Cold weather cold start in the morning.. Hesitation on D mode

[lhordmclain]

2004 e53 m54 3.0

Already scanned / run diagnostics

* no stored codes that will hint transmission slipping
* battery charge test was OK

Symptom: switching the gears to D the truck won't move, I need to rev up a couple of times before it moves forward. After that it feels fine, no check engine light or battery light.

Frequency: SUV sitting overnight ( 1st start every morning and on cold temp 20F and below )

[upallnight]

If you are using a generic OBD II scanner it will NOT scan any EGS codes.

Could be a little low on ATF because of the cold weather ATF contracts and if it it was just marginal it could be the source of your problem. Once warm ATF will expand.

[Brandon002]

How many miles are on it?

Have you ever had the transmission serviced? If it's not going in to D or R when cold, or hesitates until it's warmed up I would seriously check the fluid level and if you're over 100K miles and have never had the transmission serviced (pan drop, filter replacement, torque converter flush) now would be the time to do it.

[LeiZ]

I tend to agree on the low ATF level.

GL

Originally Posted by upallnight

If you are using a generic OBD II scanner it will NOT scan any EGS codes.

Could be a little low on ATF because of the cold weather ATF contracts and if it it was just marginal it could be the source of your problem. Once warm ATF will expand.

[lhordmclain]

78k miles only

* We used BMW GT1 running diagnostics
* last Summer , we serviced the transmission ( AT filter+gasket kit and drained+refilled using redline ATF) and serviced the transfer case drained + refilled with BMW TC Fluid (+reset the VTG - oil wear)


Updated Software (ISTA/P Reprogramming EGS) - 30mins

Control Unit: EGS
Part # Prog ECU (Old): 7542040
Part # Prog ECU (New): 7557980

[lhordmclain]

My concerns has been put to sleep!


Reason #1 Federal Register, Volume 69 Issue 91 (Tuesday, May 11, 2004)

Reason #2 (see below)

it is "normal" - in fact it is by design so as to warm up the engine/transmission as soon as possible for optimum efficiency and also to lessen pollution by activating the cats.


It is actually a good thing for the whole car as well - you want the engine to get up to operating temperature as quickly as possible (cleaner combustion so less harm) and warmer for defrost, etc.



Engine Warm Up Cycle: Based on the monitored transmission oil temperature (system specific), or engine coolant temperature (CAN), the TCM raises the shift points to that of the
Sport program when driving just after initial cold start. This is implemented to raise the engine RPM which speeds up the warm up cycle of the catalytic converter.

This function is terminated if:
• The vehicle exceeds 37 MPH,
• Transmission oil or engine coolant temperature exceeds 60 C.
• A maximum of three minutes is exceeded.

Here are 3 documents that will give you some
info on your tranny as well as a few others. the engine temp does figure into the tranny shift program along with a variety of other variables.
You might want to save and print these, lots of good info.

http://home.comcast.net/~jimlev/electran2.pdf

http://home.comcast.net/~jimlev/transfund1.pdf

http://home.comcast.net/~jimlev/BMW_Tranny_Specs.pdf

==========================
Diagnosis and Troubleshooting
============================

Due to the cost and complexity of today's electronic transmissions, BMW recommends that the technical hotline be contacted before any repairs are performed. It is important that the technician perform some basic diagnostic procedures before contacting technical assistance. The following procedures should be followed:

• Always Verify customer complaint, make sure the complaint is not related to normal operation. (i.e. "Warm Up Phase", AGS operation etc.)

• Survey Fault Memory - Perform complete quick test. There may be other systems that interface with EGS that could cause faults. (i.e DME, ASC/DSC, IKE/Kombi etc.)

• Print out all fault code with fault conditions. Also print out copy of Identification page and diagnostic report.

• CHECK TO SEE IF THERE ARE ANY SERVICE BULLETINS THAT APPLY TO YOUR SPECIFIC COMPLAINT. THIS INCLUDES THE SERVICE ROUNDTABLE.

• Ensure that battery voltage is sufficient. Battery voltage must be greater than 12.5 with ignition switched off. Check battery connections for tightness and condition.

• Check ground connections. (chassis to engine, grounds to bulkhead and shock tower.)

• Check over vehicle to look for transmission leaks, physical damage, loose connections etc.

• If necessary, check fluid level and condition using DISplus or GT-1.

• Check to see if any aftermarket or performance components have been installed that could effect transmission operation. (DME or EGS software as well as any engine modifications).

• Check repair history to see if there were any recent repairs that could effect the proper operation of the transmission (i.e. Engine replacement with damaged dowel pin etc.).

• Check DCS for any open campaigns or recalls pertaining to drivetrain.

• Check and record chassis number, production date and transmission serial # before contacting technical assistance.

[garrett.fell]

Outstanding information. Thank you.


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[bcredliner]

Great post!