Engine bay Buzzing

ms.smally · Post by **ms.smally** » Sat 27 Mar, 2010 15:18

Hi

I have an annoying buzzing sound that comes from the engine bay when the keys are turned to position one and lasts for a minute or so after you turn it back. It doesnt seem tohappen when the engine is running.

Having had a good look round, I have traced the noise to the electrical componant next to the TPS, but I dont know what it is!

That is definately the part that is making the noise, it gets warm and vibrates whilst doing it and the noise stops if you pull out the electrical connector in the bottom.

Can anyone let me know what this part is and why it might be buzzing?

Thanks

Mike Fishwick · Post by **Mike Fishwick** » Sat 27 Mar, 2010 16:32

Probably the cooling fan for the box containing the ECU etc - it draws air from, and exhausts it to, the area above the throttle pedal.

Frank.A · Post by **Frank.A** » Sat 27 Mar, 2010 20:02

From what I have found by Googling around it could be the Idle Control Valve ICV.

When you say key position 1,do you mean ignition on?I call that position 2 with 1 being accessory position.

If I switch to position 2 ignition I hear the buzzing from around the area of the TPS.When I switch off the noise continues for a couple of seconds.

aj2007 · Post by **aj2007** » Sat 27 Mar, 2010 20:06

Hi there

You don't say what car/model you have?

Cheers
Ade

Post by **Robert T** » Thu 01 Apr, 2010 18:32

AFAIK this is perfectly normal - my M44-engine 1.9 certainly does this - it comes from the area around the ICV/TPS.

Cheers R.

Mike Fishwick · Post by **Mike Fishwick** » Fri 02 Apr, 2010 16:10

On my 2.8 there is no noise frm the ICV, but plenty of activity from the fan inside the box containing the ECU etc. It can be heard inside, and felt when you rest a hand on the lid.

Frank.A · Post by **Frank.A** » Fri 02 Apr, 2010 20:24

Everthing that I have read about the ICV states that it will either be heard or felt 'buzzing' with the ignition switched on.

The following is quote from one article on ICV operation.

"Turn the ignition key to run position, but don't start the car. You should hear quiet buzzing sound from the ICV, and if you touch it with your fingers, a vibration. If not, either the ICV is bad or there is no control current."

Mike Fishwick · Post by **Mike Fishwick** » Sat 03 Apr, 2010 08:32

What utter rubbish! My ICV works fine, and does so without making noises when the ignition is turned on. The ECU fan is what makes the noise on my car.

Just because something is written down (Haynes is a good example) or on the internet does not mean it is holy writ.

Make your own mind up about things.

Frank.A · Post by **Frank.A** » Sat 03 Apr, 2010 09:13

Mike,I had already made up my mind with my first post on this subject and everything I have read since confirms what makes the noise on my 2.8,that is apart from your explanation.

I haven't even looked at Haynes!

I agree to differ.

Post by **Robert T** » Sat 03 Apr, 2010 12:07

Well it certainly isn't a fan noise on mine. It sounds like a cross between mains hum and a relay operating very quickly - a sort of clickety-buzzy noise. Fans go whirrrrr.

Turn the ignition to position II, but don't start the engine. The buzz will start and carry on for a couple of minutes before stopping. It is only just audible in the cockpit, but quite a clear noise with the bonnet open.

To my knowledge, the car has always done this from new, so I would say it was normal rather than a fault.

Cheers R.

Mike Fishwick · Post by **Mike Fishwick** » Sat 03 Apr, 2010 12:08

Not that it really matters, but have you tried putting your ear or hand to the ECU box, or near the top of the accelerator pedal?

We have had a couple of ICV-equipped VW Golfs, and daughter had a 318Ti, none of which had noisy ICVs.

I would hazard a guess that the cause of a noisy ICV is likely to be either a sticky valve, or dirt on the pole pieces of the solenoid core - either of which will prevent the pole pieces meeting fully. This is a regular cause of noisy solenoids and relays in industrial systems.

A good cause of a sticky ICV is oil contamination, which will make any dirt stick to the valve. A K&N type air filter will soon shed its oil into the intake trunking, and so get into the ICV. Without oil, the filter loses most of its filtration properties, and passes dirt particles into the ICV, coating it oily surfaces.

Hard Top · Post by **Hard Top** » Sat 03 Apr, 2010 21:54

This, probably, did not make a 'buzzing sound'

HT

http://www.myfoxdc.com/dpps/news/dpgonc ... 01_6861916

Mike Fishwick · Post by **Mike Fishwick** » Sun 04 Apr, 2010 08:14

This kind of thing does happen - while camping in Germany, a friend wriggled into his sleeping bag late one night after a 400 mile day, emerging panic-stricken and naked intothe camp site!

the cause - a 'monster' in his sleeping bag - which turned out to be a kitten which had been seen at the previous night's campsite! It had been asleep in the comfort of his rolled-up sleeping bag, inside a motorcycle pannier all day.

NewZedMan · Post by **NewZedMan** » Sun 04 Apr, 2010 12:31

My 1998 1.9 Z3 makes the clickety-buzz noise but it's never worried me. I used to have a Westfield and the electrical fuel pump made a similar noise while it was pressurising. I just assumed that it was the same sort of thing again.

Happy in ignorance.

Hard Top · Post by **Hard Top** » Sun 04 Apr, 2010 13:24

Mike Fishwick,

Brilliant, but what happened with the kitten?
Did you take it back to the other camp site, or is it now purring away on your sofa?

Cheers, HT.

Mike Fishwick · Post by **Mike Fishwick** » Sun 04 Apr, 2010 16:28

No - it was quite happy to live on the other side of Germany!

Hard Top · Post by **Hard Top** » Sun 04 Apr, 2010 17:02

ok, saved you from have to teaching it French

HT

zroadster.net

Engine bay Buzzing

Engine bay Buzzing

Noise

2.8

Icv

Noise

Cat

Clickety-buzz

Kitten