Disconnect battery or not?

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Coldcut

New member
Joined
Jun 26, 2016
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96
I've just changed my coil and I've got to change the tps the weekend.
Should you disconnect the battery at all when changing these parts?
Not for safety, i mean does the ecu reset itself and notice a change if one was faulty?
My car has been driving like it's running on 3 cylinders.
Plugs and leads are good but it has the original coil and tps on it still and the revs fluctuate so i thought changing the ttps would sort that.
Oil on plugs, well in cylinder 1,so changing rocker cover gasket the weekend to sort that issue out.
Also is it easy enough to change the tps as there isn't much room.
 
Coldcut said:
[post]353810[/post] Should you disconnect the battery at all when changing these parts?
Not for safety, i mean does the ecu reset itself and notice a change if one was faulty?
Never a bad idea to disconnect the negative battery lead when working on anything vaguely electrical in a car. After the battery has been disconnected for between 1 and 2 hours the ECU will clear any error codes. If you go down this route then make you know your radio code before disconnecting the battery and also perform the 'battery off ECU learning curve' after it's all back together, i.e. -

3 minutes at idle, then let it warm up, (er, by letting it idle some more!) then 2 minutes at 1200rpm (using your foot on the accelerator to keep it at a constant 1200 rpm.) Then a 5 mile trip of normal driving and you're done.

The result of not doing a 'battery off ECU learning curve' reset on a Puma can range from almost no discernible difference to normal or to violently kangarooing up the road for half a mile with the brakes full on feeling, which then improves but the car then runs like some old granny car...or anywhere inbetween those two extremes.

I would do the above but, alternatively, you could leave the battery alone and clear any error codes using just a OBDII scanner or reader with Torque/Forscan software on tablet/laptop.
 
Cheers Frank, i have never heard of the battery off ecu learning curve.
Thanks...
 
TIS Official ECU reset procedure:
Disconnect battery for 1 hour:
Ford Technical:
After reconnecting battery, engine should be allowed to idle for 3 minutes, as stored idle and drive values contained within the powertrain control module have been lost. This may cause a driveability concern if the following is not carried out.
Once engine reaches normal operating temperature, revs should be increased to 1,200rpm and maintained for approximately 2 minutes. This will allow powertrain control module to relearn idle values. For powertrain control module to complete its learning strategy, vehicle should be driven for approximately 5 miles of varied driving.
 
I am doing some rust work next year. What is this Bilt hamber stuff? I was going to wax oyl inside sills and doors.
 

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