Did I break something?

[fighting_fish]

I was accelerating hard at high rpms from 3rd to 4th gear and experienced a sudden loss of power. I figured that the rpm limiter had kicked in, except right after I was hit with the smell of burnt breaks.

For the rest of the drive home the car felt different, as if the gear box had more play and the car had less power.

That section of my commute is a downhill where inexperienced drivers ride on their breaks, so it's not the first time I've smelt breaks in that spot. So what I felt could've been simply placebo effect (aka I thought there was something wrong, so it felt wrong). When I got home I popped the hood and didn't see or smell anything out of the ordinary.

Am I a victim of paranoia or could I have broken something?

[AWM3]

Originally Posted by fighting_fish

I was accelerating hard at high rpms from 3rd to 4th gear and experienced a sudden loss of power. I figured that the rpm limiter had kicked in, except right after I was hit with the smell of burnt breaks.

For the rest of the drive home the car felt different, as if the gear box had more play and the car had less power.

That section of my commute is a downhill where inexperienced drivers ride on their breaks, so it's not the first time I've smelt breaks in that spot. So what I felt could've been simply placebo effect (aka I thought there was something wrong, so it felt wrong). When I got home I popped the hood and didn't see or smell anything out of the ordinary.

Am I a victim of paranoia or could I have broken something?

Did you break the brakes? Probably not.
My first guess would be slipping clutch.

[txz4]

clutch for sure. brakes are not a distinctive smeel when compared to the smell of burnt clutch. if anything it sounds like you somehow glazed your clutch, that or its just old and slipping.

[fighting_fish]

Today I drove it and everything seemed fine. Maybe another reason to delete the CDV? In any case, is there anything I need to do, fix, or look at to make sure all is well? Thanks for your replies I really appreciate it.

[txz4]

if you accelerate quickly and the revs climb and the car doesnt speed up than the clutch is about dead, thats about the only concrete thing to look for. Also if gear changing seems much harder than usual that could be an indicator as well. I dont Know much about BMW CDV, but on my evo the CDV was only really a hinderance if you launched it from a stop, if you do that alot, than you may want to remove it (at risk to your drivetrain) otherwise i dont see it being a problem.

[pokeybritches]

A CDV won't slip the clutch enough to cause a smell. If you're smelling clutch it's either your own doing, another car, or something mechanically wrong with your car. If it's driving fine today then you can probably rule out mechanical issues. How long have you been driving a manual transmission?

[fighting_fish]

Acceleration is fine, and gear changes didn't offer resistance. I tested by down shifting from 2nd to 1st at 3.5k+ rpm and didn't have any issues.

As for manual transmission: I drove a stick for the first 10 years of owning a car. After that I moved and didn't have a car for 5 years, and now I've had the Z4 for about 8 months.

[Z4-VILLA]

i have owned a 2.5 before and those things haul ass, however idk about what your talking about never had those issues, actually that motor had less ( excuse me)...way less issues than my 3.2 so have a look at the vanos first and then how many miles to your 2.5?

[Z4-VILLA]

on another note a well tuned and supercharged 2.5 will rape a 3.2...ive done this.

[Z4-VILLA]

take another look around the bottom of the car and if the smell of brakes os stronger than your issues are just a really keen olfactory nerve.

[fighting_fish]

I'll get under the car tonight after my drive home and make sure I don't smell anything.

Do you really think a supercharged/tuned 2.5 can really beat a 3.2? Because I have been considering upgrading to an M, but the upgrade price is at least 14k currently (after taxes and such). I wonder how far you could get modding a 2.5 with that money; although you wouldn't get the other advantages of the M like the steering.

[SCHMOUPE]

Originally Posted by fighting_fish

I'll get under the car tonight after my drive home and make sure I don't smell anything.

Do you really think a supercharged/tuned 2.5 can really beat a 3.2? Because I have been considering upgrading to an M, but the upgrade price is at least 14k currently (after taxes and such). I wonder how far you could get modding a 2.5 with that money; although you wouldn't get the other advantages of the M like the steering.

unless you plan on driving a moded z4 to the ground, supercharging a 2.5 is a waste of money. As a rule of thumb (if you plan on selling one day) always buy the most expensive stock car you can afford. never buy something too simple and spend a fortune modding. You never get your fortune invested back.

[strokeZ]

To answer your question fighting - yes. You will have a consistent cubic buttload (techy term) of torque to play with. No you won't be the fastest thing out there, but it sure is fun. Shakib is right however BUT realize that there is little difference between the superchargers for the 2.5 and 3.0. I checked with the supercharger manufacturer and I can swap the thing to a newer 3.0 when the time comes for minimal investment. But yeah, I plan on driving it to the ground.

[pokeybritches]

You won't get a 2.5i to the point that it can all around smoke the M. If you want more than you have, get the M.

[Rick F.]

Originally Posted by fighting_fish

I was accelerating hard at high rpms from 3rd to 4th gear and experienced a sudden loss of power. I figured that the rpm limiter had kicked in, except right after I was hit with the smell of burnt breaks.

For the rest of the drive home the car felt different, as if the gear box had more play and the car had less power.

That section of my commute is a downhill where inexperienced drivers ride on their breaks, so it's not the first time I've smelt breaks in that spot. So what I felt could've been simply placebo effect (aka I thought there was something wrong, so it felt wrong). When I got home I popped the hood and didn't see or smell anything out of the ordinary.

Am I a victim of paranoia or could I have broken something?

Fish,

When you lost power, was the engine quiet or did you hear it suddenly racing much faster, followed by a staccato sound as the rev limiter kicked in?

If the former, there's any number of possible causes of temporary power loss, but most aren't very common. If the power loss occurred just as you shifted, is it possible that your left foot hit both the clutch and the brake pedal? That would cause the car to abruptly slow down (obviously).

If the latter, then it's possible that your clutch was slipping right after your shift to 4th. If the slipping occurred for more than just a moment, you might well pick up the smell of the clutch lining burning (which is a lot like overheated brakes smell). If you pull the handbrake on hard and try to drive off from a standstill in first, a good clutch will make the engine stall quickly. If the engine still runs, then the clutch is slipping badly and is on its last legs.

Remember: Problems that go away by themselves usually come back by themselves. Good luck tracking this down, and be sure to let us know what you find out.

Rick F.

[Endless619]

Originally Posted by Z4-Villalona

on another note a well tuned and supercharged 2.5 will rape a 3.2...ive done this.

It will not rape a tuned supercharged 3.2. I have seen this as well. The 2.5 will be left and I mean left. Over 500 bhp..peace...

And we dont want to start talking about HPF stage 1-4 turbo kits on the E46 M3 because they will put car lenghts on any boosted Z4 or Z4M..

Chris over at HPF was talking about maybe doing a Stage 2 kit for the Z4M... Over 700hp...

[fighting_fish]

I tried the hand brake test, and it stalled as expected. So I'm hoping it was just paranoia on my part.

While I have your attention, does anyone know what this is? I found it rattling around in the passenger door compartment

[fighting_fish]

Updates:

1. Was driving back down that hill and smelt burned breaks again. This time however I was driving with the girlfriend so I was cruising. She noticed the smell too, so on the way back we made it a point to drive through there again, and it's indeed that section of the road.

It's a long straightaway with a big downhill at the end, where the speed limit goes up to 50. I imagine people are just riding their breaks the whole way down.

2. That hook that I linked is part of the "storage" package. It's what holds the netting to the sides of the passenger foot well. Re-installed and all is good.

Thanks!

[dekaliber]

Glad to hear everything worked out.