I have an 03 MCs with 126k. Almost immediately after punching the gas during some spirited driving, I get a weird smell in the cabin. Smells like a combo of things, coolant, oil, musty water, moldy bathroom, are some examples. They're haven't been any puddles on the garage floor, but I concerned it may be a sign of something bad.
If I'm just driving around I don't smell anything, only on spirited high rpm runs.
Any suggestions on where to look?

 

check if the drain for the ac/heater box is open.
check the coolant level.

 

I get the same thing in my 04 JCW. I think it has to do with the super charger heating up really quick. I will pay attention to the smell to see how I would describe it next time I drive the car. First time I smelled it I was worried but then I realized it only occurred when I pushed the car.

 

The coolant smell is rather normal, my car does the same thing when I get spirited. If you're smelling a rotten egg smell or something of the sort that is the catalyst burning off the built up "contaminates" it has collected. As for a moldy bathroom smell it could be a clogged AC drain, but it doesn't correlate to the fact of only getting the smell under hard acceleration.

 

Could it be the header gasket, like an exhaust leak?

I'll check the ac drain plug also, I don't know where its at though

 

BTW, coolant and oil lvl haven't changed at all

 

Have you looked under the hood to see of anything is dripping on the exhaust? If the expansion tank is leaking, it will have a dried whitish crust on it, usually around the seam...easy fix.
Hopefully you HAVE checked your fluid levels....these cars tend to leak a little....sometimes in insidious ways, NOT leaving a drip on the floor...the thermostat housing for one can leak pretty bad, and NEVER leave a visible drop on the floor. Same for the expansion tank on the S.

 

No crust on the coolant rez but the power steering one was low and it looks like it has been leaking down the hose closest to the engine. I tried to find the leak but I think the level is to low. I'm not sure at the moment if its the rez or hose. Clamps seem tight though...

I did have the power steering pump replaced last summer under the recall thing, I guess they just replaced the pump and not the hoses or rez...

And if that was getting sprayed on a hot header, that would stink huh.

 

I had a similar issue, but I've just replaced the header and cat and the smell has gone.

 

Any good reviews on obx headers?

http://www.cntracing.com/mobile/prod...FWxp7AodzwIAXg

 

It's possible the clutch is starting to slip. And the burnt smell is the clutch material. Does it only do it under hard accelleration? If the clutch pedal is engaging high on the pedal, its possible that the clutch pressure plate is loosing clamping force.

Most exhaust leaks are pretty easy to find since you can typically hear the exhaust noise. Oil leaking on exhaust does have a distinct smell, and typically has some evidence of stains on the exhaust, and smoke.

 

could very well be the clutch...since i've watched way to many Mod Mini youtube videos i seem to get a bit paranoid about alot of things with this mini. i'm afraid also that i have a main seal leak also....off to watch some more Mod mini!

further down the rabbit hole.

there is a leak from the pressure hose on the power steering rez... so far.

 

I had the strange smell thing happen to me on a track day, turned out to be the ride along had soiled himself....

Motor on!

 

If the clutch is slipping the engine will typically accellerate a little faster that the car. Other symptoms are the clutch pedal engages almost at the very top of the travel.

 

that had to stink for sure, but the smell i smell is not feces...

could it be a loose belt? as i get on it it slips? maybe a worn out belt tensioner? i watched it today and you can see it moving, should it not be that obvious?

 

how do you tell if the belt tensioner is bad, I don't see any holes behind the spring and the twisted metal tab is still there. I already ordered and received the new tensioner and belt, but now I'm thinking I'm getting too OCD from reading soo many posts about alota stuff.

 

Changed the belt tensioner and I found some new issues. If you refer to the pictures, it looks like one of the motor mounts is shot.

I'm guessing I have a 15% pulley, but does anyone know who makes the one you see in the picture?

Lastly, is there a seal under the crank pulley? If so, I think its leaking.

Any input would be appreciate d.

 

If the smell is eggy, it's a fuel, exhaust related issue. When you punch it all the sensors tell the injectors to run rich. Like someone said earlier new header and cat, or maybe O2 sensors are on their way out.

 

Forgot to add pictures....

I'll look more at the header once I get the subframe out, thanks for the suggestion

 

Let me know what you find cause I'm having a similar issue.

 

Give you motor a good cleaning...
When you get it good and hot...and oil, etc that has leaked onto it will start to bake...giving off smells..
Just like a new motor smells funny the first time you get on it as paint and other coatings are burnt off....
If you have leaks...fix em, or monitor them...and check for exaust leaks...but that smell is different...
Doing stuff diy is good, but if you don't know what too look for...get a pro...I do sometimes, $$ well spent.
If you wipe the dirt off the end of your pulley...it SHOULD have a # stamped on it for a reduction...most brands do anyway.

 

That's a Helix pulley. I don't even need to see the picture to tell you that, at your mileage, your motor mount is shot (unless you replaced it within the last 20-30k). That moisture under your crank pulley may indicate a front seal leaking, but it's more likely that it's your oil pan gasket. Get a flashlight and look for moisture under the crank pulley. As you've now discovered, things that leak on all R53s include but are not limited to: oil pan gasket, crank sensor seal, all three power steering lines. It's part of the price of ownership.

 

Thanks to you both, I monitor every drip and smell , and search and read all posts related, but I was getting ocd about it all until I was vilified by what I found in the pics. Now I need to remove the crank pulley to get to the front seal right? Good time to replace it, huh.(if its not the oil pan gasket). Do you have too cook all crank pulleies to get them on?

I've got a pretty sizable wish list on amazon, from ball joints to the radiator housing...

I've truly have a love/hate with this car, but it'll be cheaper to get this car right than have a new car payment. I love the car, its my wallet that doesn't. And yes, its the DIY that's allowed me to keep this car, but if I'm not comfortable/feel safe about a job, its going to a pro.

 

i'll be dropping the subframe to change the inner/outer ball joints, control arm bushings and power steering hoses, as well as replacing the upper motor mount. hopefully I'll have a clearer view of the engine to determine if the oil pan gasket is leaking or anything else that needs to be done.


I've watched a few videos on youtube and some write-ups here, but is the any pointers out there?

 

What about the heat exchanger? Or oil cooler? It could be the seals behind it huh...