Coolant temperature gauge issue

[bigjae46]

I have same exact issue, my coolant temp gauge is going crazy, it runs hot when in reality coolant temp is normal (Checked live data from OBD), it also stuck at middle when i remove key, next day gauge was bit lower than that and eventually it went to cold zone as it should but it still reads too high when i warm up the engine, i know it's cluster issue because when i converted my gauge from MPH to KMH using decal, i must have installed needles too far back because my fuel and speed gauge had exact same issue after i rebult and installed cluster, it was not returning to it's default position when i took key off, turned out needles were set too far back, i guess my temp gauge has same issue or i just have to recalibrate the temp gauge but thing is i don't know how that's done, if anyone knows how to do that i would appreciate a lot

You can disassemble the cluster and reclock or re-zero the coolant gauge by using your hand to move it to zero. I'd try that first. If it happens again then you'll need to either replace the cluster or replace the stepper motors/gears.

[Theraqa]

I have same exact issue, my coolant temp gauge is going crazy, it runs hot when in reality coolant temp is normal (Checked live data from OBD), it also stuck at middle when i remove key, next day gauge was bit lower than that and eventually it went to cold zone as it should but it still reads too high when i warm up the engine, i know it's cluster issue because when i converted my gauge from MPH to KMH using decal, i must have installed needles too far back because my fuel and speed gauge had exact same issue after i rebult and installed cluster, it was not returning to it's default position when i took key off, turned out needles were set too far back, i guess my temp gauge has same issue or i just have to recalibrate the temp gauge but thing is i don't know how that's done, if anyone knows how to do that i would appreciate a lot

[ZiMMie]

UPDATE: since many times the resolution to the problem is never updated by the OP, I took the car to a trusted forum member on here who has their own shop. They used this in dash menu system to check and reset the cluster. When checking it, it would go past the red into la la land, after reset it hits the end of red like it should. Gauge now points in the middle and issue is resolved as long as the cluster doesn't go haywire again. I can't remember the last exact test number as my memory isn't good. I appreciate y'all's help and hope this helps someone if they run across this in the future.

The temperature stepper motor was sticking.

It will happen again Mark my words!

either disassemble the cluster and change the stepper motor or start shopping for a used cluster.

So there was nothing wrong with your cluster/gauges is what your'e saying? Good news indeed thanks for updating us for future reference.

There was (still is) something wrong with the cluster. The stepper motor on the temp gauge is cannot return to it default stop position.

doing a cluster test will help but it will happen again in the future.

[jet_dogg]

So there was nothing wrong with your cluster/gauges is what your'e saying? Good news indeed thanks for updating us for future reference.

[Circa Surviven]

UPDATE: since many times the resolution to the problem is never updated by the OP, I took the car to a trusted forum member on here who has their own shop. They used this in dash menu system to check and reset the cluster. When checking it, it would go past the red into la la land, after reset it hits the end of red like it should. Gauge now points in the middle and issue is resolved as long as the cluster doesn't go haywire again. I can't remember the last exact test number as my memory isn't good. I appreciate y'all's help and hope this helps someone if they run across this in the future.

[Circa Surviven]

Just FYI OP, swapping in a new (used) cluster is a bit more than involved than just physically doing so. Your mileage will be off and the cluster will have the tamper dot until you sync the VIN and mileage.

Here's some resources on how to do that in case you wish to go the DIY route:
https://www.bimmerforums.com/forum/s...VIN-and-coding
https://forums.autolanka.com/topic/1...cement-coding/

Edit: wait, I just read through the post again (and looked at the pics) and the needle isn't all the way to left with the car completely off? You should really disassemble your cluster and make sure that the needle is physically aligned correctly before spending any money on anything else. The second link I posted is a good reference for how to disassemble and reassemble the cluster.

Yea with the car completely off it stays around the 1/4 marker or a little below. It just started happening one day.

yeah. A needle that's pushed too far onto it's peg can bind. Or maybe it just wasn't oriented on the peg correctly...

Was the cluster apart before this issue occured?

The cluster hasn't been touched. I guess this would be a good time to get some of the engine warming up lights replaced since some are burnt out.

[sapote]

Just FYI OP, swapping in a new (used) cluster is a bit more than involved than just physically doing so. Your mileage will be off and the cluster will have the tamper dot until you sync the VIN and mileage.

For some reasons I thought the temp gauge can be separated from the whole cluster; I own too many vintage cars.

[Obioban]

yeah. A needle that's pushed too far onto it's peg can bind. Or maybe it just wasn't oriented on the peg correctly...

Was the cluster apart before this issue occured?

[heinzboehmer]

Or buy a used one on eBay.

Just FYI OP, swapping in a new (used) cluster is a bit more than involved than just physically doing so. Your mileage will be off and the cluster will have the tamper dot until you sync the VIN and mileage.

Here's some resources on how to do that in case you wish to go the DIY route:
https://www.bimmerforums.com/forum/s...VIN-and-coding
https://forums.autolanka.com/topic/1...cement-coding/

Edit: wait, I just read through the post again (and looked at the pics) and the needle isn't all the way to left with the car completely off? You should really disassemble your cluster and make sure that the needle is physically aligned correctly before spending any money on anything else. The second link I posted is a good reference for how to disassemble and reassemble the cluster.

[sapote]

I had mine repaired by Circuit Board Medics and would recommend them. https://circuitboardmedics.com/1999-...luster-repair/

Or buy a used one on eBay.

[BMWE46M3]

I had mine repaired by Circuit Board Medics and would recommend them. https://circuitboardmedics.com/1999-...luster-repair/

[Circa Surviven]

The hidden displayed temp value and the gauge both use the sensing data from the sensor on the hard pipe under the intake, rear of the pump. From the pic showing the displayed 85F-ish while the gauge was over the middle. This means the sensor is OK but the gauge is out of calibration.

Thank you! I wasn't able to find a DIY on that sensor under the manifold. Usually with a DIY people will list symptoms of why they are in there replacing it.

[ZiMMie]

The hidden displayed temp value and the gauge both use the sensing data from the sensor on the hard pipe under the intake, rear of the pump. From the pic showing the displayed 85F-ish while the gauge was over the middle. This means the sensor is OK but the gauge is out of calibration.

That is Celsius.



The answer to this is all in the first post.

STOP CHASING GHOST!

FIX THE DAMN CLUSTER!

[sapote]

Is the gauge controlled by the temp sensor under the manifold or the lower radiator hose? I've read that a bad temp sensor would cause fueling issues because the computer will think the temperature is off. Does the car have an actual overheating message/light, or an ecu code that would pop up?

The hidden displayed temp value and the gauge both use the sensing data from the sensor on the hard pipe under the intake, rear of the pump. From the pic showing the displayed 85F-ish while the gauge was over the middle. This means the sensor is OK but the gauge is out of calibration.

[thegenius46m]

Get an infrared thermometer and confirm the radiator is consistent temps across the entire width. It may be clogged and time for a replacement OEM one. Did you bleed the cooling system properly to remove all the air? S54 is self bleeding but if you had a massive amount of air it may still be there.