Please help me identify another MCS engine noise.

[tenderidol]

My car was at the dealer last week. My PCV hose was replaced along with my clutch. After picking up the car, now there is another noise coming from the engine. It was definitely not there before, since there is no way to "ignore" this...

Here is the description of what I have now:

When I rev up to 3-4.5K rpm (at any gear) and release the throttle, an engine noise appear. It is very loud and noticeble and it sounds like a vacuum type noise, but I may be wrong on the description. Higher the revs that the engine is coming back from, louder the noise gets. If I just touch the gas pedal and release it again, while the rpm is going down, it stops accordingly and continues again. If I am cruising around 70 mph, while pushing the gas pedal little bit and releasing it to keep the speed constant, it follows the cycle of throttle "push and release". Also, if I push the clutch while the noise is present it disappears (when I release the clutch it comes back). It does not occur when the car is in iddle - only while in motion.

Is this something related to the PCV (or crankcase) hose replacement? The noise is different from what I had before with the defective PCV hose (that moaning type noise). Note that my clutch was also replaced during the same visit, if that helps to rule out some stuff.

Thanks in advance for all the help and suggestions!

[bkwalker]

my suggestion would be to take it to the dealer and get them to fix it up

either way, it sounds like you will need to go there anyway..

i've never heard of this sound anywhere... it's possible it could be causing damage also

[tenderidol]

I already made an appointment for this, but it wont be another 10 days. I just wanted to gather as much information beforehand to have an idea about the source of this noise. It helps me keep my sanity and enjoy the ride
For instance, if this is still something related to the PCV hose, etc, I will not worry about that much driving the car around. On the other hand, if this is related to the recently replaced clutch and any related components, then I will hate killing the car at each mile I drive around... Just trying to sort this out.
In any case, I am stopping by the dealer tomorrow to have this looked at (with an appointment or not!!!!).
Thanks.

[bkwalker]

mmm good idea.

its under warranty though! so no matter what the prob is, it'll be fixed

i remember when i first got my car, i had a problem, there was a leak in my power steering oil thing... anyway, i told the dealer and they said to top it up with oil (CHS11F i think the oil is called)... so i topped it up till i saw the dealer ... but this never ended up working and they had to replace the whole power steering RACK! all because they let me drive around all week...

SO, i would be careful... but the dealer will cover it either way

(depends how nice you want to be to the dealer and your car!)

[tenderidol]

Well... I stopped by this morning. They were buried and understaffed for Friday (Halloween weekend). I was told to bring it back Monday for a test drive with the technician, who installed the new clutch. We'll see how that goes.... In the mean time, I am using "neutral" as my preferred gear, since the engine does not make any of those horrible noises while crusing in neutral. Gotta love the MINI

[MrSpaz]

Hmm...you say "vacuum noise," which I assume means a hissing sort of sound. Since it doesn't happen in gear and disappears when you engage the clutch, I wonder if maybe you're actually hearing parts of the clutch rubbing together. Might be a throwout bearing that's not retracting all the way staying in contact with the leaf springs or holding the clutch plate just slightly off the flywheel. Is there any noticeable power loss? Does it shift differently (either staying "grabby" between gears or not seeming to catch completely after a shift)?

The fact that it doesn't happen in neutral is kinda tricky, since the problems I described (if audible) should happen with the clutch out no matter what gear you're in, unless it is the plate slipping in which case it might not be doing it without load on the layshaft.

[tenderidol]

Thanks for your reply.

Yes... the noise when the throttle is released sounds like a hissing noise. I dont know too much about engines to speculate which of your suggestions may be true. No, there is no loss of power or shifting differently; just a lot of noise. There is also a noise at the low RPM range (0.8-1.5 K). If I dont give too much gas when taking off (1st gear of course), the engine sounds like a "diesel" engine; too much clicking. Same thing happens if I move to 2nd gear relatively early and let it cruise around 1.5 RPM. I know that there is a tapping noise when in high gear/low RPM, but this is at least 20X more than usual if that means anything.

[MrSpaz]

Well, the way you describe it I'd go with the throwout bearing. Often when they start to fail you get a relatively loud "grumble" from the drivetrain; since you say it sounds like a diesel I'm guessing that's what's going on. What's strange is that your dealership just replaced the clutch, they should have done the bearing at the same time. Maybe it just didn't get installed properly.

Keep us posted on what happens. I'd like to see just what the dealership finds out when they get in there.

[tenderidol]

Thanks! During the test-drive on Monday, I will pretend to know and say "it sounds like throwout bearing to me" Hopefully he wont ask more....
Come to think of it, the engine click at iddle -which goes away when the clutch is depressed- also seems to be higher than normal. This is also throwout bearing related, right?
Thanks again!

[tenderidol]

Alright... I went to dealer today and did a test drive with the person who installed the clutch. I demonstrated him both the "low RPM ticking noise" as well as the "high RMP -when throttle released- hiss noise". He agreed that the engine is very noisy and it may be either gear noise or something with the transmission. I did mention the "throwout bearing" and he said it may also be the reason, but they would not know until they look at it first... well, there lies the problem: they cant look at it today since there were millions of car there this morning. In addition, apparently they stopped their "loaner car" program -as of today- and I have to rent a car and take my MINI to service VERY early tomorrow morning to have a chance to get it looked at... It's a "non-appointment" deal, even though they messed things up and did not install it properly to begin with. Anyways... instead of creating problems, I agreed to bring it tomorrow and rent a car for a day. It kills me to think that I am doing something to the engine with every mile I drive it...
I will post updates once anything new happens to help people having a similar problem....
Thanks!

[tenderidol]

4 days after dropping the car for a service, I just received a called saying my car is ready.
I talked to the tech, who originally replaced the clutch and has been trying to solve the noise issue. Apparently, it was the "low transmission fluid" that caused the noise I described above. He drained it and collected 1.2 L (as opposed to 1.5 L). He said the clutch is normal and the "gear noise" went away after adding new transmission oil (full amount).
Well... I am not holding my breath yet. Let's see how it is after I test drive it
Thanks for all the help!

[MrSpaz]

Cool. Hopefully that will fix your problem. Good luck out there.

[tenderidol]

Thanks. All the noise is gone after the "transaxle oil" replacement. There is still something "funky" with the clutch, but I cant put my finger on it yet. I am sure it will show up somewhere if something is not right in there...