wlkelley3 Dork
May 20, 2012 8:46 p.m.

Got a question for smarter than me people. Still learning all these sensors and electronics on these newer cars. Car in question - 2004 RX8, no mods, engine replace a couple years ago under warranty at 98,000, now at 123,000 so roughly 25,000 on engine. Coolant level sensor light comes on once in a while, usually after semi-hard cornering and sometimes after hard acceleration with RPM above 4,000. Goes off after a minute or two and recently learned a trick to turn it off quicker, depress the clutch and let the RPM drop to idle and light goes off. I check the coolant level and its alway right where it's supposed to be. At first thought it was the coolant level sensor but now I'm not so sure that the water pump isn't involved in this malady somehow. Dropping RPMs to turn off the light is what makes me think this. It doesn't overheat, in fact the temp is below halfway on the gage and stays there. No fluctuation. Is annoying and would like to fix it but not sure what to fix. What say ye of more knowledge than me?

JtspellS HalfDork
May 20, 2012 9:18 p.m.

Don't trust the stock temp gauge because it does not move until somewhere around 210 and by then its too late, find something that can tell you your actual coolant temp then go from there.

MrJoshua PowerDork
May 20, 2012 9:20 p.m.

Sounds like air in the system to me.

amg_rx7 Dork
May 20, 2012 10:44 p.m.
MrJoshua wrote: Sounds like air in the system to me.

Me too.

any coolant leaks? Do a coolant system pressure test and double check. You could have a worn hose that is leaking when pressurized or a tired hose clamp that is allowing air to enter the system during cool down.

wlkelley3 Dork
May 21, 2012 11:53 a.m.

I thought of that and will look into it but haven't touched the coolant system and it doesn't loose coolant. No coolant leaks. Its only been the last couple months it started and getting more often.

Snrub New Reader
May 21, 2012 3:05 p.m.

I've been having a similar issue for ~8 months, no apparent loss of coolant. Apparently there can be issues with the coolant level sensor. Logically this sensor is integrated into the overflow tank which would necessitate a whole new tank assembly. :)

iceracer UltraDork
May 21, 2012 5:54 p.m.

In most cases the coolant light has nothing to do with flow, just the level in the tank. Now if it is an overheat warning light, different story.

wlkelley3 Dork
May 21, 2012 7:44 p.m.

@ Snrub. That figures. Couldn't be a cheap fix, after all it is an RX8 with $25 each spark plugs. Have to get the complete tank.

@ iceracer. Yeah your right but its annoying.

JtspellS HalfDork
May 21, 2012 8:21 p.m.

$125 from mazmart


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