Author Topic: Coolant gauge lying? (Read 3765 times)

BrandC · « **on:** March 25, 2007, 11:26:30 PM »

I want to know if anyone else's coolant gauge misreads/misinforms the driver? I was on my 400 mile roadtrip and my coolant gauge read that it was overheating, exactly at the 3/4 mark. I pulled over and checked the engine bay. Obviously not overheating: coolant level was fine, no steam/smoke, and the engine was not unusually hot.

Does anyone else's coolant gauge lie to them? I'm wondering if I just need to replace/clean the two sensors in the cylinder head. TIA.

johna · « **Reply #1 on:** March 25, 2007, 11:33:44 PM »

Gauge should usually show around 1/2 way when at normal operating temperature.

3/4 is high but unless it is in the red it is not over heating, just higher than normal temperature. There probably won't be any steam or anything unless the coolant is boiling.

So are you sure your coiling system is operating ok? Fan clutch? Sticking closed thermostat? Blocked radiator? Radiator cap poor sealing? Hoses? No leaks, even minor ones?

That said, I have heard of gauge problems which could be bad connections, earths in the instrument cluster or the well-known leaking SI battery problem (unlikely on a 318is).

BrandC · « **Reply #2 on:** March 25, 2007, 11:56:38 PM »

John318isau: I'm thinking the same thing as far as grounds or bad connections.

I'm guessing because the car is older some of the connections might give a misreading in the gauge cluster, like inaccurate fuel level or coolant temperature.

My car is up to date as far as cooling items, probably moreso than the average 318is enthusiast. This is an intermittent problem, most of the time my needle reads accurately (a few clicks under 1/2).

Anyone else?

e9nine · « **Reply #3 on:** March 26, 2007, 06:48:29 AM »

Either a bad gauge or bad cluster.

When you tap the cluster, does the needle "dance." I have had the same issue and once identified as a needle/cluster issue. I make sure to only get "worried" when it parks itself in the red.

Best remedy is a used cluster, cheapest fix; pull the cluster out and tighten the ground/earth nut if you see it. If you don't see it (you'll be surprised how many e30 fuel and temp gauges have lost their nuts [haha]) that's the cause of your issue as well.

gearheadE30 · « **Reply #4 on:** March 26, 2007, 03:12:20 PM »

huh, my car has this problem as well and didn't bother looking for it. thanks for the info, now I have something to do

BrandC · « **Reply #5 on:** March 26, 2007, 06:24:11 PM »

Quote from: e9nine;22223

When you tap the cluster, does the needle "dance." I have had the same issue and once identified as a needle/cluster issue. I make sure to only get "worried" when it parks itself in the red.

Sure does "Dance" when I hit the dashboard hard enough. I will try tightening behind the cluster. Thanks dude!

mooninite · « **Reply #6 on:** March 26, 2007, 06:29:47 PM »

i have this problem with both my fuel and temp gauge. if i tap my temp gauge it does "dance" but with the fuel gauge i tap it and it goes to its normal level, usually. some times i dont know im on empty because my gauge reads full but my reserve light comes on. how should i go about fixing these problems?
(sorry if this was allready posted but i sort of got confused)

Choking Hazard · « **Reply #7 on:** March 26, 2007, 10:07:26 PM »

Look on bimmerDIY
http://www.bimmerdiy.com/e30/electrical

ScreamerBeemer · « **Reply #8 on:** March 28, 2007, 10:56:37 AM »

My temp guage reads low, centered between normal and cold is normal on this car. Probably had something to do with the time I dropped the cluster on the floorboard when I was trying to put it back in the dash.

Shocker · « **Reply #9 on:** March 28, 2007, 04:48:55 PM »

My temp gauge only gets to 1/4 and I have tired two different temp gauges and bought a new temp senders. I think it�s the instrument cluster board, but I�m to lazy to take it apart again.