E30 coolant temp question??

[NeedaE30]

OK so, Since I purchased the car about a year ago, the coolant temp gauge has never reached 12 oclock or the middle mark. It is consistently at about 1/4 or between 1/4 and 1/2. I thought this would make the ecu think I'm running cold and make it run rich, the exhaust is sometimes stinky with fuel smell (though this could be another issues all together)

I've replaced everything in the cooling system except the friggin heater core

i've done the following
waterpump
thermostat
radiator
fan clutch
both coolant temp sensors/senders on the thermostat housing
all coolant hoses
new coolant
the heat blows... extremely hot

Is this a gauge cluster issue? My tach and mpg gauges just recently stopped working, 10 minutes after i was driving the car. If the gauge cluster is in fact athe culprit, and the temp gauge is reading cold, even though the engine is actually nice an hot, will the gauge cluster send that signal to the ecu and make the m20 run rich?

guess i should look at the gauge cluster since everything in the cooling system has been done...

any other idears?

[raudonis]

There are two different separate temp sensors - 1 for the cluster and other 1 for the ECU. Most likely SI-batteries inside the cluster have died.

[Sea Aych]

There are two different separate temp sensors - 1 for the cluster and other 1 for the ECU. Most likely SI-batteries inside the cluster have died.

Yup - brown top one is the gauge sender (only one wire, if you pop the connector off), and the blue one is the one for the ECU (two wires). The gauge in the cluster has nothing to do with sending the temp information to the ECU.

That being said, don't worry about the gauge running between 1/4 and 1/2 - it's only a couple degrees difference anyways, and mine sits there all the time too (a bit closer to the 1/2). If yours is near the 1/4 though, yeah, there may be another issue. Does it bounce around, or is it steady? For the running rich, have you changed the O2 sensor? Also, SI board batteries.

[NeedaE30]

I replaced both of the coolant temp sensors, i just got done driving for about 45 minutes and the coolant temp gauge just barely got above the 1/4 mark... and stays extremely steady and does not fluctuate,

the si board batteries arent fried and i now know why my tach doesnt work but , the tach problem was recent and the coolant gauge has acted this way for over a year..

like i said everything in the cooling system is new except the heater core

I havent replaced the O2 sensor, and that is on the list, i also have no working check engine light. it doesnt come on when the ignition is turned on or started.. i checked for a blown bulb and the bulb is working properly check for power in the wires no power coming out of the wires. so i cant do any stomp test or even see if i have any codes at all. any idears?

[jlevie]

What thermostat is in the car? The stock 80C thermostat would have the needle right about half way between the 1/4 & 1/2 marks. A 70C unit would have the needle just above the 1/4 mark.

[nando]

Get an 80c thermostat.

[NeedaE30]

well then i guess that should probably be the problem? i believe i did purchase the cooler thermostat of the bunch

[digger]

OK so, Since I purchased the car about a year ago, the coolant temp gauge has never reached 12 oclock or the middle mark. It is consistently at about 1/4 or between 1/4 and 1/2. I thought this would make the ecu think I'm running cold and make it run rich, the exhaust is sometimes stinky with fuel smell (though this could be another issues all together)

I've replaced everything in the cooling system except the friggin heater core

i've done the following
waterpump
thermostat
radiator
fan clutch
both coolant temp sensors/senders on the thermostat housing
all coolant hoses
new coolant
the heat blows... extremely hot

Is this a gauge cluster issue? My tach and mpg gauges just recently stopped working, 10 minutes after i was driving the car. If the gauge cluster is in fact athe culprit, and the temp gauge is reading cold, even though the engine is actually nice an hot, will the gauge cluster send that signal to the ecu and make the m20 run rich?

guess i should look at the gauge cluster since everything in the cooling system has been done...

any other idears?

if you are calling the 1/4 mark the tick half way between edge of blue and 12oclock then you are on a wild goose chase

i have a 70C tstat and a digital readout on my laptop anywhere between the two ticks is ok the dash gauge aint that accurate