phantom low coolant
Team Owner
Joined: Feb 1999
Posts: 37,190
Likes: 20
From: Trying to get back to Bokeelia, FLA-USA
St. Jude Donor '04-'05-'06, '15
Re: phantom low coolant (markmaz)
FWIW...my 94 Lumina did the same thing...depending on the year....if yours uses that square gray sensor like the Lumina...its probably bad...
Le Mans Master
Joined: Dec 1999
Posts: 8,540
Likes: 1
From: And on the fifth day, subpoenas were served to Obama senior staff
Re: phantom low coolant (markmaz)
I thought the same on my 89, but it turns out it was real.
You need to "pack" the system. Make up a mix of AF and clean water (50/50 or so). On a cold engine remove the radiator cap and start engine, turn heater on full hot (fan level does not really matter). When it begins to warm up - the thermostat will open and coolant level will drop. Top up level. Then wait for it to open again and have someone hold throttle around 1500 rpm. Level will drop - top up level. Have cap ready to install and install when level starts to overflow.
If level drops again after a week or so, then look for bad radiator cap (or poor seal to radiator), bad connections to overflow tank, leak in overflow tank or leaks in the cooling system. I'm almost two years now with no low coolant light on orginal sensor.
Good Luck,
Pete
You need to "pack" the system. Make up a mix of AF and clean water (50/50 or so). On a cold engine remove the radiator cap and start engine, turn heater on full hot (fan level does not really matter). When it begins to warm up - the thermostat will open and coolant level will drop. Top up level. Then wait for it to open again and have someone hold throttle around 1500 rpm. Level will drop - top up level. Have cap ready to install and install when level starts to overflow.
If level drops again after a week or so, then look for bad radiator cap (or poor seal to radiator), bad connections to overflow tank, leak in overflow tank or leaks in the cooling system. I'm almost two years now with no low coolant light on orginal sensor.
Good Luck,
Pete
Safety Car
Joined: Jun 2001
Posts: 4,397
Likes: 336
From: Haymarket VA
Re: phantom low coolant (PeteL)
I thought the same on my 89, but it turns out it was real.
You need to "pack" the system. Make up a mix of AF and clean water (50/50 or so). On a cold engine remove the radiator cap and start engine, turn heater on full hot (fan level does not really matter). When it begins to warm up - the thermostat will open and coolant level will drop. Top up level. Then wait for it to open again and have someone hold throttle around 1500 rpm. Level will drop - top up level. Have cap ready to install and install when level starts to overflow.
If level drops again after a week or so, then look for bad radiator cap (or poor seal to radiator), bad connections to overflow tank, leak in overflow tank or leaks in the cooling system. I'm almost two years now with no low coolant light on orginal sensor.
Good Luck,
Pete
You need to "pack" the system. Make up a mix of AF and clean water (50/50 or so). On a cold engine remove the radiator cap and start engine, turn heater on full hot (fan level does not really matter). When it begins to warm up - the thermostat will open and coolant level will drop. Top up level. Then wait for it to open again and have someone hold throttle around 1500 rpm. Level will drop - top up level. Have cap ready to install and install when level starts to overflow.
If level drops again after a week or so, then look for bad radiator cap (or poor seal to radiator), bad connections to overflow tank, leak in overflow tank or leaks in the cooling system. I'm almost two years now with no low coolant light on orginal sensor.
Good Luck,
Pete
ditto, exact same results
Team Owner
Joined: Mar 2001
Posts: 30,861
Likes: 293
From: Boston, Dallas, Detroit, SoCal, back to Boston MA
Re: phantom low coolant (markmaz)
If you've got an LT1 don't forget to burp it.
There's a bleeder screw on top of the thermostat housing, under the throttle body. ( watch the opti! :eek: )
There's a bleeder screw on top of the thermostat housing, under the throttle body. ( watch the opti! :eek: )
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Racer
Joined: Nov 2000
Posts: 440
Likes: 0
From: Corvallis OR
Re: phantom low coolant (markmaz)
What i did was the throttle body pybass mod. Also drilled two tiny holes in the thermostat. Then in the bypass hose, i put one of those radiator flush fittings on the topmost area. Its higher then any other part of the cooling system. Then i just pour coolant in that to top off and get rid of the air pockets.
Jim-K
Jim-K
