Car making tapping/knocking sound at idle

[b2nvs2001]

Hiya,

Wonder if you could help me?

I recently noticed (yesterday night) that my car makes a tapping or knocking sound at idle.

This sound occurs after about 1 min or 2 mins at idle and happens, as far as I can tell so far, at random. I have heard it twice or three times now. Usually, you can't hear it when the windows are up but I had the windows down yesterday and I could definitely tell there was a tap/knock. It definitely is not a soft tapping as with most direct injection cars of today. It is something else.

I think that it may be the wastegate as some 335i owners have complained about in the past. I really hope it isn't a real "knock" or something really detrimental to the life of the engine!

Could you guys help me? I'm definitely taking it to the dealers but was wondering any of you had some insight.

Thanks.

[Monterra]

There is a rather pronounced tap/clap noise (single) on start up and shut down. Its an exhaust flap opening/closing. Its kind of annoying but if that's what you're hearing there's no need for alarm or even alert

[Robert]

There is a clunking or rather loud ticking noise at idle after start up. I think this is normal but what is odd is sometimes when I am sitting at a light I feel a surge in the engine. Not a lunge forward because i have manual but it almost feels like fluids in some tube was held up then broken free.

[FOXYCaymanS]

Originally Posted by Robert

There is a clunking or rather loud ticking noise at idle after start up. I think this is normal but what is odd is sometimes when I am sitting at a light I feel a surge in the engine. Not a lunge forward because i have manual but it almost feels like fluids in some tube was held up then broken free.

I have the same thing- like it wants to lunge forward and a soft gargle noise... Have been driving on it for a year now.

(Subscribing).

[b2nvs2001]

so guys this clunking, does it come on and off?

I have heard it while idling for a sustained period i.e. 3-4 mins. Once I rev it goes away and then comes back again after 2-3 mins approximately. And then it disappears sometimes.

[imdanomite]

^^i've had this since i bought my car back on 12/12/08. i'm going to be submitting a PuMA case in sometime this week and see what the guys have to say about it. we've been replacing N52 and N52K cylinder heads like crazy for the same exact tapping/knock noise. the manufacturer who built the heads said it didn't need a check valve for the hydraulic lifters. needless to say, they were wrong!! maybe it's the same situation with the N54 motor. i'll post up a thread regarding this issue once i hear from BMW...stay tuned.

[b2nvs2001]

Thanks for your help imdanomite.

So, crap so it could be cylinder heads! F'ing awesome. What does that involve?

So can I still drive my car around for the next week?

[imdanomite]

*small update* so PuMA is asking for a picture of the stamping above cylinder 3 exhaust port. this usually means they're going to authorize replacement with an updated head!! funny...

head replacement involves alot! especially with this motor. bunch of seals have to be replaced, injectors have to be installed/removed in a specific manner, turbos have to be removed, etc. etc....a lot of freaking work for a stupid noise. it really isn't worth the time the car is down and the possibility of something going wrong.

you don't have anything to worry about, there isn't anything mechanically wrong with this. it's just a little noisy. i personally will not be replacing the head on my own car, you can forget about that idea. the ticking noise is something i can live with, not worth tearing apart a brand new motor. now, i may do this job towards the end of my warranty...but we'll see around that time.

but, if you feel like a head replacement is the only way to keep your sanity, by all means, go ahead. your 1er is covered under warranty afterall!!

to be continued....

[b2nvs2001]

Just to clarify, this is for your N52 though right?

So, this may not be the case with the N54

[Midgad]

been discussed b4.
Mine did same, most notibly in winter. Now that warmer weather is here no more taps!!

[tbird]

This has been brought up on other threads. I of course had the issue with the HPFP, so when I took it it, it was the first service, so I had them put on the work order to check the cylinder heads for the ticking issue, even though I was not having it.

Report back stated "Not applicable to vehicle. N54 not experiencing issue". Service guy said that it was the N52 engine having the issue.

If it is the N52 engine in your car, then you have the issue, and supposedly there are official "BMW-workaround" cylinder heads that the dealer will put in. But you should do your research into this. I only offer a broad topic, since I asked about it, and I also heard recently a couple of 328i's go by and they were ticking so loud it sounded like a bunch of elves were whacking the engine block with multiple little hammers. Quite annoying.

Sorry to hear that the 128 drivers are having this issue. Good luck to all, I hope it is eventually fixed satisfactory.

[imdanomite]

no, i am referring to my 135i N54 motor. i'll try to get an update from PuMA tomorrow.

i am very aware of the N52 and N52K situation, i've replaced 4 cylinder heads within the past few months.

[b2nvs2001]

any updates imdanomite?

[BlackjackMulligan]

I guess this issue makes the HPFP issue look good in comparison

[HachiNi]

this is off topic but i got my car from eastbay bmw too

[b2nvs2001]

Originally Posted by HachiNi

this is off topic but i got my car from eastbay bmw too

cool! lol

[imdanomite]

working on the updates...i haven't had time to take my car apart to take pics for BMW. i am waiting for their response as i'm typing this.

**ok, they want me to trouble shoot this a little more (i don't see how). i'll try to take some oil pressure readings on cold and hot. that was a waste of time...

[TechNoir]

Hi folks,

Long time lurker on the site but finally registered just to chime in on this thread.

I've had my 135i (Coupe, 6 speed MT) for a little over a month now and have been noticing a metallic clicking /clacking sound coming from the rear of the car. It is most evident while in 2nd gear and only turning left!

I brought it in for a road test with a BMW service advisor and the clicking sound was easily duplicated by going around in circles (turning left) while in second gear. First gear no clicking and turning right did not produce the sound either.

The Service Advisor pointed out that the sound was coming from a flap inside the muffler which is electronically controlled by the car's computer to moderate the exhaust system for ideal performance. He says it only happens in 2nd gear because it needs more throttle for the vacuum or something to that affect. However he was not able to explain why it only happens while turning left. According to him, this is a common sound from all BMW's ever since BMW started using the vacuum technology for thier exhuast system back in early 90's.

The sound is quite horrible and just does not sound right! If I can try to describe the sound, it almost sounds like a piece of metal which has broken off the axel and is being dragged and bounces off the road and hitting the car. Even with the explanation from the Service Advisor that this is common, my mind is still not at ease so I have scheduled another road test with a different BMW dealership for a second opinion.

If someone can verify if their 135i does this while in 2nd gear going around in a circle turning left, then perhaps we can at least see how much credability there is in the claims of this Service Adisor I spoke to.

Originally Posted by b2nvs2001

Hiya,

Wonder if you could help me?

I recently noticed (yesterday night) that my car makes a tapping or knocking sound at idle.

This sound occurs after about 1 min or 2 mins at idle and happens, as far as I can tell so far, at random. I have heard it twice or three times now. Usually, you can't hear it when the windows are up but I had the windows down yesterday and I could definitely tell there was a tap/knock. It definitely is not a soft tapping as with most direct injection cars of today. It is something else.

I think that it may be the wastegate as some 335i owners have complained about in the past. I really hope it isn't a real "knock" or something really detrimental to the life of the engine!

Could you guys help me? I'm definitely taking it to the dealers but was wondering any of you had some insight.

Thanks.

[No234]

You know what was wierd, I hear the same noise on my car on and off and after like 2 or 3 minutes of idling and this morning I heard it again im wondering what this is, keep me updated please. Thank you

[Maine1]

TechNoir,

Another possibility for the noise you are describing is the thin metal brake dirt shield on the wheels. I had one in back that had warped and would make some annoying noise while turning. I straightened it by hand and it snapped back into shape and has been quiet since. I have seen a few others post that their shield attachment bolts were loose, causing a similar noise.

[jeremyc74]

Originally Posted by TechNoir

Hi folks,

Long time lurker on the site but finally registered just to chime in on this thread.

I've had my 135i (Coupe, 6 speed MT) for a little over a month now and have been noticing a metallic clicking /clacking sound coming from the rear of the car. It is most evident while in 2nd gear and only turning left!

I brought it in for a road test with a BMW service advisor and the clicking sound was easily duplicated by going around in circles (turning left) while in second gear. First gear no clicking and turning right did not produce the sound either.

The Service Advisor pointed out that the sound was coming from a flap inside the muffler which is electronically controlled by the car's computer to moderate the exhaust system for ideal performance. He says it only happens in 2nd gear because it needs more throttle for the vacuum or something to that affect. However he was not able to explain why it only happens while turning left. According to him, this is a common sound from all BMW's ever since BMW started using the vacuum technology for thier exhuast system back in early 90's.

The sound is quite horrible and just does not sound right! If I can try to describe the sound, it almost sounds like a piece of metal which has broken off the axel and is being dragged and bounces off the road and hitting the car. Even with the explanation from the Service Advisor that this is common, my mind is still not at ease so I have scheduled another road test with a different BMW dealership for a second opinion.

If someone can verify if their 135i does this while in 2nd gear going around in a circle turning left, then perhaps we can at least see how much credability there is in the claims of this Service Adisor I spoke to.

A lot of us have that noise. Another member took his car in and they found a loose brake shield that was rattling. Mine used to do it only at higher speeds, but now it's doing it at parking lot speeds, so I'm going to have it looked at when I take the car in for service.

[kb2dhg]

It seems like there are a lot of problems with the 135's? I have a 128i and don't hear any complaints about noises or bad fuel pumps? Anyone out there with 128i problems?