ESS Tune on a Leased Z4 35i?

[blschaefer1]

How risky is this really?

I would prefer to go the Dinan route for the warranty they provide but they don't have their tune released for my model year (2012) of the 35i, only 35is.

Seeking opinions on issues with BMW warranty before I pull the trigger.

Thanks.

[nicknaz]

My take is that when people break their chip tuned motor there is something else at play, such as "money shifting" or oil starvation from tracking the car with r compounds (e.g. high g long sweeper)

You are in CA right? Datalog to make sure your tune is not causing detonation with CA 91 octane (supposedly worse than other 91 octanes... COBB has a low power CA 91 octane tune, for example). You might need to mix 100 octane.

[blschaefer1]

I assume its impossible to "money shift" a DCT equipped car?

[nicknaz]

Originally Posted by blschaefer1

I assume its impossible to "money shift" a DCT equipped car?

Correct. Computer will ignore the request.

Random thought... COBB has a 30 day return policy.. try before you buy ?

[blschaefer1]

As I understand it:

I believe Cobb requires breaking into the ECU to install, which might make it easier to detect if it needed to be uninstalled for any BMW warranty work, as opposed to ESS which is software only installed via the OBD port and the OEM flash can be easily reinstalled before taking it to the dealer.

Am I correct on this?

[army_men]

im running cobb on a manual and its a ecu software flash through the obd port. nothing physical installed on the car. no issue on warrantee so far. my 2 cents.

[markmatthews]

also interested in finding out if dealers can trace a tune even after it's removed on a Z4?

[HABANEROTE]

They can only WRITE to ECU they don't have software available to READ, so yes they can overwrite your tuning, but they can also do a test drive and be like WTF?

My Service Advisor came running to me asking me what the hell was installed in my car... l said nothing...

[nicknaz]

No one has shared specifics with me on how but I've been told twice that engineers from the factory can find "footprints" that the car was chip tuned (and are called in to do just that in the case of big ticket warranty claim).

[blschaefer1]

Originally Posted by nicknaz

No one has shared specifics with me on how but I've been told twice that engineers from the factory can find "footprints" that the car was chip tuned (and are called in to do just that in the case of big ticket warranty claim).

This is what is making me nervous.

[nicknaz]

Easy answer is keep it stock

Check out the E90 boards. I haven't seen any 335is (N54 + DCT) threads about drivetrain failure other than some DCT clutch slip when repeated drag racing a full bolt on car, and I haven't seen any N54 threads about engine failure with just a chip

[blschaefer1]

Originally Posted by nicknaz

Easy answer is keep it stock

Check out the E90 boards. I haven't seen any 335is (N54 + DCT) threads about drivetrain failure other than some DCT clutch slip when repeated drag racing a full bolt on car, and I haven't seen any N54 threads about engine failure with just a chip

I'm sure it is fairly safe. I have not heard any horror stories either. Somehow $900 for a huge increase in HP and torque is very irresistible! Cobb or ESS seems like the way to go.

[Vintage]

any good SA will know your car is tuned via "footprints" because the turbos "overspec" from the factory settings - so, trust me, they do not see the software itself but they do see the results if they so desire

[nicknaz]

Cobb claims to back up the PCM and uninstall means writing back the exact values that were there prior to install.

@vintage does the "over spec" live in a part of the PCM the Cobb can't write to?

[Vintage]

nicknaz - good question; I imagine the best person to ask is Trey Cobb because I have no clue. when I get back in town I will try to ask him (we live in the same neighborhood - strange but true and he is super nice).

[nicknaz]

Originally Posted by Vintage

nicknaz - good question; I imagine the best person to ask is Trey Cobb because I have no clue. when I get back in town I will try to ask him (we live in the same neighborhood - strange but true and he is super nice).

please let us know. tech from a good source like that is always welcome.

[VailM3]

Have Cobb on my 35iS Agressive Stage 1 LT. Being able to ease on the power is great and the addition power plus always on overbost, can chirp in 3rd gear on my set of PSS.

[Kessler35is]

Originally Posted by VailM3

Have Cobb on my 35iS Agressive Stage 1 LT. Being able to ease on the power is great and the addition power plus always on overbost, can chirp in 3rd gear on my set of PSS.

I am getting that type of tire noise from my ESS tune also. It sounds like both tunes really awakens this engine from its factory sleep.

[blschaefer1]

Originally Posted by nicknaz

Cobb claims to back up the PCM and uninstall means writing back the exact values that were there prior to install.

@vintage does the "over spec" live in a part of the PCM the Cobb can't write to?

So yesterday I stopped by Cobb's SoCal facility (nice, clean shop with great staff), and had a conversation with one of their techs. He indicated that their AccessPort first copies the OEM flash from the ECU to the device, then overwrites the ECU with the selected Cobb flash. Once this is done, all history data from the ECU (sensors, etc.) is reset.

As such, if the OEM flash it re-written (or the Cobb flash un-installed, as they call it), there will be no history data either (or very limited data, depending on how long before the visit to the dealer the OEM flash was re-installed). A service tech might find this unusual, but it can be easily explained that the vehicle's battery ran down on an extended vacation or something, hence the reason for limited history data. That is if it was ever questioned, which is doubtful.

Cobb currently has the V2 version of their AccessPort on sale for $795 as there is a V3 version with larger screen pending release. I decided to give it try, as they have a 30 day money back guarantee.

I am VERY impressed with both the ease of use and results. Upon connecting the unit to the OBD port, it first backs up the OEM flash which takes about 10 minutes. There are many map options on the unit. Cobb was nice enough to download the latest maps while I was there, so when I got home I did not need to go through the exercise of updating via Cobb's server.

It was suggested that I use the least aggressive map (Stage 1 Drive) as a starting point due to the crappy fuel we have in CA, AZ, and NV. It took about 8 minutes to load the new map into the ECU. The only thing I found unusual is that the fuel pump seemed to run most of the time during the install.

I first went with the Linear Throttle version of this map, and took the car for a spin. The increase power was clearly there, but it felt a bit like driving a naturally aspirated motor as the intent is to make the power curve more even. Kind of strange, but I could have gotten used to it.

I then installed the Stock Throttle version if this map (with only took about a minute), and wow, what a difference. Instant torque right off the line, and when cruising at highway speeds the increase increase in power is dramatic. This from their most conservative map!

Anyway, sorry for the verbose write up, but I am so far really impressed with the Cobb product and also in my dealings with the company.

[VailM3]

Oh and OP you might want to consider COBB over ESS since you leasing as you can sell the COBB after the lease is up. By now both products are equally as good reading the reviews and comments by users.

The only advantage is that you aren't vin locked with COBB as you are with ESS. Cant go wrong with either though regarding performance.

[blschaefer1]

Originally Posted by VailM3

Oh and OP you might want to consider COBB over ESS since you leasing as you can sell the COBB after the lease is up. By now both products are equally as good reading the reviews and comments by users.

The only advantage is that you aren't vin locked with COBB as you are with ESS. Cant go wrong with either though regarding performance.

Yep, thanks. I am the OP and I posted above concerning my visit to Cobb SoCal and resulting purchase. Great product.

[VailM3]

Originally Posted by blschaefer1

Yep, thanks. I am the OP and I posted above concerning my visit to Cobb SoCal and resulting purchase. Great product.

So you are at ST Stage 2 Aggressive or Sport?


I am running LT Stage 1 Aggressive on mz 35is (essentially as stage 2 for 35i) I agree its LT make the power come on tap feel like a NA engine. Not a bad thing just not used to it.