engine learning

[muzz]

Hi
I do not use my 944s very often, after driving it I parking it up in the garage and disconnect my battery. It may be a week or more before I use it again.
My question is does the engine management system have to learn all the idle and running etc for it to be back to normal.
Any proof that this disconnecting of the battery can cause running problems will be appreciated.

many thanks

 

[TTM]

Disconnecting the battery won't have any ill effect whatsoever.

 

[Veerzigzag]

Disconnecting the battery won't have any ill effect whatsoever.

...apart from not being able to open the boot to connect the battery again...

 

[Chrishazle]

If you have power available in the garage, why not connect up a battery conditioner instead of disconnecting the battery? It's what I've done for the past 15 years with both the 968's - a coupe and now the cabriolet. The wires are so thin you can still close the rear hatch (or boot lid on the cab) over the wires, it not only keeps the battery fully charged for next time you use the car, it also (IMHO) enhances battery life. I had to replace the battery on the coupe not long after buying it - so probably 5 years old. I had the car 12 1/2 years and never again replaced the battery!

Ctek do good conditioners, or keep an eye on Lidl special offers, they occasionally do one for about £20 that, from reports I've read, is just as good but less than half the price of a Ctek.

 

[Veerzigzag]

^^^^^^^^^^
+1 for C-Tek: excellent devices.

 

[jasonp]

ORIGINAL: Veerzigzag

^^^^^^^^^^
+1 for C-Tek: excellent devices.

another +1 for c-tek,,great bit of kit,,,,jasonp

 

[bmnelsc]

ORIGINAL: TTM

Disconnecting the battery won't have any ill effect whatsoever.

+1 here. I used to disconnect my battery over winter (and of course, when working on various things) and no noticeable effects other than having to reset the clock and the stereo head unit. I now use a maintainer over winter and I prefer that to disconnecting as I also believe it extends battery life compared to disconnecting for long periods.

 

[muzz]

Many Thanks for the responses

 

[944Turbo]

There was discussion on titanic a good few years back that the S2 should be left to tick over after reconnecting the battery for about 10 mins and t does some reving learning during this time, not had an s2 so not sure how true this is,
Tony

 

[Diver944]

Tony is right, here is a direct excerpt from the S2 owners manual -

"If the battery of the 944 S2 is disconnected, the data for the engine electronics stored in the control unit are erased. When the battery is reconnected, the engine must be run for approx 10 minutes to allow the control unit to re-acquire this data. During this period, the engine may idle unevenly or too fast."

I doubt that it would cause damage to just connect the battery and drive off but it will help set the idle speed accurately.

 

[TTM]

ORIGINAL: Diver944
"If the battery of the 944 S2 is disconnected, the data for the engine electronics stored in the control unit are erased. When the battery is reconnected, the engine must be run for approx 10 minutes to allow the control unit to re-acquire this data. During this period, the engine may idle unevenly or too fast."

I take it that whenever someone reconnects the battery on their S2, that is for running it (for at least 10min) after having reconnected it? [8|]

 

[944 man]

The S, S2 and 968 have a slightly more advanced DME than other models, but theres a gulf between having a few variable parameters and fully resetting the ECU like you would on a modern car (although that can be a very useful thing).

 

[muzz]

there are rough idle problems when cold and idles fine when hot, so it may have a learning problem.