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2.9 V6 4x4 Low idle while rolling to a stop. Standstill fine. Also over cooling.

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Old 17-12-2015, 05:37 PM
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Graham S1
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Default 2.9 V6 4x4 Low idle while rolling to a stop. Standstill fine. Also over cooling.

Suggestions for fixes please?

I'm pretty sure the over cooling is leading to the first problem. When running around twon etc, the gauge never gets above the top of the white block at the bottom of the gauge. If on a long run (ie motorway), it will drop to the bottom of the white block.

Viscous fan spins freely, not seized. There is a thermostat in there (put a new one in just in case while housing was off).

Replaced the VSS, but no change there.

Car is also a bit lumpy pulling away hard, or going up hill.

What else is there to check / look for. Car was serviced fully not long after I bought it a few months ago.
Old 18-12-2015, 10:55 AM
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dojj
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2 very easy things to check/change

First is the temp sender, once they go past a predetermined level they never read right again so change it, they are around £11 from ford but you need to get the correct one for your car, not based on what the colour ring is at the top

Secondly, remove the air box so that you can access the flaps inside the air flow metres, push these flaps with your fingers to check for any resistance or unevenness in the movement

You shouldn't be able to plug then back in the wrong way either but don't discount that
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Old 19-12-2015, 03:49 PM
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Cheers Dojj

Originally Posted by dojj
First is the temp sender, once they go past a predetermined level they never read right again so change it, they are around £11 from ford but you need to get the correct one for your car, not based on what the colour ring is at the top
The coloured ring sender is for the dash, yes? That won't make any difference to what the engine does? The big fat one next to it is for the ECU?

Originally Posted by dojj
Secondly, remove the air box so that you can access the flaps inside the air flow metres, push these flaps with your fingers to check for any resistance or unevenness in the movement

You shouldn't be able to plug then back in the wrong way either but don't discount that
Flaps move nice and freely. When I first bought the car and gave it the once over, one of the flaps was stuck solid. Had the unit apart, and got some lubricant into the spindle, so now it moves and springs back easily. White plug in the front meter, black plug in the rear one.
Old 20-12-2015, 09:44 PM
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If the temp on the dash is wrong it can give you thoughts of stuff going wrong that might be fine
If anything they tend to run hot with the viscous fan

The flap issue might still be the cause, get a meter on there to see if it's working properly rather than just moving freely, the tracks can cause issues

Unfortunately you can't put a fault code reader on then
Old 24-12-2015, 02:01 PM
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Ha! And duurrrrrr....

Forgot I hadn't rechecked CO after rebuilding the top end a few weeks ago. Was reading minus figures on the CO meter. Wound the screws out a bit, which made it worse. Wound them all the way back in until they stopped, and CO went to 1.2% ish which isn't too bad. This has now stopped the near stalling, so it was probably running way too rich.

Anyhoos, seems to be fixed now. Be interesting to see if theres an improvement to mileage, was only getting about 270 out of a tank.
Old 24-12-2015, 04:18 PM
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As much as that!!!!
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