Temp Gauge Adjustment
07-20-2017 | 11:18 AM
#1
Thread Starter
Intermediate
Joined: Dec 2013
Posts: 44
Likes: 0
From: Holland
Temp Gauge Adjustment
Hai there,
Is there a way to lower the temp gauge needle a bit ?
The needle comes in the red area then my twin fans begin to blow and the needle lowers again.
I would like to have that when the needle comes a bit over the last white line.
The mechanic told me the engine wasn't overheating. We changed the sensors for the gauge and for the fans. Also we put it a lower temp valve 80 degrees.
With a temp laser the egnine is perfectly fine, its just that the gauge needle is 1/4 to high in its reading.
Now i heard of putting in a inline resitor , but what sort , how many Ohms should that be.
thnx, and regards from Holland !!
Is there a way to lower the temp gauge needle a bit ?
The needle comes in the red area then my twin fans begin to blow and the needle lowers again.
I would like to have that when the needle comes a bit over the last white line.
The mechanic told me the engine wasn't overheating. We changed the sensors for the gauge and for the fans. Also we put it a lower temp valve 80 degrees.
With a temp laser the egnine is perfectly fine, its just that the gauge needle is 1/4 to high in its reading.
Now i heard of putting in a inline resitor , but what sort , how many Ohms should that be.
thnx, and regards from Holland !!
07-20-2017 | 01:52 PM
#3
Chronic Tool Dropper
Lifetime Rennlist
Member
Lifetime Rennlist
Member
Joined: Oct 2001
Posts: 20,506
Likes: 549
From: Bend, Oregon
RobbieStrosek, welcome to the group!
A good speedo/instrument shop should be able to remove and reposition needle if that's all that's wrong. In the US there are a couple prominent places that support the VDO and Porsche instruments. I'm sure there are similar services closer to where you are. The workshop manuals give the typical sensor resistance ranges at a couple different coolant temperatures, giving you some idea of where you might want to put the needle. Depending on the year of your car, your gauge may have temperature numbers at specific marks on the display, making it somewhat easier to get the needle back on correctly.
Housekeeping:
Please put the year of your car in every post. Different years have differences in lots of things, and my memory for who has what car isn't good enough anymore. Paid membership (<USD$20 a year) lets you build a signature area profile that can include your info in every post you make.
A good speedo/instrument shop should be able to remove and reposition needle if that's all that's wrong. In the US there are a couple prominent places that support the VDO and Porsche instruments. I'm sure there are similar services closer to where you are. The workshop manuals give the typical sensor resistance ranges at a couple different coolant temperatures, giving you some idea of where you might want to put the needle. Depending on the year of your car, your gauge may have temperature numbers at specific marks on the display, making it somewhat easier to get the needle back on correctly.
Housekeeping:
Please put the year of your car in every post. Different years have differences in lots of things, and my memory for who has what car isn't good enough anymore. Paid membership (<USD$20 a year) lets you build a signature area profile that can include your info in every post you make.
07-22-2017 | 08:22 AM
#4
Thread Starter
Intermediate
Joined: Dec 2013
Posts: 44
Likes: 0
From: Holland
well the light never came on, but the temp was always going in the red.
we replaced all the sensors and added a double elektr fan system.
placed a 80 degrees celcius valve instead of the 90 (factory). but still the needles go's into the red and then the fans kick in taking the needle back to somewhat for the red area.
as we did everything possible our only thought is that the gauge is not reading correctly.
same go's for the RPM gauge...driving 100km/h on 1000 rpm is a bit low hehe.
the 928 is from 1984.
we replaced all the sensors and added a double elektr fan system.
placed a 80 degrees celcius valve instead of the 90 (factory). but still the needles go's into the red and then the fans kick in taking the needle back to somewhat for the red area.
as we did everything possible our only thought is that the gauge is not reading correctly.
same go's for the RPM gauge...driving 100km/h on 1000 rpm is a bit low hehe.
the 928 is from 1984.
07-22-2017 | 08:28 PM
#7
Chronic Tool Dropper
Lifetime Rennlist
Member
Lifetime Rennlist
Member
Joined: Oct 2001
Posts: 20,506
Likes: 549
From: Bend, Oregon
Robbie --
There are some basics, like cleaning the ground connections where the instrument cluster ground near your throttle foot on the firewall. The WSM has a diagram with 3D coordinates for all the car's ground points. Annual cleaning of those will save you a lot of otherwise odd symptoms. In the case of the instrument readings, of course you'd look at things that are common to things in the gauge cluster.
The temperature sensor has two thermisters, one between each terminal on top and the engine ground. If you are measuring from pin to pin with an Ohm meter, you'll get a poor reading at best. Ground one meter lead on the engine away from the sensor, and take a reading from each of the two pins on the sender. They should be in range per WSM and current temperature. Move the engine-side lead to contact the sender shell directly and see if you get a different reading. Sometimes folks use sealing tape, or pain/powdercoating as part of a refinishing project will block the signal reference to the engine.
There are some basics, like cleaning the ground connections where the instrument cluster ground near your throttle foot on the firewall. The WSM has a diagram with 3D coordinates for all the car's ground points. Annual cleaning of those will save you a lot of otherwise odd symptoms. In the case of the instrument readings, of course you'd look at things that are common to things in the gauge cluster.
The temperature sensor has two thermisters, one between each terminal on top and the engine ground. If you are measuring from pin to pin with an Ohm meter, you'll get a poor reading at best. Ground one meter lead on the engine away from the sensor, and take a reading from each of the two pins on the sender. They should be in range per WSM and current temperature. Move the engine-side lead to contact the sender shell directly and see if you get a different reading. Sometimes folks use sealing tape, or pain/powdercoating as part of a refinishing project will block the signal reference to the engine.
Trending Topics
07-23-2017 | 12:11 PM
#8
Thread Starter
Intermediate
Joined: Dec 2013
Posts: 44
Likes: 0
From: Holland
Speedtoys, we tried some things and yes we tried that to.
Now when we drove for like 30 min. the needle comes into the red (still no warning light). But when i stopped the car and turned it of. the needle (with ignition on) comes to the white line in front of the red.
Once i start the engine again the needle goes straight into the red..
Maybe its a Voltage problem somewhere, car won't even start with doors open...and innerlights are on. Maybe the electric fans don't run at full speed as the alternator won't give enough power to run the car and fill the battery.
ill try to locate all the GND clusters and clean them, also the connector thats in the engine compartment near the radiator.
Now when we drove for like 30 min. the needle comes into the red (still no warning light). But when i stopped the car and turned it of. the needle (with ignition on) comes to the white line in front of the red.
Once i start the engine again the needle goes straight into the red..
Maybe its a Voltage problem somewhere, car won't even start with doors open...and innerlights are on. Maybe the electric fans don't run at full speed as the alternator won't give enough power to run the car and fill the battery.
ill try to locate all the GND clusters and clean them, also the connector thats in the engine compartment near the radiator.
