondary air flow pump has screamed when the engine is cold for the last 70k miles, but now it makes a slightly uglier noise and threw the code at the dealership when I was getting my cat replaced. The code said it was that valve, but I still find it weird that it happened right after I took it and got warranty work done... I think the valve is an easy replacement, though. It's a $75 part online and they wanted $250 to do it. I'd prefer to do it myself.

-Clutch

[BleMW]

it is part #15.

[DeadpaN]

I'm replacing mine again.
try autohausaz.com

Gasket $3.25 Part #11727505259

Check Valve $56.90

Part #11721433713

And what do you know?.....Everything over $50 ships free :]

[ClutchJones]

Originally Posted by DeadpaN

I'm replacing mine again.
try autohausaz.com

Gasket $3.25 Part #11727505259

Check Valve $56.90

Part #11721433713

And what do you know?.....Everything over $50 ships free :]

Thanks, DeadpaN. Is that all I need to replace it? Any extras like sealant for the gasket?
How long did it take you?

[cooljess76]

Check the secondary air pump. It's on the drivers side of the engine bay directly under the MAF and intake boot. It's shaped like a pancake and has a grey plastic body. Stick your hand around it when you first start your car while the engine is cold. See if you could feel air escaping from it. It's held together by 6 aluminum rivets which are very flimsy. 3 of the 6 rivets were broken on mine and air just gushed out of it. I noticed prior that it had became really loud when I started my vehicle. It's pretty easy to remove and I just removed all six of the rivets and replaced them with bolts/nuts. Works perfectly now and it's much quieter.

[DeadpaN]

yeah, its just the two copper 10mm nuts under the valve, (a deep socket makes this easier and faster); and the the two hoses. should take less than 30min./30mins. max.

[ofset]

Originally Posted by cooljess76

Check the secondary air pump. It's on the drivers side of the engine bay directly under the MAF and intake boot. It's shaped like a pancake and has a grey plastic body. Stick your hand around it when you first start your car while the engine is cold. See if you could feel air escaping from it. It's held together by 6 aluminum rivets which are very flimsy. 3 of the 6 rivets were broken on mine and air just gushed out of it. I noticed prior that it had became really loud when I started my vehicle. It's pretty easy to remove and I just removed all six of the rivets and replaced them with bolts/nuts. Works perfectly now and it's much quieter.

old thread bump. if air is escaping during engine start up, is this a sign that the rivets are bad? or the air pump itself is bad?

if air is escaping during engine start up will only during those 30-45 seconds, will this cause a CEL to come on?

just changed the ccv/pcv runs a lot smoother, but now im thinking i should change the shut off valve. but if the air is escaping from the secondary air pump, will this cause engine misfires?

thanks

[ryszardsh]

The secondary air pump should only run for a few minutes at most at cold starts. Its purpose is to pump oxygen into the exhaust stream which, combined with the extra fuel the computer is pushing on cold start, heats up the cat quickly to get it on line and catalyzing. Do the check Jess suggested, if you feel air from the circumference of the pump then the crappy little rivets need replacing. The pump may have that problem, you may have a cracked line from the pump to the air valve, or something is not plugged together properly from the valve to the exhaust manifold. The CEL should only come on if the cat is not heating properly at start. Really simple system and easy to fix (esp. since it is all on top of/in front of the engine).

RAS

[ofset]

Hey RAS thanks for replying. checked it this morning and its definitely leaking from the front of the pump only. (maybe the rivets in the back are fine) so ill probably just replace all of them just to be safe.

I was getting misfire codes and took it to the mechanic to change the PCV/CCV valve. Now i am thinking that the misfire codes are from the SAP

I also just replaced the line from the SAP to the Shut off Valve that is connected to the front of the engine.

I also unplugged the hose that goes to the shut off Valve to see if it kicks air out instead of sucking in. seem like its not pushing air out so the shut off valve should be in good shape.

[cooljess76]

Originally Posted by ofset

old thread bump. if air is escaping during engine start up, is this a sign that the rivets are bad? or the air pump itself is bad?

if air is escaping during engine start up will only during those 30-45 seconds, will this cause a CEL to come on?

just changed the ccv/pcv runs a lot smoother, but now im thinking i should change the shut off valve. but if the air is escaping from the secondary air pump, will this cause engine misfires?

thanks

The pump housing is composed of a series of plates stacked and riveted together. If you hear the pump kick on and then feel air escaping, chances are the pump is still good and just needs to be bolted back together. Replace the rivets with nuts and bolts and it should be fine. If that doesn't fix your issue and you still find that you have a misfire, check the ribbed rubber intake boot just downstream of the MAF for leaks using the brake cleaner method:
http://www.318ti.org/forum/showpost....9&postcount=15

[ofset]

ok cool. I just replace both ribbed intake boots about 3 months ago so those are brand new. but thanks for the tip. its good to know for future reference.

[ofset]

Hey CoolJess, thanks again for the tip on the intake boot. After looking closer, (re-looked 3 different times) it looks like the clamp around the end of the first intake boot after the MAF was not attached properly. from the top/side it looked like the clamp was attached correctly around the rubber part of the boot. but looked underneath the boot and the clamp did not attach to the rubber. so even tho the boot was brand new, it was not properly attached to the metal connector between both rubber boots. Air was definetly sneaking in from the boot not being properly attached.

so now i have a new PCV/CCV valve, new intake boots. I havent done the SAP rivet job yet. (am doing it this weeekend)

However when i took the car in to get the PCV valve replaced the mechanic mentioned that the misfires was being cause by a bad SHUT OFF VALVE, or EGR valve as he liked to call it. its the emission control valve (11721433713) that was causing the misfires.

now before i go out and spend another $75 on a new valve, I am hoping that fixing the rivets on the SAP will cure the misfire codes.

Do you know if the shut off valve is always working? or it only works when the SAP pumps air into the system. I havent been able to find out much about this Shut off Valve (11721433713).

thanks for the advice again.

[cooljess76]

I think it's just a check valve to keep air from the exhaust from backflowing to the SAP. I could be wrong though as that's just a guess. If you seen the boot misaligned, I'd be willing to bet that you've found your problem. The slightest bit of unmetered air entering the system, and by "unmetered" I mean air that hasn't been measured by the MAF sensor, will cause a misfire. The air/fuel metering system is very sensitive to this. That's why I HIGHLY RECOMMEND the brake cleaner trick. When you spray brake cleaner on and around the hoses, it atomizes and gets sucked into any tiny cracks or leaks. As the vapors get sucked into the engine, they'll ignite and you'll hear a very distinct fluctuation in rpm's. It'll sound like someone is in the car revving the engine. The brake cleaner gets in places your eyes can't see. If you would have performed this trick BEFORE you went poking around and found the misaligned boot, you could have positively identified the boot as the source of the misfire as you would have heard the RPMs ramp up. But since I'm assuming you've already secured the boot properly, you should still perform the brake cleaner check as there may be more than one leak. Also, before you pull the SAP, let the car sit overnight, pop the hood, start the engine and feel around the pump to see if you still notice air blowing out of it. The air you felt before may have been escaping from the intake boot while the pump was running.