Coolant temperature gauge problem.

I have '88 e30 316, and a problem with my temperature gauge. When I start my car it starts to go out of blue area, and then it starts to jerk to left or right. Car was not driven for ~7 years, and as I
remember it used to sit vertically when engine is at normal running temperature. Now it is about half way from blue to vertical, and jerking from time to time.
I changed dash panel recently with a used one, and it still jerks. Yesterday I changed temp sending unit - still jerks.
Perhaps there is some bad contact somewhere. I wanted to test it with my old dash panel, but I can not figure out which wire to connect to what. I have Haynes, Bentley and some German manual for e30 and none helped.
I took dash panel apart and it seems that one connection goes to the blue connector pin 26, and other two (ground and other connection of the temp gauge) go to the board that controls green, yellow and red service lights.
Can anyone tell me color code of the wire where to connect +12V, where ground, and where temp sender?
Or perhaps this is some common fault and known solution?
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/__/ / \ ** Registrovani korisnik Linuksa #291606 **
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Hi.
Had same problem,was down to a poor earth on the temperature gauge.Remove dash and clean earth contact on rear and tighten.
Hope this helps
Mark

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Nedavno spectrum pise:
| Had same problem,was down to a poor earth on the temperature | gauge.Remove dash and clean earth contact on rear and tighten.
I will try that, thanks. But I changed dash panel (with second hand unit), and my problem is still there.
I was wondering, since ground and one of gauge connectors go to the service indicator lights board, could it be that that board is bad and the source of my problems? I changed original dash panel because of that board failing (red light lit, even with two new batteries).
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Nedavno spectrum pise:
|> I have '88 e30 316, and a problem with my temperature gauge. When I |> start my car it starts to go out of blue area, and then it starts to |> jerk to left or right.| | Had same problem,was down to a poor earth on the temperature | gauge. Remove dash and clean earth contact on rear and tighten.
Just for the record, I tried this today. I completely removed temp gauge from the instrument cluster, cleaned all contacts, sprayed with contact cleaner - but nothing, problem is still here.
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Nedavno Yvan pise:
| |> I have '88 e30 316, and a problem with my temperature gauge. When I | |> start my car it starts to go out of blue area, and then it starts | |> to jerk to left or right. | | | | Had same problem,was down to a poor earth on the temperature | | gauge. Remove dash and clean earth contact on rear and tighten. | | Just for the record, I tried this today. I completely removed temp | gauge from the instrument cluster, cleaned all contacts, sprayed with | contact cleaner - but nothing, problem is still here.
Actually, Mark was right. I removed temp gauge. It has three contact point's. I used three wires and soldered connection points to the board. Jiggling stopped.
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Dunno if there's a relation but I've had issues with the fuse box on my 1991 E30 316i. Cold solderings, I had to rework a lot of them. OTOH, if the car hasn't been used for 7 years, the thermostat might be unstable, randomly stucked. But again, slow variations (minutes or more) not jiggling.

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