[jase71]

Hey Guys,

I've had my 325i for a couple of months and have done around 2900 miles. I love the car but am surprised how rattly or diesel sounding the car is at idle. It just sounds tappety all the time cold or warm. My dealer says its due to the new 6 cylinder engines lean burn cycle at idle. Peformance is good but just surprised at noise, might as well have gone for the diesel!

Any similar experiences? Is this normal?

[dxb335d]

Compare with another one mate, get the dealer to bring one out the showroom and start it up!

[jase71]

Yeah, will try but just need to find the time at the moment.

[jjbirch]

hope u got it sorted m8 i think a 325i should sound quite smooth really with a nice 6cl noise

[Alex1974]

I think a slightly rattly idle is just a characteristic of direct injection engines. Mine certainly has it, but still much much quieter than a diesel.

Once up to speed it should be as smooth and 'zingy' as you expect from a Bimmer straight six though - as others have said, listen to another car for comparison.

[-=TSL=-]

jase71,

I have the same engine as u, and mine also does have a tapping noise from the engine at idle..

But it stops when u get moving! Im guessing thats just the way its supposed to be! I was thinking of getting it checked, but it seems im not the only one!


TSL

[Z4 Beemer]

My engine is actually the older style 6-in-line 2.5i, but yes, it does sound a bit tappety at idle. At speed it sounds just fine.

[M3-FAST]

Mine does this also - the regular BMW tech who came out a few times (when the steering and fuel pump failed I think, lol) said it was down to the new high pressure piezo injectors and not to worry about it.

I must admit I was sceptical and asked the dealer to listen to it. They came back with exactly the same response.

A couple of my mates have commented how tappety it sounds - very strange for a new engine. Maybe there should be some under bonnet sound insulation to stop some of the noise?

Paul

[-=TSL=-]

Originally Posted by redE93cab

Mine does this also - the regular BMW tech who came out a few times (when the steering and fuel pump failed I think, lol) said it was down to the new high pressure piezo injectors and not to worry about it.

I must admit I was sceptical and asked the dealer to listen to it. They came back with exactly the same response.

A couple of my mates have commented how tappety it sounds - very strange for a new engine. Maybe there should be some under bonnet sound insulation to stop some of the noise?

Paul

True, not the nicest sound in the world! Sounds remarkably like a diesel at idle (not a bad thing)


TSL

[Z4 Beemer]

I think it does sound a fraction worse when the engine is cold. Best to just Start and drive immediately to avoid anyone nearby from hearing it, especially when in a car park!

[jase71]

Cheers guys, don't feel so bad now! It's my first BMW and I'm really enjoying all other aspects of ownership. The car handles great and feels like it's really well built. It's also practical enough to take my 11 month old in the back who smiles every time I put the foot down!

[M3-FAST]

If you leave mine ticking over, the noise does stop - it is strange, not sure after how many minutes, but it suddenly becomes noticably quieter. Almost as though somone flicks a switch!

Do the other 325i guys engines do this also?

[-=TSL=-]

Yeh it does stop sometimes.. was in traffic the other day and had the window down, and all was well!

Then I required some aural stimulation, and revved only to bout 2500, and it started again!! WAAH!

TSL

[the_oracle1980]

Yes Guys

This is perfectly normal on the new 325i Engine, the engine goes into strafied mode at idle and overun. Basically 40 parts air to one part fuel, and normal driving 13-14 parts air to one part fuel. The noise your hearing is basically combustion and injector noise because its running so lean in this mode, you can almost say running on air

[jase71]

Thanks mate, so my local BM dealer was telling the truth!

[weez]

I had a 325i loaner for about a week and was surprised at how much it sounded like a diesel at idle. My 328i is much quieter at idle. Both silky smooth when you put the pedal down, but the 325 could use a few more hp.

[NFS]

This may not be the same thing, but the pre-DI engines also suffer from a metallic ticking noise at idle from a very cold start. It doesn't sound like a diesel, but it does sound like the tappets.

I have particularly noticed this on my car after 3-4 days where the car is only used for very local journeys.

If I have a good run in it, at least 20 miles, the noise vanishes and will not reappear for a week or so.

There is a very scary thread on the forum about the metallic ticking noise, but my experience is that it's simply related to the way you drive. On a longer run, with some enthusiastic revving, the engine runs brilliantly, but if you drive it in the town and don't give it some beans it starts to tick.

The dealer said the same, advising that it's related to the oil level near the valve rockers and normal for extreme cold starts. They did something to bleed the system when it had it's last service and the noise has disapeared almost entirely now.

They also made a note on the service report saying that I should 'drive more enthusiastically'

[dxb335d]

Originally Posted by redE93cab

If you leave mine ticking over, the noise does stop - it is strange, not sure after how many minutes, but it suddenly becomes noticably quieter. Almost as though somone flicks a switch!

Do the other 325i guys engines do this also?

Sounds like some sort of oil pressure problem. If it was injectors or something clicking open it would always be there. HMM another e90post investigation is on the cards me thinks!

[weez]

Originally Posted by needforspeed

This may not be the same thing, but the pre-DI engines also suffer from a metallic ticking noise at idle from a very cold start. It doesn't sound like a diesel, but it does sound like the tappets.

I have particularly noticed this on my car after 3-4 days where the car is only used for very local journeys.

If I have a good run in it, at least 20 miles, the noise vanishes and will not reappear for a week or so.

There is a very scary thread on the forum about the metallic ticking noise, but my experience is that it's simply related to the way you drive. On a longer run, with some enthusiastic revving, the engine runs brilliantly, but if you drive it in the town and don't give it some beans it starts to tick.

The dealer said the same, advising that it's related to the oil level near the valve rockers and normal for extreme cold starts. They did something to bleed the system when it had it's last service and the noise has disapeared almost entirely now.

They also made a note on the service report saying that I should 'drive more enthusiastically'

I think there's a BMW service bulletin recommending bleeding the system as a cure for the ticking. The bulletin also states that its not detrimental to the engine. Though that isnt too reassuring to me. I think it has something to do with oil pressure not properly reaching the head when cold and the lifters making the noise when the engine is cold due to lack of oil. Though most with the problem said it reappeared even after the bleed. The main problem I think is that its intermittent and seems to go away when you bring it to the dealership Thus the dealership calling it normal.
Ive heard it on my car once before which lead me to search the forums. It worries me, despite BMW's service bulletin. Though it seems common enough that by now if there was a serious problem we'd see some catostrophic failures.

[dxb335d]

Originally Posted by weez

I think there's a BMW service bulletin recommending bleeding the system as a cure for the ticking. The bulletin also states that its not detrimental to the engine. Though that isnt too reassuring to me. I think it has something to do with oil pressure not properly reaching the head when cold and the lifters making the noise when the engine is cold due to lack of oil. Though most with the problem said it reappeared even after the bleed. The main problem I think is that its intermittent and seems to go away when you bring it to the dealership Thus the dealership calling it normal.
Ive heard it on my car once before which lead me to search the forums. It worries me, despite BMW's service bulletin. Though it seems common enough that by now if there was a serious problem we'd see some catostrophic failures.

Not really mate, would take a while before any real probs surfaced.

Like after 50-60k of this issue you might have a real rattly head. But if its ittermittant it can take a while for any real serious failure.

Shame as the next few owners may end up with issues on these cars which is not good for BMW's reliability image.

[weez]

Originally Posted by dxb335d

Not really mate, would take a while before any real probs surfaced.

Like after 50-60k of this issue you might have a real rattly head. But if its ittermittant it can take a while for any real serious failure.

Shame as the next few owners may end up with issues on these cars which is not good for BMW's reliability image.

Well I guess we could take the valve cover off and inspect the head. Some early E9X models should be approaching 50K by now. At least before my warranty runs out we should have more insight. If I see major problems my car will be going to dealer ASAP.

[NFS]

Originally Posted by weez

I think there's a BMW service bulletin recommending bleeding the system as a cure for the ticking. The bulletin also states that its not detrimental to the engine. Though that isnt too reassuring to me. I think it has something to do with oil pressure not properly reaching the head when cold and the lifters making the noise when the engine is cold due to lack of oil. Though most with the problem said it reappeared even after the bleed. The main problem I think is that its intermittent and seems to go away when you bring it to the dealership Thus the dealership calling it normal.
Ive heard it on my car once before which lead me to search the forums. It worries me, despite BMW's service bulletin. Though it seems common enough that by now if there was a serious problem we'd see some catostrophic failures.

Yes .. this is the problem I have experienced.

I don't honestly think it will be that damaging, but I would still not want to run the engine much when this is happening.

The bleed seems to have cured it for me. If it re-occurs, then I'll get them to do it again I suppose.