Throwing a code P1728

E90gone · 02-19-2014, 10:10 AM

Went to the track with my 335i 08 auto. Mods DP, intercooler, exhaust, charge pipe, intake, jb4 tune 2. Car slipped going into 3rd. Service engine soon comes on I take it easy to the end. Pull the code p1728, my understanding is it's a Transmission slip code. Shut the car off, wait about an hour for my next run the code stays off the rest of the day. I drive home on tune 0 stays off. Yesterday, I am driving to work on tune 0 and the light comes back on same code p1728
Not even driving the car hard or anything. I cleared the code it stays off till I drive home later in the day, same thing this morning. P1728, the car doesn't feel any different, but I might be a fraction of a second longer going into third. What is the problem with the car? And what is that code normally?

TheBingoBalls · 02-19-2014, 10:20 AM

I believe that code is for the transmission slipping.

E90gone · 02-19-2014, 10:22 AM

I know it's for the tranny slipping but what does that mean?

135Pats · 02-19-2014, 10:28 AM

Quote:

Originally Posted by E90gone

I know it's for the tranny slipping but what does that mean?

It means you’ve started to/already have burn up the disks. Not good. What type of WTQ are you making? Do you launch the car frequently? Have you ever serviced the 6AT, do you have Alpina flash? Lot’s to look into here.

AlpineSwift · 02-19-2014, 10:30 AM

Could be worn seals, could need a fluid change, worn trans bands, a clogged trans filter, faulty torque converter, etc. Could literally be any number of different things.

E90gone · 02-19-2014, 10:36 AM

I have no idea how much wtq I am making. Car has 49k on it, fluids never been changed. I have had the tune for maybe 2k and mostly drive in 0 maybe only 500 miles in 2 and only drove the car hard at the track this past weekend. No alpha tune.

E90gone · 02-19-2014, 10:38 AM

I would say 99% of the time I am rarely in boost when I drive the car, I drive it like an old lady. I have lunched the car hard maybe 10times total 5-7 of which was on tune 0. 3 on tune 2.

E90gone · 02-19-2014, 05:14 PM

Anyone else have any ideas?

kfriceman · 02-19-2014, 05:21 PM

Quote:

Originally Posted by E90gone

I would say 99% of the time I am rarely in boost when I drive the car, I drive it like an old lady. I have lunched the car hard maybe 10times total 5-7 of which was on tune 0. 3 on tune 2.

When ever you drive you are always making boost, the amount may vary but it never stops.

-Kevin

El Cheapo Loco · 02-19-2014, 05:27 PM

With that code, your handle sounds prophetic now.

E90gone · 02-19-2014, 09:56 PM

Started changing the fluid today hopefully that fixs it.

02-19-2014, 10:10 AM	#1
E90gone First Lieutenant 20 Rep 352 Posts Drives: E90 Join Date: Jun 2013 Location: Tampa, FL iTrader: (4)	Throwing a code P1728 Went to the track with my 335i 08 auto. Mods DP, intercooler, exhaust, charge pipe, intake, jb4 tune 2. Car slipped going into 3rd. Service engine soon comes on I take it easy to the end. Pull the code p1728, my understanding is it's a Transmission slip code. Shut the car off, wait about an hour for my next run the code stays off the rest of the day. I drive home on tune 0 stays off. Yesterday, I am driving to work on tune 0 and the light comes back on same code p1728 Not even driving the car hard or anything. I cleared the code it stays off till I drive home later in the day, same thing this morning. P1728, the car doesn't feel any different, but I might be a fraction of a second longer going into third. What is the problem with the car? And what is that code normally?
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02-19-2014, 10:20 AM	#2
TheBingoBalls Brigadier General 3821 Rep 4,660 Posts Drives: BMW Join Date: Mar 2011 Location: Toronto, Ontario iTrader: (1) Garage List 2018 F36 BMW 440i x ... [0.00]	I believe that code is for the transmission slipping.
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02-19-2014, 10:22 AM	#3
E90gone First Lieutenant 20 Rep 352 Posts Drives: E90 Join Date: Jun 2013 Location: Tampa, FL iTrader: (4)	I know it's for the tranny slipping but what does that mean?
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02-19-2014, 10:30 AM	#5
AlpineSwift Colonel 77 Rep 2,114 Posts Drives: 2008 335Xi Coupé Join Date: Feb 2010 Location: Castle Rock, CO iTrader: (3)	Could be worn seals, could need a fluid change, worn trans bands, a clogged trans filter, faulty torque converter, etc. Could literally be any number of different things. __________________ E92 '08 335Xi 6AT - Cobb AP3 Tuned by MAC Autosport, Original Prototype Xi DOCRace 6266 Single Turbo Swap, VRSF CP w/Synapse BOV, VRSF 7" FMIC, BMS Cowl, H&R Coilovers, Renn Motorsport RS-51's, Stoptech Stage 2 Slotted, xHP Stage 3, Earl's Racing Oil Cooler, Turner Boost Gauge, M3 Lip Spoiler. Standing Mile Record Holder for Xi over a mile high: 168.2MPH @ 5512'; The Colorado Mile hosted by The US Mile.
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02-19-2014, 10:36 AM	#6
E90gone First Lieutenant 20 Rep 352 Posts Drives: E90 Join Date: Jun 2013 Location: Tampa, FL iTrader: (4)	I have no idea how much wtq I am making. Car has 49k on it, fluids never been changed. I have had the tune for maybe 2k and mostly drive in 0 maybe only 500 miles in 2 and only drove the car hard at the track this past weekend. No alpha tune.
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02-19-2014, 10:38 AM	#7
E90gone First Lieutenant 20 Rep 352 Posts Drives: E90 Join Date: Jun 2013 Location: Tampa, FL iTrader: (4)	I would say 99% of the time I am rarely in boost when I drive the car, I drive it like an old lady. I have lunched the car hard maybe 10times total 5-7 of which was on tune 0. 3 on tune 2.
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02-19-2014, 05:14 PM	#8
E90gone First Lieutenant 20 Rep 352 Posts Drives: E90 Join Date: Jun 2013 Location: Tampa, FL iTrader: (4)	Anyone else have any ideas?
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02-19-2014, 05:27 PM	#10
El Cheapo Loco douchebaggo 186 Rep 972 Posts Drives: stick Join Date: Oct 2009 Location: CA iTrader: (1)	With that code, your handle sounds prophetic now.
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02-19-2014, 09:56 PM	#11
E90gone First Lieutenant 20 Rep 352 Posts Drives: E90 Join Date: Jun 2013 Location: Tampa, FL iTrader: (4)	Started changing the fluid today hopefully that fixs it.
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