Fuel and oil gauges pegging

[jim whelan]

Installed new gauges and circuit boards, pull harness and cleaned, repaired and inspected. Reinstalled with new tested ok gauges now fuel and oil peg( they move up slowly not instantly), temp nothing but shut off after a minute didn’t want to fry another set of gauges. No directional or flasher indicator lights either but I think separate issue. Where should I start short or Ivr ty Jim

 

[jim whelan]

It’s a 67 convertible fish

 

[Dana67Dart]

Is the IVR electronic or mehanical?

Iirc the Ivr is imbedded on your fuel gauge

I did not understand the temp gauge does it do the same?

Technically the gauge cluster is grounded by the screws that hold the dash to the car

But that would be a quick check. To see that you have 0 or near 0 ohms between the metal of the cluster and the car body

I am in the middle of the same thing. 67 dart. But in my case I know it is the OEM IVR. And am waiting on my RT-Engineering replacement to see how bad the temp / fuel gauge/s is/are fried.

 

[jim whelan]

Is the IVR electronic or mehanical?

Iirc the Ivr is imbedded on your fuel gauge

I did not understand the temp gauge does it do the same?

Technically the gauge cluster is grounded by the screws that hold the dash to the car

But that would be a quick check. To see that you have 0 or near 0 ohms between the metal of the cluster and the car body

I am in the middle of the same thing. 67 dart. But in my case I know it is the OEM IVR. And am waiting on my RT-Engineering replacement to see how bad the temp / fuel gauge/s is/are fried.

Oem fuel gauge, tested good temp didn’t move ice cold engine so I figured the sensor was not starting to ground yet I’m going to test that today

 

[Dana67Dart]

Oem fuel gauge, tested good temp didn’t move ice cold engine so I figured the sensor was not starting to ground yet I’m going to test that today

Typically the gauges have a no power position and will rise a tad with the key in the on position. As long as the senders are connected.

You can always VERY temperarilly touch the temp sender wire to ground and look for movement. (Safest with 2 people)

The reason I mentioned about the ground was that you said the turn signal indicators we're not working. They need the cluster groung to function as well.

If the IVR is mechanical you need ground for it to work or it feeds 12 V to the gauges

 

[jim whelan]

Typically the gauges have a no power position and will rise a tad with the key in the on position. As long as the senders are connected.

You can always VERY temperarilly touch the temp sender wire to ground and look for movement. (Safest with 2 people)

With key just in on position not running fuel and oil head to peg temp nothing will test the temp today ty if it was ivr in my fuel gauge was bad would all gauges still spike if I remove feed wire ty

 

[Dana67Dart]

if it was ivr in my fuel gauge was bad would all gauges still spike if I remove feed wire

Not sure I understand..

If you are saying if you remove the oil pressure sender wire and the fuel sender wire would that stop the gauges from pegging... Yes that should prevent them from pegging
Easy test too. Pull oil pressure sender wire from pressure sender, be sure it is not touching anything.

Do same for fuel sender, if gauges still move it would indicate a short in both wires some where along their path.

 

[jim whelan]

Not sure I understand..

If you are saying if you remove the oil pressure sender wire and the fuel sender wire would that stop the gauges from pegging... Yes that should prevent them from pegging
Easy test too. Pull oil pressure sender wire from pressure sender, be sure it is not touching anything.

Do same for fuel sender, if gauges still move it would indicate a short in both wires some where along their path.

 

[jim whelan]

Thank you I’m not good with electrical issues, but I guess I will get better will check grounds and do some tests. If I put a gauge between feed and at sensor to ground I should get the 5v if I get more the ivr is screwed correct

 

[Dana67Dart]

1. Measure resistance between back of instrument cluster and the body of the car and report back
2. Disconnect the fuel sender at the gas tank
3. Disconnect the temp sender at the intake
4. Disconnect the oil sender at the block
5. Turn key to "on" and report back what the gauges do.

Installed new gauges and circuit boards, pull harness and cleaned, repaired and inspected. Reinstalled with new tested ok gauges

1. Where did you get the "new" gauges from?
2. Did you compare the old cir board to the new cir board?
3. Did all the traces line up the same?
4. You state " Reinstalled with new tested ok gauges" how did you test the gauges?

 

[jim whelan]

1. Measure resistance between back of instrument cluster and the body of the car and report back
2. Disconnect the fuel sender at the gas tank
3. Disconnect the temp sender at the intake
4. Disconnect the oil sender at the block
5. Turn key to "on" and report back what the gauges do.

1. Where did you get the "new" gauges from?
2. Did you compare the old cir board to the new cir board?
3. Did all the traces line up the same?
4. You state " Reinstalled with new tested ok gauges" how did you test the gauges?

With an ohm test all around 22 and a 3 volt battery to all three gauges oil went half way fuel just past half and temp just past half trying to figure how to test ivr

 

[jim whelan]

With an ohm test all around 22 and a 3 volt battery to all three gauges oil went half way fuel just past half and temp just past half trying to figure how to test ivr

Ohms checked sender for oil and temp they were fine fuel still going straight to full on key turn so I pulled dash ohm check on ground for dash to ground was a little high thank you so much for the input

 

[Dana67Dart]

3 volts is about 1/2 the needed volts for the gauges

i'm not trying to be a dick but please answer each question. It is next to impossible to troubleshoot unless the eyes and ears answer the questions asked

 

[RedFish]

May seem a odd question but... did you remove the wires from the round harness connector? If yes, what diagram did you use to reinstall them? The drawing in the 67-factory service manual can be confusing. Its drawn rotated 90 degrees from how it oriented on the circuit board. At least two owners have put wires in wrong positions.

 

[jim whelan]

Ohms checked sender for oil and temp they were fine fuel still going straight to full on key turn so I pulled dash ohm check on ground for dash to ground was a little high thank you so much for the input

May seem a odd question but... did you remove the wires from the round harness connector? If yes, what diagram did you use to reinstall them? The drawing in the 67-factory service manual can be confusing. Its drawn rotated 90 degrees from how it oriented on the circuit board. At least two owners have put wires in wrong positions.

Yes looked over all wires and rang them out, nothing worked on dash before I started this work so I went back to square one. Could the fuel sending unit be stuck in the max position or even shorted or grounding strap missing going there next. I also think the flasher switch is shot might be why no indicator lights going to look for one of those. Do you know of any around ty

 

[Dana67Dart]

Yes looked over all wires and rang them out, nothing worked on dash before I started this work so I went back to square one. Could the fuel sending unit be stuck in the max position or even shorted or grounding strap missing going there next. I also think the flasher switch is shot might be why no indicator lights going to look for one of those. Do you know of any around ty

My friend you are shotgunning the problem.

Lets start over.

Problem statement - Your gauges peg when you turn on the key

lets find a path to a solution.

step one - If you disconnect all the sending wires from their respective senders does this still happen. (this will tell if there is a wiring issue) and report back

 

[jim whelan]

3 volts is about 1/2 the needed volts for the gauges

i'm not trying to be a dick but please answer each question. It is next to impossible to troubleshoot unless the eyes and ears answer the questions asked

I’m getting confused with in this format I thought I was reading and answering your thread and other got mixed in starting over going back to your questions.
1 ) 3 to 4 ohms
2) fuel sender not yet will do that today
3) done, no movement on gauge
4) done, no movement on gauge
5) got a set of gauges from a seller here gold member
6) yes right boards all traces lined up
7) ohm meter and 3v batteries

 

[jim whelan]

My friend you are shotgunning the problem.

Lets start over.

Problem statement - Your gauges peg when you turn on the key

lets find a path to a solution.

step one - If you disconnect all the sending wires from their respective senders does this still happen. (this will tell if there is a wiring issue) and report back

Ok going to work on grounding dash and reinstall then go follow your steps easy enough ty

 

[Dana67Dart]

I’m getting confused with in this format I thought I was reading and answering your thread and other got mixed in starting over going back to your questions.
1 ) 3 to 4 ohms
2) fuel sender not yet will do that today
3) done, no movement on gauge
4) done, no movement on gauge
5) got a set of gauges from a seller here gold member
6) yes right boards all traces lined up
7) ohm meter and 3v batteries

PERFECT!

1. 3-4ohms is a bit high but not life shattering. running a dedicated ground will eliminate that. report back after.
2. I suspect the same result as 3 and 4 ( fingers crossed)
3. if you disconnected the wire from the sender then you do not have a short in the sender wire wire
4. if you disconnected the wire from the sender then you do not have a short in the sender wire wire
   
5. did seller sell them as fully functional? and are they OEM or reproduction's? Gold member status is purchased, means nothing about the person selling stuff
6. Perfect!
7. the 3V battery will show that the gauge can move but does not show that the gauge is accurate.

AFTER you do some testing with the new ground if you still get the same issue I would pull the dash

I would suspect the IVR


The internal IVR can be tested, there are 3 posts on the back of the fuel gauge one, if you follow the trace is the 12V feed, one is the 5-6V pulsed DC output from the IVR that will also be common to one post on the Temp and fuel gauge. the 3rd post will go to the sender.

If you apply 12v to the 12v post and ground to the metal of the cluster and apply a 23 ohm resister between the sender post and ground (metal of the cluster) you should see a pulsed DC (an analog volt meter would be best) on the IVR post. if you see 12V steady for more than a second or 2 disconnect the 12V (that would indicate a bad IVR)

As seen from the back of the cluster

Internal IVR replacement instructions from RT-Eng
RTE Gauge Faq - rte

the red arrow pointing to the bend in the IVR arm is how RT-Eng says to disable the internal IVR

notice how long the 12 volts stays solid when the voltage is first applied. that is the heater coil heating up then the flashing is the bimetal making and braking the connection. the volt meter being digital has a hard time displaying anything because it is either 12V or 0 volts as the contact makes and breaks

In this video the lightbulb simulated the load of the gauges and the sender.

https://photos.app.goo.gl/h6j4eeww3SAhGiSn9

https://photos.app.goo.gl/2soBNRgGJUjE1F5fA

 

[jim whelan]

PERFECT!

1. 3-4ohms is a bit high but not life shattering. running a dedicated ground will eliminate that. report back after.
2. I suspect the same result as 3 and 4 ( fingers crossed)
3. if you disconnected the wire from the sender then you do not have a short in the sender wire wire
4. if you disconnected the wire from the sender then you do not have a short in the sender wire wire
   
5. did seller sell them as fully functional? and are they OEM or reproduction's? Gold member status is purchased, means nothing about the person selling stuff
6. Perfect!
7. the 3V battery will show that the gauge can move but does not show that the gauge is accurate.

AFTER you do some testing with the new ground if you still get the same issue I would pull the dash

I would suspect the IVR


The internal IVR can be tested, there are 3 posts on the back of the fuel gauge one, if you follow the trace is the 12V feed, one is the 5-6V pulsed DC output from the IVR that will also be common to one post on the Temp and fuel gauge. the 3rd post will go to the sender.

If you apply 12v to the 12v post and ground to the metal of the cluster and apply a 23 ohm resister between the sender post and ground (metal of the cluster) you should see a pulsed DC (an analog volt meter would be best) on the IVR post. if you see 12V steady for more than a second or 2 disconnect the 12V (that would indicate a bad IVR)

As seen from the back of the cluster
View attachment 1715838639


Internal IVR replacement instructions from RT-Eng
RTE Gauge Faq - rte

the red arrow pointing to the bend in the IVR arm is how RT-Eng says to disable the internal IVR

View attachment 1715838645

notice how long the 12 volts stays solid when the voltage is first applied. that is the heater coil heating up then the flashing is the bimetal making and braking the connection. the volt meter being digital has a hard time displaying anything because it is either 12V or 0 volts as the contact makes and breaks

In this video the lightbulb simulated the load of the gauges and the sender.

https://photos.app.goo.gl/h6j4eeww3SAhGiSn9

https://photos.app.goo.gl/2soBNRgGJUjE1F5fA

Ok it took a while but between snow and the cold I finally got dash back in, disconnected fuel sender no ground strap but that’s another issue. Started her up and oil and temp peg so I guess my new oem fuel gauge has a bad ivr. Fuel gauge didn’t move at all am I getting warmer thank

 

[Dana67Dart]

I would pull the dash at this point.

Get it on a bench and hook it up to a 12v source, car battery, 12V DC wall charger, etc.

Then do some checking.

The chassis of the cluster MUST be grounded to the negative of your supply.

Then you can check the IVR output on the back of the cluster. And do other propper testing of the guages.