Disappointed with Cold Start Delete on BM3

TWiTCHY

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Current OTS tunes from PTF does not completely eliminate cold start. My RPMs still idle high momentarily before decreasing to under 1000RPM. My goal is to eliminate the noise entirely. I purchased BM3 because I was under the impression that setting Cat Heating off would bring RPMs to 600RPM immediately as the feature is described to do when you set it to OFF, but it does not. Is a custom tuner able to make a BM3 map for me that will make start up go to 600RPM immediately, or is BM3 limited in its functionality to achieve this?
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Helicaldamn

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Ignorant question, but why do you want your car to drop RPM's so soon after startup?
 

7.insta

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Ignorant question, but why do you want your car to drop RPM's so soon after startup?
I guess probably to lower the engine startup noise , useful for early/late in the day when you don't wanna annoy your neighbors and such
 

Ordekalo

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Current OTS tunes from PTF does not completely eliminate cold start. My RPMs still idle high momentarily before decreasing to under 1000RPM. My goal is to eliminate the noise entirely. I purchased BM3 because I was under the impression that setting Cat Heating off would bring RPMs to 600RPM immediately as the feature is described to do when you set it to OFF, but it does not. Is a custom tuner able to make a BM3 map for me that will make start up go to 600RPM immediately, or is BM3 limited in its functionality to achieve this?
You need to warm up the engine before driving you car.
If you eliminate the cold start, this can cause damage your engine because it will allow the engine to run the oil although the oil is still cold.

My advice, think twice before this mod. Your neighbors will not buy you a new engine.
 

Twisted Tuning

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You need to warm up the engine before driving you car.
If you eliminate the cold start, this can cause damage your engine because it will allow the engine to run the oil although the oil is still cold.

My advice, think twice before this mod. Your neighbors will not buy you a new engine.
the CAT heating cycle which is mainly what cold start is. Is meant to heat the cats up as fast as possible for emissions. This cycle generally only lasts about 60 seconds while the O2s go through their checks. That's the main reason for the raised engine speed at cold start. To feed as much exhaust gas to the CAT as possible to heat it up. Engine wear is also why the cold start typically will not raise the RPM more than like 2000rpm or so. Because high revs hurt cold engines.

You aren't hurting anything if you are catless and disable cold start. There is no use for it other than noise when you're catless.
 

Ordekalo

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the CAT heating cycle which is mainly what cold start is. Is meant to heat the cats up as fast as possible for emissions. This cycle generally only lasts about 60 seconds while the O2s go through their checks. That's the main reason for the raised engine speed at cold start. To feed as much exhaust gas to the CAT as possible to heat it up. Engine wear is also why the cold start typically will not raise the RPM more than like 2000rpm or so. Because high revs hurt cold engines.

You aren't hurting anything if you are catless and disable cold start. There is no use for it other than noise when you're catless.
Cold starts are more difficult than starting a vehicle that has been run recently (typically between 90 minutes and 2 hours). More effort is needed to turn over a cold engine for multiple reasons:

The cat temp is less than important for this one.

Once you Rev an engine which is cold, the oil high viscosity due to low Temps can cause the oil not to be fully filled to every stroke of the engine. And that will lead to engine damage and warn bearings.

Please do not recommend anyone to "disable cold start".

It is good also that the turbo will get feeded with warm oil before putting to work.
 

Twisted Tuning

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Cold starts are more difficult than starting a vehicle that has been run recently (typically between 90 minutes and 2 hours). More effort is needed to turn over a cold engine for multiple reasons:

The cat temp is less than important for this one.

Once you Rev an engine which is cold, the oil high viscosity due to low Temps can cause the oil not to be fully filled to every stroke of the engine. And that will lead to engine damage and warn bearings.

Please do not recommend anyone to "disable cold start".

It is good also that the turbo will get feeded with warm oil before putting to work.

Either you didn't read what i wrote, or you didn't understand fully what i wrote.

Cold Start (Specific to this Engine/Car)

1. 99% of its purpose is for Cat Heating and emissions.
2. At start, with Cold start enabled, the RPM is high and gradually decreases over about a span of 60 seconds or so
3. Disabling cold start removes the high rpm of the engine at start.
4. the high starting rpm is to send as much exhaust gases to the cat as possible to heat it, so the cat starts doing its jobs.
5. Cold start also increases fuel injection and retards timing to make more heat for the cat.

We all know cold start is harder than a warm start. The part of what you just said about revving a cold engine is why the non high RPM start of disabled cold start is not an issue. I'm not exactly sure what you were trying to say. But everything i have said is 100% specific to this Engine and Car.
 

Axix23

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Its funny, bc my problems with turbo cars with bigger injectors has always been hot starts... Its usually when my ect is still hot and the car has only been sitting 15-30 min after the car was driven for 1-2 hours... I always had to change the parameter setting in relation to cranking fuel % vs ect and also iat..
 
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TWiTCHY

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Highly doubt the 10 seconds of cold start that BM3 reduced from 60 seconds is doing anything worthwhile except for being excessively loud in the neighborhood and parking lots. I just want it to start quietly
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