secondary air pump and whining noise on cold start ups?

[jskin1510]

hey my secondary air pump i think was bad every since i bought my car but the other day i finally installed one that i had bought used and now whenever the car is cold and i start it up for the first probably two mins or so of driving and it makes this humming, winding sound. i poped the hood today when it did it make sure it was the air pump and it def is and you can feel the air pump vibrating. is this normal or is it just new to me because now it works? thanks.

[mzmtg]

A soft vacuum-cleaner-like sound is normal.

[bjm442]

i had bought used and now whenever the car is cold and i start it up for the first probably two mins or so of driving and it makes this humming, winding sound.

You bought a used one. You can get a new one for $260.

I'm replacing mine right now.

[CT Sean]

I installed a brand new one a few months ago and it's dead quiet. When you took the thin plastic hose off the top, was it wet inside? If so your new one will die sometime too.

[bjm442]

the secondary air pump will be the last thing to go bad. You need to replace the VALVE!!

[nighthawk328i]

Yeah +1 on the control valve. I both air pump and control valve for my car. Turned out the air pump was fine and it was just the valve and there was no water in the pump so now i have a brand new secondary air pump that i have nothing to do with.

[jskin1510]

i replaced the egr/check valve at the same time as the pump both are used. and i got them both for like 105 shipped total that's why i didn't pay $260 for a new one. i checked the plastic hose and it wasn't wet at all, so i guess that's good. what is the chance that my old pump wasn't bad and that my check valve was the only thing bad? should i try installing my old air pump with the newer check valve and see what happens?

[bjm442]

thats what I would do

[jskin1510]

bump

[cab354]

Mine makes a quiet whistle type noise on very cold days (sub-freezing temps), only when I'm accelerating.

My mechanic said it's normal..

[jskin1510]

bump i know it's been a while but i was still curious about this

[Entropyman]

If you get the Bav Auto newsletter, they have a complete troubleshooting guide on the secondary air system in this month's issue.

[Bris328is]

replace the valve and pump

[cab354]

Why would you bother replacing it?

the only time it's on is when it's very cold, and all it does is cut down on emissions when it's cold..

[Entropyman]

I believe that someone on here with much more experience than me said that a properly functioning secondary air system helps keep the cat(s) working properly.

[gdeangel]

I had problems with my secondary air pump and control valve that turned on the check engine light.

Here's what I found:

- Check the air pump right after starting the engine and make sure it's running (you can hear it). If not, the problem is most likely the pump, but maybe the relay.

- Even if the pump is running, it is mounted using rubber bushings that can fail. Mine did, and you can get replacements at any good hardware store.

- The valve that directs air to the exhaust can get stuck for a couple of reasons. 1st the vacuum line can be bad, and also you may need to take the valve off and clean it (carb cleaner) to get it to open properly.

Hope this helps

[choffa]

The key words here are "bought used" Used parts are always crap shoot as to their condition. If the noise sounds like a police siren, it's gettign ready to fail. A vacuum cleaner noise, let it run until it craps out. If the noise is objectionable, buy a new one.

[Malcolm]

Why would you bother replacing it?

the only time it's on is when it's very cold, and all it does is cut down on emissions when it's cold..

If you live in an emissions inspection state, you don't have a choice. You can't pass with a check engine code set.

[Entropyman]

Just for general reference here is my troubleshooting so far:
-Disconnected hose from shutoff valve to SAP and started cold engine, result- good airflow and quiet pump
-disconnected vacume line from shutoff valve and connected a vacume guage, result- no vacume when cold engine is running
-disconnected electrical connector from vacume control valve and checked with a voltmeter after starting cold engine, result- good (13.8) voltage at connector.
-disconnected vacume input hose from vacume control valve and connected vacume guage, result-no vacume with engine running.

More troubleshooting is to follow. The reason I posted all this is to illustrate that it is important to thoroughly troubleshoot this system before buying a bunch of parts. This may end up being a clogged check valve, a $7 part.

[cab354]

If you live in an emissions inspection state, you don't have a choice. You can't pass with a check engine code set.

Ah I didn't notice that the OP had a CEL on

[Grogu]

Bump

Instead of starting a new thread I figured I would bump this. I have a similar loud noise on cold start for a couple of minutes. Its loud enough to hear it a few doors down too. I know it coming from the SAP/hose. I installed a new SAP from Uro and this happened. Mind you my car was literally not started for 1 full year and 1 month or 2 months. So about 13-14 months no start. I put in a new battery, new spark plugs, new coil packs, new valve cover gasket, new pre-cat 02 sensor (the one near ABS Module). Everything is running fine and no codes but I will check again.

The only other problem is I have the Traction Control light on the dash on permanently and that was never an issue before. On this, on one drive I got it to go off with the DSC button, but most the time the button won't work and it stays on the dash.

Any help would be greatly appreciated.