Temperature guage bouncing - LPG related

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klu99apm
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Post Mon Feb 20, 2006 4:43 pm

Since Friday when my car is run on petrol the temperature guage swings between the actual temperature and blue. When the car is running on LPG it works perfectly.

I've taken the dash out today and tightened the nut behind the temperature guage just to rule it out but it hasn't sorted the problem :-x

All I can think of is that its to do with when the injectors are disconnected to run on LPG its interfering with something, but I've no idea really!

Any ideas anyone?
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klu99apm
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Post Tue Feb 21, 2006 5:05 pm

Ok I've been PM'ing Brianmoooore about this but thought I'd post in the technical forum as other people might know the answer to my questions and I want to try and stop bugging Brian by PM'ing him :)

Brian has ruled out the interaction of the LPG/Injectors being the problem and has suggested that maybe I've disturbed an earth somewhere near the glovebox.

1) Is this where the instrument cluster gets its earth?

2) The only earth down here I've found is the one in the following photo. Is there any more hiding somewhere?

Image

Thanks for any help!
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klu99apm
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Post Tue Feb 21, 2006 5:24 pm

Ok final question for today about this topic hopefully!

I think the wiring for the temp sensors goes through the plug in the photo. So I wanted do give it a clean and spray it with some silicone afterwards...

How does it come apart? I can turn the plastic collar underneath but can't seem to pull it apart. Do I need to pull harder or does it twist or something? (Its not the problem as the guage works fine on petrol but its bugging me thats all :) )

Image

Thanks again!
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Brianmoooore
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Post Tue Feb 21, 2006 7:58 pm

klu99apm wrote:Ok final question for today about this topic hopefully!

I think the wiring for the temp sensors goes through the plug in the photo. So I wanted do give it a clean and spray it with some silicone afterwards...

How does it come apart? I can turn the plastic collar underneath but can't seem to pull it apart. Do I need to pull harder or does it twist or something? (Its not the problem as the guage works fine on petrol but its bugging me thats all :) )

Image

Thanks again!
You may have found the answer to your problem! Didn't think about that socket when I answered the PM, but the common feeds to the injectors and the temp gauge wire do go through here.
Aconstant 12V supply will be present on two pins in this connector, but not when on LPG.
Wonder if there is corrosion in this connector that is causing this voltage to leak across and affect the temp gauge readings.
The connector is similar to the diagnostic connector in construction.
Twist the knurled part of the socket anticlockwise and pull apart at the same time, downwards. The plug will be left fixed to the black metal bracket, held in place by a lockring
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klu99apm
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Post Tue Feb 21, 2006 8:03 pm

Thanks Brianmoooore!

Will have a go at this plug tomorrow then. Maybe that will be the end of the problem - fingers crossed :)