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Discussion Starter · #1 ·
Well i decided to try it out since my clock needed to be adjusted for daylight saving anyways. I have disconnected the negative battery terminal and intend to leave it over night hoping that the computer will re-learn.

Should i just reconnect it after one night or should i reconnect it when i actually want to drive it.

Thanks in advanced..
 

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Just becarefull doing this. Not long ago I had to have my battery replaced and I got talking to the tec. He claimed that they have had some problems with Fords especially the AU when you go to restart the engine after having the power disconnected. On the initial restart the engine goes to max rpm and stays there for a short period. The rev limiter seemed not to work in this period.
 

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You shouldn't connect the battery till you want to drive it.

I've never seen this on a AU going past rev limiter but there is a special way to start a AU when jump starting to stop frying the ecu. this might useful to somebody maybe??
When your ready to start the car,, with jumper leads (one of earth one on positive). have a small wire made up with small male splade clip at each end of it.
pull the cover on the relay box under bonnet. have key to ignition/engine off. There is... five replays in the box near battery? pull the top left, then you put the wire you have with splade clips, one end into the top hole and the other end into the bottom hole of the relay thats removed, should jump the car. Easy but hard to explain.
 

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Discussion Starter · #5 ·
Yeah i won't be driving it till Wednesday, so i'll connect it back up then.

With my experience of disconnecting the batteries in falcons is that the idling goes funny for the first few km's. I guess this is because the computer is re-learning.

When i'm driving after re-connecting the battery, is it true that i have to drive it hard, if so should i take it to redline (once engine is warm) or should i just drive normally?
 

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XLR8 said:
your normal driving is taking it to the red line:s5 :s5 :s5
I was going to suggest that if your normal habits aren't to take it to the redline, they should be quickly altered, but it doesn't seem that I have to suggest this after all ;) :D
 

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Discussion Starter · #8 ·
DONUT KING said:

I was going to suggest that if your normal habits aren't to take it to the redline, they should be quickly altered, but it doesn't seem that I have to suggest this after all ;) :D
Must admit i go close at times but not right at it, me needs the EF to last. :s4
 

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EF_Falcon_GuY said:
Well i decided to try it out since my clock needed to be adjusted for daylight saving anyways. I have disconnected the negative battery terminal and intend to leave it over night hoping that the computer will re-learn.

Should i just reconnect it after one night or should i reconnect it when i actually want to drive it.

Thanks in advanced..
What was your original problem?

In order for the computer to return to factory settings, ie reset the KAM (keep alive memory) you only need to have the battery disconnected for about 5 minutes.
Reconnecting the battery does not start the relearn process. Once you start and drive the car, the short and long term fuel trims start "learning".
 
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HSE2 said:
Just becarefull doing this. Not long ago I had to have my battery replaced and I got talking to the tec. He claimed that they have had some problems with Fords especially the AU when you go to restart the engine after having the power disconnected. On the initial restart the engine goes to max rpm and stays there for a short period. The rev limiter seemed not to work in this period.
The above is not possible.
The engine cannot go to max revs with a closed throttle.

EF falcon guy;Listen to mbrown 42, he's hit the nail on the head.

Pete.
 

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Discussion Starter · #11 ·
Yeap seems mbrown42 is right, i'll re-connect the battery tonight. Then i'll take it for a spin. :s1 :s1
 

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XR9UTE said:


The above is not possible.
The engine cannot go to max revs with a closed throttle.

EF falcon guy;Listen to mbrown 42, he's hit the nail on the head.

Pete.
Norco batteries were the company that were involved. I know they contacted Ford about it. They now connect a slave to every AU that they change the battery on which is why I found out when they tried to climb into the cabin to remove the lighter. I agree it doesn't sound right, I thought so at the time, but these guys were deadly serious about it so if it isn't possible they are going to alot of trouble just to save the stereo settings.

I don't know under what circumstances they found the rev limiter to not to be working, but the battery change was what was blamed.
 

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HSE2 said:

Norco batteries were the company that were involved. I know they contacted Ford about it. They now connect a slave to every AU that they change the battery on which is why I found out when they tried to climb into the cabin to remove the lighter. I agree it doesn't sound right, I thought so at the time, but these guys were deadly serious about it so if it isn't possible they are going to alot of trouble just to save the stereo settings.

I don't know under what circumstances they found the rev limiter to not to be working, but the battery change was what was blamed.
Unless the throttle cable is disconnected and the return spring on the throttle body is also broken, it is NOT physically possible for the engine to rev to the limiter (~5700rpm) because the engine cannot get enough air to rev (because of the throttle butterfly being closed)
If the idle air control was (for some unknown reason) open more than it should be for startup situation, maybe the revs would be up slightly but certainly not above say 1500rpm.

The reason for the memory minder in the cig. lighter is so the radio security code isnt lost. Most people have either lost their codes or it's just too much hassle getting it from the dealer again.
 

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mbrown42 said:


Unless the throttle cable is disconnected and the return spring on the throttle body is also broken, it is NOT physically possible for the engine to rev to the limiter (~5700rpm) because the engine cannot get enough air to rev (because of the throttle butterfly being closed)
If the idle air control was (for some unknown reason) open more than it should be for startup situation, maybe the revs would be up slightly but certainly not above say 1500rpm.

The reason for the memory minder in the cig. lighter is so the radio security code isnt lost. Most people have either lost their codes or it's just too much hassle getting it from the dealer again.
How I originally posted it is practically word for word with what I was told. I suspect what they meant was that when the owner tried to rev the car they found they had no limit. Both the cars went back to the dealership. They also went to the trouble of saying the problem was only on some 6 cylinder AU versions that they had serviced.


Since I have had the exhaust changed my car revs to about 2200 on start up. No throttle. Only since the exhaust was changed. The whole neighbourhood can hear it, I mean it really sounds loud when it starts. Goes off with huge rush, but this is off the subject.

Personally my only experience with engine management under low voltage or strange battery charge tends to send the engine running the other way. Struggling to idle and stay running like it is real lean.

Yeah I know about the radio security but THIS wasn't the reason they did it. I told them not to worry about the radio it was only when I told them it was an 8 that they decided not to worry and then that was only after the two of them had a conversation about the subject. Trust me these guys were really serious about the engine management. They have always carried out my battery work and they have always seemed to know what they are on about. One thing for sure is that they believe there is a problem and I don't think if I were to tell them they were imagining it they would believe me. I mean they wouldn't carry on about it if they didn't fully believe there was an issue would they? And I mean they did carry on too.
As both you and Pete have said it is impossible to happen so I must of misunderstood the exact circumstances but like I said they really don't take the power off AU 6 cylinder cars because of what has happened to them in the past.
And yes these guys usually ask if you have the stereo codes and if you have they don't bother saving the info with the slave.
One of the cars I look after from time to time has to have the power supply maintained as even the windows and sunroof have memories for anti jambing functions that are a pain in the ass to reset.
 

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hmm last time the battery died in our EB s2 (EECIV i think) the damn thing went crazy, wouldnt idle or anything
we tried disconnecting it so it could re-learn etc, but it just wouldnt, the pplz at dealership spent days trying to fix it and finally just re-set it one more time and it worked hehe

but i just changed the battery the other day and its still going :)
 

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I have been told that you have approximatly 10mins before the ECU will loose it memory.

Also conecting a proxy battery eliminates power surges while connecting and disconnecting terminals, because the voltage is equal, and saves scuraging for the elusive radio code.

Aparently there is a procedure to follow to help the ECU re-learn. Something like, slowly eccelerate to 20Km/h then stop, then slowly up to 60Km/h, up to 150Km/h, after that quickly eccelerate to 60Km/h. That not the right way but an example. I heard this in a TAFE course i did.
 

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Ok the other issue when you have no battery for a while is that the transmission has to relearn the shift points and throttle calibration if you have a BTR auto trans LE 85/95 and a M89/95 ECU. This is why the car will often not idle correctly after losing the battery. To reprogram to the default set up the process is as follows:

Ignition on
Engine off
Move Trans Lever to Manual 1
Switch to economy
Move lever to Manual 2
Switch to Performance
move lever to Manual 3
Switch to economy

Following this sequence the mode indicator light will flash when the STI trans terminal st the diagnostic connector is grounded. Code 99 will display until this closed throttle calibration is complete.

The foregoing applies to EA/EB/ED; I'm not sure about subsequent models.
 
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