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Tue Mar 22, 2011 8:12 pm

Hello fellers, to start, I've searched but having been able to find an answer to the problem that I'm still having.

I've have a new oil temp gauge, and as you can see in the first picture, (CB performance stuff) I had the wire going to the gauge from this spot.. NO GOOD..
I then saw a link where GLENN had installed the sensor on the oil filter mount, and as you can see, I did the same.. NO GOOD.. I'm stumped, if I take the wire off the sending unit and ground it, the gauge goes all the way to the right... Brand new sensors, gauge and wiring.. Any idea?? Thanks in advance.

Tue Mar 22, 2011 8:22 pm

When everything is hooked up and your turn the key on, does the gage move slightly? How long did you let the engine run before you assumed the gage was not working? With full cooling , it takes a little run time to get the needle to start reading temp. That is not the ideal spot for the sending unit anyway but you will still get some reading.

Tue Mar 22, 2011 8:22 pm

Check the resistance of the sender cold then drop in to boiling water and quickly check the resistance again. Should be hi res cold and low resistance hot. As it cools the res should climb back to the cold reading. Either the sender is bad or the wire is.

RC

Tue Mar 22, 2011 8:36 pm

Is the engine grounded at that OT sender location? It needs to be.

Tue Mar 22, 2011 8:41 pm

Can't be the wire if grounding it sends the gauge to high Paul.. I think the sender is probably the cause of the problem.. A resistance test would indicate what the sender is doing.

Tue Mar 22, 2011 8:57 pm

mharney wrote: Can't be the wire if grounding it sends the gauge to high Paul.. I think the sender is probably the cause of the problem.. A resistance test would indicate what the sender is doing. I thought he meant grounding at the gauge....but I admit I read it real fast with not too much thought..... :shock:

Tue Mar 22, 2011 9:17 pm

I have the same gauge. It takes at least 5 minutes of good driving before it registers. The gauge reads low, it barely gets up to 180, I think it has to do with the location of the sender.

Tue Mar 22, 2011 9:19 pm

speedyshift74 wrote: When everything is hooked up and your turn the key on, does the gage move slightly? How long did you let the engine run before you assumed the gage was not working? With full cooling , it takes a little run time to get the needle to start reading temp. That is not the ideal spot for the sending unit anyway but you will still get some reading.

First, Thanks to all for the quick replies. Yes sr. the needle moves slightly when I turn the key to the accessory position.... I'm not sure why you say that "this is not the ideal spot for the sending unit"? I have two sending unit, one at the engine and the second on the oil mount.. If these two spots are no good, can you enlighten me as to where it would be a better spot.. Graz

I ran the car for about 30 minutes on the freeway and nothing.. Both sensors are brand new... The bigger on is from CB and the other one on the mount is from CIP1..

Wed Mar 23, 2011 12:06 am

I asked if the gage moves slightly when you first turn the key on to indicate the gage is getting power to it. When you disconnect the sender and turn on the key it should peg. I use the front relief valve plug for my temp reading location. It dont really matter where you take your readings from though. Its all personal choice. Is that the sending unit recommended for the gage? I know you cant mix or interchange gage and sending units in some cases. Looks like its time to break out the meter and check some resistance.

Wed Mar 23, 2011 5:50 am

begood56vw wrote: I'm stumped, if I take the wire off the sending unit and ground it, the gauge goes all the way to the right...

so with no resistance (grounded) your gauge reads fully hot?

RockCrusher wrote: Should be hi res cold and low resistance hot. As it cools the res should climb back to the cold reading. RC

speedyshift74 wrote: When you disconnect the sender and turn on the key it should peg.

Should read full cold when grounded.

So the problem is with the gauge isnt it?
You have tried 2 senders and they both do the same thing, in 2 differant locations. The evidence presented indicates your gauge is reading backwards. Or at least backwards to the way other's, including mine, works. Which could also be a sender incompatability i suppose.

Wed Mar 23, 2011 7:58 am

According to this VDO document....

http://www.egauges.com/pdf/vdo/0-515-012-178.pdf

Key on, sensor wire grounded gauge should go full right (hot)... Exactly opposite of fuel gauge or oil pressure gauge (testing)...

With key on wire disconnected gauge should go full left (cold) ... Again exactly opposite of fuel & oil pressure gauge (testing)...

Dale

Wed Mar 23, 2011 11:16 am

I've got the recommended VDO Oil Temp, sender and "T" fitting from eGauge (used w/ a VDO pressure sender). Same problem. First sender was bad - no resistance change. VDO sent new one. Still no solution. I will check gauge as described in recent thread and get back. Ed

Wed Mar 23, 2011 11:45 am

Dale M. wrote: According to this VDO document....

http://www.egauges.com/pdf/vdo/0-515-012-178.pdf

Key on, sensor wire grounded gauge should go full right (hot)... Exactly opposite of fuel gauge or oil pressure gauge (testing)...

With key on wire disconnected gauge should go full left (cold) ... Again exactly opposite of fuel & oil pressure gauge (testing)...

Dale

That's were I got the info about taking the wire of the sensor and grounding it. This will make my VDO gauge neddle go to the right or HOT...I can't imagine both sensors being bad.. I haven't tried the resistance test since I don't have anything to check it with, but I figured since both of the sensors are from respectible companies (CB and CIP1) I thought I get luck...

At one time I had the wire going from the sensor to a block connector. I thought that since the VDO gauge was not working, the wire being connected to the block connector, it was causing a resistance. So I removed the wire from the block connector and made it go straight from the sensor to the VDO gauge.. Still no good.... I'm stumped.

THANKS AGAIN FELLERS FOR TAKING THE TIME TO HELP ME OUT. =D>

Wed Mar 23, 2011 2:49 pm

I have my VDO oil temperature sender in the oil drain plug location. In "winter" it takes a while of driving for it to register, gets to temperature much faster in AZ summer heat.

Does your fan shroud have operating thermostat flaps???

Wed Mar 23, 2011 2:55 pm

Cusser wrote: I have my VDO oil temperature sender in the oil drain plug location. In "winter" it takes a while of driving for it to register, gets to temperature much faster in AZ summer heat.

Does your fan shroud have operating thermostat flaps???

I know Arizona well, I went to AAI back in 1987 for the auto and diesel mechanic school... Very hot..

As for the fan shroud, negative, I don't have them. I've driven the car on city streets for about 30 minutes, on the freeway and the VDO gauge stays at 120.. I've stopped and checked the dip stick and it's cold to the touch.. What the??? :shock:

Wed Mar 23, 2011 3:45 pm

begood56vw wrote: Cusser wrote: I have my VDO oil temperature sender in the oil drain plug location. In "winter" it takes a while of driving for it to register, gets to temperature much faster in AZ summer heat.

Does your fan shroud have operating thermostat flaps???

I know Arizona well, I went to AAI back in 1987 for the auto and diesel mechanic school... Very hot..

As for the fan shroud, negative, I don't have them. I've driven the car on city streets for about 30 minutes, on the freeway and the VDO gauge stays at 120.. I've stopped and checked the dip stick and it's cold to the touch.. What the??? :shock:

To much apple juice in the oil sump.... If dip stick is cold so it goes....

Dale

Wed Mar 23, 2011 4:01 pm

ed_andersen wrote: I've got the recommended VDO Oil Temp, sender and "T" fitting from eGauge (used w/ a VDO pressure sender). Same problem. First sender was bad - no resistance change. VDO sent new one. Still no solution. I will check gauge as described in recent thread and get back. Ed

That is the worst possible location to mount a OT sender. Precious little oil moves past there. You need a better spot.

Wed Mar 23, 2011 5:05 pm

That is the worst possible location to mount a OT sender. Precious little oil moves past there. You need a better spot.[/quote]

As was asked earlier where would a good spot be?

Wed Mar 23, 2011 5:42 pm

My top two locations are the plug in front of the oil pickup tube bore in the case, and the oil filter adapter boss.

Wed Mar 23, 2011 6:06 pm

And you do have liquid Teflon on the threads and not teflon tape huh?? The filter adapter has to be grounded some way. And by the way I have mounted where yours is and it works fine.