What is this engine noise? 2000 528i - video link

[bison]

Hi - newcomer to this forum here. I have a 2000 528i with about 120k miles on it. Recently I've been hearing an odd noise from the engine compartment that sounds like a bunch of crickets. See link below. It's hard to localize, but if I had to guess it would be coming from the front drivers side, near the power steering fluid reservoir. It appears to be most noticeable at idle and disappears when the engine is revved up a bit. I'm guessing it's something associated with the engine belt. No other unusual symptoms such as leaks or otherwise. Would appreciate any help - thanks!

Odd noise in 2000 BMW 528i - YouTube

[Dave M]

My 2 cent guess =belt pulley bearing. You could test this by spraying individual pulleys with a lubricant. Try not to soak the belt while you're at it.

Good luck with it,

Dave

[shogun]

is that engine with VANOS. Is the noise only when you start the engine cold?
Then it could be the famous tin can rattle of a defective check valve or the secondary air pump is defective, or the hose between secondary air pump and the check valve is brittle and damaged.

I had the same, here copied from some months ago (excerpts):

VANOS Rattle Noise After Engine Start E36 M3 2/1998
since some time I have a rattle like marbles in a tin can when starting the cold engine, very short time, when I rev a bit, the noise is gone. No problems with performance, no CEL, nothing to complain. 32 k miles only on the 1998 M3 with S52B32.
Not sure yet if it could be vanos or something else, by checking with a screwdriver as mechanic's stethoscope I had the feeling the noise comes from the vanos area. But it could be also a pulley bearing or something like that.

Now I found this:
MODEL E39 M5 and E52 Z8 with S62 engine produced up to 11/30/00.
SITUATION: A rattling noise coming from the front of the engine (VANOS area) may be heard for a few seconds after start up.
CAUSE: The VANOS adjusting units may cause a momentary rattling noise after the engine is started due to varying torque of the camshafts before sufficient VANOS adjustment oil pressure is built up. When the engine is switched off, oil bleeds out of the high-pressure chamber in the VANOS adjustment cylinder. This can cause the VANOS adjustment piston to move freely against the housing during engine start up causing the momentary rattling noise.
This noise has no effect on engine power output or durability.
CORRECTION M5 and Z8 vehicles produced from 12/1/00 incorporate a VANOS accumulator shutoff valve which prevents oil bleed off of the high-pressure chamber after the engine is switched off.
On a customer complaint basis only, a VANOS accumulator shutoff valve can be installed to eliminate the momentary rattling noise after the engine is started on vehicles produced before 12/1/00.

http://www.bmwz8.us/pdf/Z8_VANOS_s62.pdf

BMW E36 Secondary Air Pump and Non-Return Valve Replacement

Vehicles:
1996 and up U.S. E36 323i/328i/M3.

Symptoms:
1. A Check Engine light that returns the fault codes F5 and F6. These codes indicate that the secondary air flow system is too low for cylinders 1-3 and 4-6, respectively.

2. Before the Check Engine light comes on, you will likely notice a whining, scraping, screeching, whistling or groaning sound coming from the passenger side of the engine compartment. The noise begins immediately after a cold start and stops after a minute or two.
Problem:
The secondary air pump has failed due to moisture inside the pump.

Solution:
Replace both the secondary air pump and non-return valve.

Background on the Secondary Air Pump
The secondary air pump, located near the firewall on the passenger side of the engine compartment, draws air from the engine compartment and injects it into the exhaust manifolds to provide extra oxygen to the catalytic converter and reduce cold start emissions. A non-return valve mounted on the exhaust manifolds normally prevents exhaust gases from flowing back into the pump. When the non-return valve fails, moisture in the exhaust gases accumulates in the pump, causing it to eventually fail.

This pump normally sounds like a vacuum cleaner under the hood, and it only operates for the first couple of minutes after you start the car. It will not leave you stranded if it should fail. You can replace the parts at your leisure, unless you have an emissions inspection coming up.


The F5 & F6 codes are indicating that the secondary air injection system is not functioning properly. This system injects (pumps) air into the exhaust manifolds during a cold start. This is intended to supply additional oxygen to promote a more complete burn of the outgoing exhaust gasses, during the initial cold start and warm-up phase. Failures of this system are quite common. The typical failure is that the check valve that is mounted on the exhaust manifold fails in the open position. This allows exhaust gasses to run back up to the pump, when the pump is not running. This eventually destroys the pump. Therefore, you typically have to replace both the check valve and the pump. The remainder of the system is comprised of the pump to valve hose, vacuum hoses, an electrical vacuum control switch and a fuse and relay. There is the possibility that any of these other areas that control the pump and the check valve could have faults as well.
F5/F6 is the same you found on your car as P1421 and P1423. F5/F6 is the code you get when you test with a Peake fault code reader.

After studying the whole thread I investigated further. So the pump is repairable.
See here

YouTube
BMW SMOG PUMP REPAIR - YouTube
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.

rebuiltairpump dot com

Quote:
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

I have not bought the part from this company, but the price of $139 is not bad, unless one tries to repair DIY, what I will try
How To Test A BMW Smog Pump Air Injection Check Valve
How To Test A BMW Smog Pump Air Injection Check Valve - YouTube

technical information
http://motorvate.ca/bmw/BMW_Secondar...em_Failure.pdf


pics
and explanations on codes P0410, 0411, 0412, 0415, 0413, 0416, 0414, 0417, 0418, 0419
http://www.ms-motor-service.com/xima...969-02_web.pdf

Quick inspection of secondary air valves
http://media.oscaro.com/pdf/5/pg_si_0083a_en_web.PDF

aftermarket products overview
http://www.wilmink.nl/pierburg/Pierb..._luchtpomp.pdf
Pierburg 7.21852.85.0 = BMW E36 Compact p/n 1744490, 11721744490

[bison]

Shogun - thanks for the idea, but it isn't just on startup. If anything it's louder after it warms up, so I think it's something else.

Dave - good idea, I'll try to get in there with a can of WD-40 this weekend.

[ScottyWM]

Agree with Dave, sounds like a bad pulley I had once. They're cheap, at your mileage you should do it all, belt, pulleys, tensioners - if it hasn't been done yet. Water Pump too while you're there!

[bison]

Thanks - any idea if I can find some guides to how to do this on the web and/or specifics about what to replace? I'm fairly handy but am not very familiar with this engine. Also any recommendations for good sources for parts other than my local dealer?

[Dave M]

Thanks - any idea if I can find some guides to how to do this on the web and/or specifics about what to replace? I'm fairly handy but am not very familiar with this engine. Also any recommendations for good sources for parts other than my local dealer?

Yep, find Bentley manual, hardcopy or online. Te most difficult part of replacing belts/water pump on the M52 is removing the frigging fan shroud on your way to the fan clutch. In order to fascilitate easier removal (especially for the inevitable future jobs), I recommend cutting the shoud in half (horizontally) and zip-tieing or otherwise connecting it together. I works a charm and its hard to even notice if you do a good job drilling small holes for the zip ties and use black ones. The easy part is replacing the belts.

Dave

[shogun]

instructions here BMW TIS Online • 5' E39 • 528i (M52) Saloon • Engine • V-ribbed belt w.tens./deflect.elemt

[bison]

OK thanks for the help. I'm pretty sure it is indeed one of the pulleys as there are some other youtube videos of bad pulleys with the same sound. A few questions:

- Seems like I should replace the set. Am I right that this is the tension pulley and idler pulley for the main belt and tension pulley for the a/c belt?
- Any reason to replace the water pump pulley? Doesn't look like there's much to go wrong with it.
- Do I need the special tool to hold the water pump while I get the fan clutch off? Looks like a 1 1/4 wrench will work for the fan nut. I see it's a backwards thread.
- Scotty suggested replacing the water pump as preventative maintenance. Is this recommended? Car has about 120k miles and I don't believe has ever had a new pump.
- Should I get parts from my local dealer, Autozone, or on-line?

thanks! Looks like a fun project for the weekend.

[genphreak]

OK thanks for the help. I'm pretty sure it is indeed one of the pulleys as there are some other youtube videos of bad pulleys with the same sound. A few questions:

- Seems like I should replace the set. Am I right that this is the tension pulley and idler pulley for the main belt and tension pulley for the a/c belt?
- Any reason to replace the water pump pulley? Doesn't look like there's much to go wrong with it.
- Do I need the special tool to hold the water pump while I get the fan clutch off? Looks like a 1 1/4 wrench will work for the fan nut. I see it's a backwards thread.
- Scotty suggested replacing the water pump as preventative maintenance. Is this recommended? Car has about 120k miles and I don't believe has ever had a new pump.
- Should I get parts from my local dealer, Autozone, or on-line?

thanks! Looks like a fun project for the weekend.

Last time this happened to me, it was the tensioner pulley only.
Check to remember the way you need to thread the new serpentine belt back- doing a little sketch is a good idea before removing it.
Best to replace all, beware dust caps as they are important- if any are missing you will have to buy new ones.
Water pump should be done, unless you are happy to come back and do it again, unless you know its been replaced before (keeping a spare is a good idea if you aren't). Probably a good idea to drain and replace all fluids- making sure you have Super Dot 4 and the right oils and coolant. Be sure to do a full drain of the radiator and block as per the TIS.

Enjoy your wrenching time!





Best place to get ur parts is bmaparts.com