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ian d

New Member

• Feb 6, 2011

• #1

Hi need some help my 98 4.0 v8 disco 1 wont idle right when driving it revs to high until you stop then seams to settle down to normale idle , also seems to be very heavy on fuel at the moment any body got any ideas ? thankyou

 

njh2

Active Member

• Feb 7, 2011

• #2

Can you re-expalin the problem a little better, is it auto or manual?

 

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ian d

New Member

• Feb 7, 2011

• #3

It was auto now manual . When i start up it revs high for a bit then ruturns to idle , problem is as soon as i start driving between each gear change it revs high between 1500k to 2000k and dosnt return to correct idle until i pull up and stop , as soon as i pull away and continue driving revs lift between each gear change again . Problem may have been there when it was auto but didnt have to change gear then so didnt notice it .

 

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fyne1

Active Member

• Feb 7, 2011

• #4

when conversion was done did you fit clutch switch to system and was ecu changed or re-flashed?

 

fett

Well-Known Member

• Feb 7, 2011

• #5

stepper may be sticking

 

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ian d

New Member

• Feb 8, 2011

• #6

Re clutch switch if you mean for the park senser yes i fitted a switch . I have also re sealed the plenum and checked for leaks , checked all pipes to the plenum for leaks , replaced the idle stepper and the ecu temp sender and i have tryed a new air flow meter from a freinds disco that he has just replaced himself . I also replaced ecu yesterday it was from another auto unfortunatley but it has sorted one problem the emissions are now spot on but still revs high .

 

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fyne1

Active Member

• Feb 9, 2011

• #7

Cant remember seeing factory v8 manual but the td5 version has a clutch switch in line or cyl, this cuts the revs when clutch pressed.

 

discool

Well-Known Member

• Feb 12, 2011

• #8

fett said:

stepper may be sticking

Click to expand...

The so called 4.0 V8 don't have one

 

discool

Well-Known Member

• Feb 12, 2011

• #9

ian d said:

Re clutch switch if you mean for the park senser yes i fitted a switch . I have also re sealed the plenum and checked for leaks , checked all pipes to the plenum for leaks , replaced the idle stepper and the ecu temp sender and i have tryed a new air flow meter from a freinds disco that he has just replaced himself . I also replaced ecu yesterday it was from another auto unfortunatley but it has sorted one problem the emissions are now spot on but still revs high .

Click to expand...

The so called 4.0 V8 don't have one

 

discool

Well-Known Member

• Feb 12, 2011

• #10

ian d said:

Re clutch switch if you mean for the park senser yes i fitted a switch . I have also re sealed the plenum and checked for leaks , checked all pipes to the plenum for leaks , replaced the idle stepper and the ecu temp sender and i have tryed a new air flow meter from a freinds disco that he has just replaced himself . I also replaced ecu yesterday it was from another auto unfortunatley but it has sorted one problem the emissions are now spot on but still revs high .

Click to expand...

Thats difficult as the so called 4.0 doesn't have one or do you have a 3.9? .
With a 3.9 you can adjust the base idle and then the engine ECU will look arfter the rest

 

Mr Noisy

Coming in your ears.

• Feb 13, 2011

• #11

If it revs too high the ignition could be over advanced.

This is assuming you do actually have a 3.9 !

 

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ian d

New Member

• Feb 13, 2011

• #12

Sorry have a habit of rounding things up its a 3947cc

 

vougese39

Well-Known Member

• Feb 13, 2011

• #13

Is it a d2 pr a d1 you will need to fit a manual resister if it is a d1 and reset the base idle and clear all the ecu faults

If it is a d2 then you will need the clutch switch and need the ecu resetting with testbook