Cold Start issue (normal?)

rmanm4 · 05-18-2021, 03:16 PM

Quote:

Originally Posted by FriedPiston

The N55 have both O2 sensors in the same catlytic converter. This is still a normal cold start condition for the S55, even with with the cold start sequence disabled. Feel free to chase this down as a phantom issue, it surely won't hurt anything.

N55 has one pre-cat and one post-cat O2, that's only because its a single turbo system.

I still feel this is a waste gate characteristic on the model of turbos used on the S55. Either way seems totally normal and nothing to worry about!

NYG · 05-18-2021, 03:17 PM

Quote:

Originally Posted by rmanm4

Totally understand that, but why doesn't it show up on the N55? I've had many years of experience with M54, S54, N52, N55 and now S55 and only have seen this on the S55. Is the timing on cold start that much advanced to run RICH? Also running rich is cooler then running lean, lean would have higher exhaust temps for heating up cats.

http://s3.bimmerfile.com.s3.amazonaw...S55-Engine.pdf

Short Answer: Emissions + Power/TT + 2nd High Pressure Fuel Rail

The S55 probably runs richer than the N55 too but this is just a reasonable guess.

Your exhaust pipe gets more and more regulated every single year.

FriedPiston · 05-18-2021, 03:24 PM

Quote:

Originally Posted by rmanm4

N55 has one pre-cat and one post-cat O2, that's only because its a single turbo system.

I still feel this is a waste gate characteristic on the model of turbos used on the S55. Either way seems totally normal and nothing to worry about!

Wastegates remain shut during idle, just take a live look at your monitors. This cold start condition happens with stock turbos, PS2s, GC+, etc.

rmanm4 · 05-18-2021, 04:45 PM

Quote:

Originally Posted by FriedPiston

Wastegates remain shut during idle, just take a live look at your monitors. This cold start condition happens with stock turbos, PS2s, GC+, etc.

Yes, during idle they are shut, but during cold start they are open. Idle is not in question here, it's what is happening during cold start.

Adcampo · 05-18-2021, 06:41 PM

Can't comment on your concern. But jeez it's amazing how much the S55 sounds like a lawn mower. Please don't be offended, that's coming from an owner.

NYG · 05-19-2021, 09:26 AM

Quote:

Originally Posted by Adcampo

Can't comment on your concern. But jeez it's amazing how much the S55 sounds like a lawn mower. Please don't be offended, that's coming from an owner.

I don't think anyone without hearing loss would disagree.

rmanm4 · 05-19-2021, 09:33 AM

Quote:

Originally Posted by Adcampo

Can't comment on your concern. But jeez it's amazing how much the S55 sounds like a lawn mower. Please don't be offended, that's coming from an owner.

Funny story:

When I was playing the video for the SA at the dealership, the other SA and the secretary thought I was showing my new Lawn Mower for some reason! It was a gut punch that the SA also said I cannot upgrade down pipe or mid pipe as I would effect my warranty. His explanation for it was that it would alter the exhaust pressure and could effect engine performance.

NYG · 05-19-2021, 09:41 AM

Quote:

Originally Posted by rmanm4

Funny story:

When I was playing the video for the SA at the dealership, the other SA and the secretary thought I was showing my new Lawn Mower for some reason! It was a gut punch that the SA also said I cannot upgrade down pipe or mid pipe as I would effect my warranty. His explanation for it was that it would alter the exhaust pressure and could effect engine performance.

Be glad you didn't. It just makes it a louder lawn mower.

There's just no way to make it sound good - just more obnoxious.

rmanm4 · 05-19-2021, 10:13 AM

Quote:

Originally Posted by NYG

Be glad you didn't. It just makes it a louder lawn mower.

There's just no way to make it sound good - just more obnoxious.

I agree....I have yet to hear a exhaust setup that sounds really good. You cant make a I6 sounds like a V8 or even a V6.

I now close the flap and let my intake sounds take over and enjoy that a lot more!

NYG · 05-19-2021, 10:38 AM

Quote:

Originally Posted by rmanm4

I agree....I have yet to hear a exhaust setup that sounds really good. You cant make a I6 sounds like a V8 or even a V6.

I now close the flap and let my intake sounds take over and enjoy that a lot more!

It has a unique personality to it which I appreciate. Even though V8s sound good, there's some V8 cars that the manufacturer specifically targets the same overused/boring sound with every model. I think the factory level of sound BMW sets is perfect. It's not a pretty sound but it's got character.

E92s sounded so damn good after the E46.

rmanm4 · 05-19-2021, 10:56 AM

Quote:

Originally Posted by NYG

It has a unique personality to it which I appreciate. Even though V8s sound good, there's some V8 cars that the manufacturer specifically targets the same overused/boring sound with every model. I think the factory level of sound BMW sets is perfect. It's not a pretty sound but it's got character.

E92s sounded so damn good after the E46.

E92 does sound really good, so does the E39 M5.

I went from e46 M3 to F82 M4 and skipped the E92 M3 on purpose. I just didnt feel enough enjoyment out of the E92. It lost a lot of soul over the 46 and didnt really make up for it in looks, interior or torque! The G82 I waited on and loved the interior and power, but I just couldnt stomach that front grill and even its lines. So, I found a new F82 that hit the spot. SMG to DCT is night and day and the power the S55 makes is night and day over the S54.

irunalot · 05-19-2021, 11:32 AM

Mine does the exact same thing on cold start, sounds like is missing. Runs fine after it warms up.

NYG · 05-19-2021, 12:13 PM

Quote:

Originally Posted by rmanm4

E92 does sound really good, so does the E39 M5.

I went from e46 M3 to F82 M4 and skipped the E92 M3 on propose. I just didnt feel enough enjoyment out of the E92. It lost a lot of soul over the 46 and didnt really make up for it in looks, interior or torque! The G82 I waited on and loved the interior and power, but I just couldnt stomach that front grill and even its lines. So, I found a new F82 that hit the spot. SMG to DCT is night and day and the power the S55 makes is night and day over the S54.

I mean, in terms of performance the F8X is leaps and bounds ahead of previous gens. If only they packaged it with a sportier suspension and front brakes.

rmanm4 · 05-19-2021, 12:39 PM

Quote:

Originally Posted by NYG

I mean, in terms of performance the F8X is leaps and bounds ahead of previous gens. If only they packaged it with a sportier suspension and front brakes.

Suspension in the F8x is designed to be more luxury drive over previous gens. e46 suspension was extremely harsh and connected compare to e92 or f82. The F82 suspension needs work to get more firm and connected where you can take a turn with full confidence! I could predict my e46 at every turn and even drift the turn!

With the F82 I feel like im blind. I dont have that connection. I just cant predict it. I may need more kms on it to understand its limits more. I do have lowering springs to install to see if I can find a sweet spot without doing B16 upgrade.

As for breaks...I had ZCP upgraded breaks on my e46 M3 and they are about the same as the F82.

c0nrad · 12-18-2021, 10:23 AM

this started happening to me after dealer replaced my spark plugs fwiw. haven't brought it back in yet but will soon

mzvertigo · 03-16-2023, 06:46 PM

Curious, but did you ever get any misfires after this OP?

05-18-2021, 06:41 PM	#27
Adcampo Lieutenant Colonel 882 Rep 1,661 Posts Drives: G80 Manual Join Date: Apr 2013 Location: Ashburn Va iTrader: (1)	Can't comment on your concern. But jeez it's amazing how much the S55 sounds like a lawn mower. Please don't be offended, that's coming from an owner. __________________ 18' F80 6MT, 991.1s cab PDK, F83 6mt, 996 C4S cab 6mt, F30 328iM 6mt E60 M5 SMG, E39 M5, E46 M3 cab 6mt, E36 M3 5mt
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05-19-2021, 11:32 AM	#34
irunalot Captain 1518 Rep 820 Posts Drives: Porsche Carrera S Join Date: Oct 2020 Location: Miami iTrader: (0)	Mine does the exact same thing on cold start, sounds like is missing. Runs fine after it warms up.
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12-18-2021, 10:23 AM	#37
c0nrad Second Lieutenant 93 Rep 243 Posts Drives: 2018 F80 M3 ZCP Join Date: Jun 2016 Location: NJ iTrader: (1) Garage List 2018 M3 [0.00]	this started happening to me after dealer replaced my spark plugs fwiw. haven't brought it back in yet but will soon
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03-16-2023, 06:46 PM	#38
mzvertigo New Member 0 Rep 12 Posts Drives: 2020 BMW M2 Competition Join Date: Oct 2019 Location: San Francisco Bay Area iTrader: (0) Garage List 2020 BMW M2 Competi ... [0.00]	Curious, but did you ever get any misfires after this OP?
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