Engine Will Not Idle

[headnut]

Hiya All,

 

Got a 1995 galaxy mk1 2.8i ghia for the last 9 mths it has been stored on the drive and not used teaching son to drive so been using his car.

 

It is now due an mot which I have booked for tomorrow I have charged the battery so all is ok there but she will not idle im guessing the ecu has lost its settings so how do I reset this.

 

It is an automatic so running it will be a problem until I get on motorway is there any other way.

 

Oh and as it has been off road for 9 mths is there anything else i should be checking

 

Thanks

 

HEADNUT

[sepulchrave]

Hmm, it should idle nonetheless.

 

Maybe your throttle body stepper has seized up through lack of use, try good ol' WD40 on the motor spindle and throttle spindles.

[headnut]

Ok an update on this issue.

 

parked the gal up for 4 days as was not needing it and battery went flat so I charged it up and put it back on.

 

Engine was turning over but would not start so I took the battery back as it was only 18 mths old they tested it and came back and said that it was not delivering enough amps so they replaced it great I thought.

 

So went home fitted replacement battery and it started first time but the issue i had before reappeared the car will not idle and is a real pain driving an auto that will not idle dangerous too.

 

Last time after taking the car for a long drive of 100 miles the engine ecu seemed to reset it self and all was ok now that problem has come back surely you should not have to do this every time you disconnect the battery.

 

Could the engine ECU have a fault?

 

Is there anyone near me that could do a vag-com test for me?

 

This is driving me nuts now as it is a lovely car to drive, but im scared to drive it while it does not idle.

 

Any help would be greatly recieved.

 

Regards

 

Headnut

[headnut]

Ok an update on this issue.

 

parked the gal up for 4 days as was not needing it and battery went flat so I charged it up and put it back on.

 

Engine was turning over but would not start so I took the battery back as it was only 18 mths old they tested it and came back and said that it was not delivering enough amps so they replaced it great I thought.

 

So went home fitted replacement battery and it started first time but the issue i had before reappeared the car will not idle and is a real pain driving an auto that will not idle dangerous too.

 

Last time after taking the car for a long drive of 100 miles the engine ecu seemed to reset it self and all was ok now that problem has come back surely you should not have to do this every time you disconnect the battery.

 

Could the engine ECU have a fault?

 

Is there anyone near me that could do a vag-com test for me?

 

This is driving me nuts now as it is a lovely car to drive, but im scared to drive it while it does not idle.

 

Any help would be greatly recieved.

 

Regards

 

Headnut

[Dave-G]

I don't know if this helps but I read something like it on another non galaxy forum.

 

To re-boot all ECU's....

 

Turn ignition on without starting the engine, turn off everything that you usually leave on like interior/door/side lights, radio, fan etc. Remove posititive cable from the battery and short it out to the engine to clear all traces of power from all systems.

 

Turn off ignition.

 

Reconnect battery and leave for a few minutes wthout turning anything on.

 

Turn key to ingition only with nothing else turned on for a few minutes.

 

Start engine without revving it for a good few minutes to let the ECU's learn whats what again.

 

 

 

Hope that is usefull but please check it's right before you do it on your car. This is offered with best intentions but please do not flame me if it's incorrect.

 

ATB, Dave.

[sepulchrave]

Unfortunately you are rebooting the ECU each time you allow the battery to die, therefore the ECU has to start completely from scratch with all the settings which will be unique to your engine.

 

Sometimes a flat battery will 'glitch' the ECU when you try to start the car due to the sudden drop in voltage as the starter solenoid engages which then rises back high enough to repower the ECU when you release the key. This can scramble the settings in the ECU, but not the default map because that is in firmware.

 

Your car should idle on the default map, generally it will idle fast until the ECU resets the settings after which it should drop back to a rock steady 750 rpm. Have you checked the throttle body, it could be sticking, therefore the stepper cannot adjust the idle. When you took it for a drive the throttle possibly freed off through use but has now stuck again.