Temp gauge..odd showings..

[anders]

Hello all

My first post here... great forum by the way.

My temp gauge is showing some odd readings. When i start my car (from cold engine) the temp needle jumps straight way to 12 o'clock and works its way to 2 o'clock as engine getting warmer.

When i disconnect the coolant temp sensor it shows Zero. Then laying the sensor at a hot spot on the engine it straight away jumps tp 2 o'clock again.

Im i dealing with a faulty coolant temp sensor here ? Its getting pretty funny to drive without knowning how hot your engine is.

Anyone else seen that kind og error before?

my car is the bmw e34, 2,5 - 1988

Regards

/Anders

[DaCan23]

Possible instrument cluster issue, find out if your SI board has batteries that tend to fail after 15+ years.

http://www.programainc.com/files/03_2006_Instrument_Clusters.pdf

[632 Regal]

possible yes, I would replace the sensor first.
order parts from www.bmaparts.com



Possible instrument cluster issue, find out if your SI board has batteries that tend to fail after 15+ years.

http://www.programainc.com/files/03_2006_Instrument_Clusters.pdf

[shogun]

Possible instrument cluster issue, find out if your SI board has batteries that tend to fail after 15+ years.

http://www.programainc.com/files/03_2006_Instrument_Clusters.pdf

E34 do not have SI batteries anymore like the older models E30 and E28.
They have capacitors.
But capacitors also fail after 15 years or earlier
http://bmwe32.masscom.net/johan/dash_caps/dash_caps.html

[anders]

might have to say the problem was showing after i replaced my top during overheating... i gotta new top and also replaced the rest above the top...

The rest og my gauges works fine..

[Blitzkrieg Bob]

on the water neck.

Could they be mixed up?

[anders]

No the cylinder head gasket was replaced because the old one blowed... then i also got a new air intake manifold, tstat housing and so on,,, engine parts where taking from en e30 m20 2,5 1988. So got all new gear from a e30 engine from the head gasket and above

[anders]

Blitzkrieg Bob:

I will look that up.. and try to look for them to possible be switched

and because af the gague failure i also constantly getting messages that engine is overheating... very very irretating

[Blitzkrieg Bob]

who went through something like this and after all the work, it turned out to be mixed up high temp and low temp sensor on the water neck T stat housing.

Good luck

[anders]

Blitzkrieg Bob:

Can u tell the line up by color... i know one og them are blue and i think one og them are brown.. is it the two most outer sensors we are talking about?

[Blitzkrieg Bob]

they are right up there next to each other, so sometimes after a head job they get mixed up.

[anders]

sensors wasnt switched.. both is sitting i the right spot.

I can switch the plugs around, but then the car runs bad.

Wonder what is going wrong here... Could it be bad grounding...

Please,,, help me on this.. right now i run the car with temp gauge unplugged and have no temp indicatiion in car. If i plug it in.. it will have its start position at the ½ mark and then go to full/red mark when reaching operating temp. Very irretating... as im constantly getting engine overheating errors on my dashboard display.

I tried to switch temp sensor to another used one. Problem is stille the same. Could both sensors i tried be faulty or have it something to do with other stuff....