Disconnecting battery on Focus (resetting computer)

bushmins

bushmins

bushmins

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If i take the terminals off the battery will the computer loose any ECU updates?

Im having a bit of a problem when reving the engine. When it gets to about 2500 rpm there is a slight 'glitch' where the engines revs will jump about abit, when i press the excellerator a bit more it will eventually jump up to 3000 rpm.

I cant feel the rev thing when driving and ive tested it to the hills, it only happens when im reving in netural.

I was thinking maybe reseting the computer might fix it but i dont want to loose any up dates.
 
Are you talking about custom maps or updates applied by your dealer? Either way, these should be flashed in to the ECU, meaning that disconnecting the battery for a prolonged period will not lose any updates/maps applied to the ECU. For the bits that the car 'learns' by itself, this is normally wiped by leaving the battery off for a while but yours may be different, I don't 'do' fords ;).
 
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I think disconnecting the power overnight will reset the ECU to default (inc a previous remap) & should be done if changing something like an air-filter etc. but yours may be different, I don't 'do' fords ;).
The blip in standing revs may be normal anyway, especially with a remap.

As the Americans say: If it ain’t broke dont fix it!
 
I cant feel the rev thing when driving and ive tested it to the hills, it only happens when im reving in netural.
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I would sell the car, not being able to rev the engine smoothly in neutral is a serious problem! :confused:
 
I did this on my Focus and it didn't wipe my remap. It only wipes the parts it has learned through driving. However I found out later, that the TDCi ECU doesn't reset like the petrol ECU anyway..

Might be worth getting yourself on the FFOC forums, they've been a helpful lot while I had my Focus! :)
 
Disconnecting the battery for 20mins will reset it. The information 'learned' will be lost and naturally the radio needs its code popping back in. The Ford ECU cant change as much as say a BMW ECU can anyway so it will have adjusted itself less. If you have a map, that will be fine. As for the rev problem. I think one of the holes in the torque on my zetec is at around 2500 but that isn't to say it stops reving or you would notice it in neutral. A quick reset is the best place to start with diagnosing this.
 
G_D said:
Disconnecting the battery for 20mins will reset it. The information 'learned' will be lost and naturally the radio needs its code popping back in. The Ford ECU cant change as much as say a BMW ECU can anyway so it will have adjusted itself less. If you have a map, that will be fine. As for the rev problem. I think one of the holes in the torque on my zetec is at around 2500 but that isn't to say it stops reving or you would notice it in neutral. A quick reset is the best place to start with diagnosing this.
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Why on earth would you spend time and effort diagnosing something that does not manifest itself whilst using the car normally i.e. driving it!? :confused:
 
There is a problem, don't these usually need fixing? Also he came on here for help. Saying "ohh never mind it does not happen when driving along" is not answering his question or solving his problem. Also just because it is happening whilst stationary now doesn't mean it wont manifest itself into a larger problem later though, better to solve it now before it becomes a bigger issue no? Also if this is something than can be fixed so simply as by disconnecting 2 wires for a few minutes why not do that?

Im sorry but if your not interested in helping then fine, read a different thread there are plenty to chose from and leave someone else to try and possibly help.
 
CaPtBlaCk said:
Why on earth would you spend time and effort diagnosing something that does not manifest itself whilst using the car normally i.e. driving it!? :confused:
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Like G_D said. Its a learnt behaviour thing. When youve had lots of experience with things that dont quite work as they should or you have a suspicion something is not quite right its best to get them checked out before it goes totally wrong.

Im thinking ill go see if a Ford tech can have a quick look at it.
 
G_D said:
There is a problem, don't these usually need fixing? Also he came on here for help. Saying "ohh never mind it does not happen when driving along" is not answering his question or solving his problem. Also just because it is happening whilst stationary now doesn't mean it wont manifest itself into a larger problem later though, better to solve it now before it becomes a bigger issue no? Also if this is something than can be fixed so simply as by disconnecting 2 wires for a few minutes why not do that?
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I would suggest that there is no problem with an engine that drives fine i.e. under load. Accelerating an engine without load is not a normal operating condition, hence what learnt behaviour would the ECU pick up that can be rectified by the re-learning process......?

Im sorry but if your not interested in helping then fine, read a different thread there are plenty to chose from and leave someone else to try and possibly help.
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LOL at the keyboard mechanic! :D
 
bushmins said:
Like G_D said. Its a learnt behaviour thing. When youve had lots of experience with things that dont quite work as they should or you have a suspicion something is not quite right its best to get them checked out before it goes totally wrong.

Im thinking ill go see if a Ford tech can have a quick look at it.
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Your money, your time.......by the way is this a TDCI?
 
as others had said..... whats the problem? why would you need to rev over 2500???

Unless your part of a Racing team?

if it did that while driving id say it was the coil pack, mine went and getting it over 2500 was a right PITA.... Id HAVE to drop a cog to get it over 2500 upto 3500 before i could accelerate more :p:o
 
Dont really need to rev at all, it was something i noticed. It was a worry as I just got the car (04 model 1.6 petrol).

Im sure it will be alright... Watch this space :)

Thanks for all the advice.
 
bushmins said:
Dont really need to rev at all, it was something i noticed. It was a worry as I just got the car (04 model 1.6 petrol).

Im sure it will be alright... Watch this space :)

Thanks for all the advice.
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not sure if your focus model has "test" mode on its dash at all, normally you hold in a button while turning the key to "ON" (not start) hold the button in till test mode shows.

this then lets you cycle through lots of info and, maybe the DTC's which would display any faults you might have.
 
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