Irratic temp readings
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Irratic temp readings
92 C4 135k miles, was out driving around yesterday with the outside temp around 80, I knew something was wrong when the temp gauge and digital kept jumping back/forth from 192 215....
as of right now just checked both tanks, recovery is where its spose to be and so is the black top tank, I don't get it, any suggestions??
as of right now just checked both tanks, recovery is where its spose to be and so is the black top tank, I don't get it, any suggestions??
Last edited by lectroglide; Apr 18, 2016 at 04:59 PM.
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Sounds more like a thermostat issue. Not fans since they come on at about 228 or so. Have you checked in front of radiator to be sure that all the debris is cleaned out?
How old is coolant?
How old is coolant?
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coolant is a yr old , will check for radiator blockage
Last edited by lectroglide; Apr 18, 2016 at 05:44 PM.
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My 94 has two bleeders but I just jack it up to make the cap the high point. You need to take the top shroud off and clean good. Might just be a plastic bag flopping around in there. They are big vacuum cleaners.
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just now getting under the car to see for blockage but have decided to have a complete flush done,.......... the car has green coolant should I stick with that or go to something else?? also am not sure what temp the thermostat is rated for so should their be a standard heat range it opens at?? thanx
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just got an estimate re coolant flush so I ask the guy if they did a complete flush Including the block he said they run fresh coolant thru the motor till its the fresh color but didn't mention anything about knock sensors, should I be concerned or just go with the flush? thanx guys!
Last edited by lectroglide; Apr 19, 2016 at 06:26 PM.
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Your '92 has two knock sensors in the bottom of the block. They should be removed for a complete flush.
The bottom of the block is a sump for sediments. Just draining coolant does not rid/clear the block of sediments.
Not only should the knock sensors be removed, but
water under pressure should be directed into the sensor holes to flush the block. Most shops will not do a complete flush, only drain the coolant.
It is suggested that the knock sensors be replaced with new, as they are probably the originals.
Your '92 has the LT1 engine, which is self-bleeding.
No need to be concerned with air in the system after refilling with new coolant.
The gyration of the temp gages may not be solved with a coolant flush, but it is a start.
The bottom of the block is a sump for sediments. Just draining coolant does not rid/clear the block of sediments.
Not only should the knock sensors be removed, but
water under pressure should be directed into the sensor holes to flush the block. Most shops will not do a complete flush, only drain the coolant.
It is suggested that the knock sensors be replaced with new, as they are probably the originals.
Your '92 has the LT1 engine, which is self-bleeding.
No need to be concerned with air in the system after refilling with new coolant.
The gyration of the temp gages may not be solved with a coolant flush, but it is a start.
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just got an estimate re coolant flush so I ask the guy if they did a complete flush Including the block he said they run fresh coolant thru the motor till its the fresh color but didn't mention anything about knock sensors, should I be concerned or just go with the flush? thanx guys!
Do not get your opti wet!!!!! I jack up the car to make the cap the high point and let the air bubble out my 94 has two bleeders not sure on yours.
Last edited by antfarmer2; Apr 19, 2016 at 07:50 PM.
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need to clarify something re the burping process, put the front end up on stands, run the motor for few min. then shut it off and it should get any air out , is that right???
and BTW am getting scepticle about a flush cuzz I just had it done last yr and have only put 5k miles on since, so gonna start with a new Tstat
and BTW am getting scepticle about a flush cuzz I just had it done last yr and have only put 5k miles on since, so gonna start with a new Tstat
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If you don't believe me, jack the vette into a vertical position, and stand on your head naked on the front lawn.
When the police arrive, urinate on their vehicle. Done.
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need to clarify something re the burping process, put the front end up on stands, run the motor for few min. then shut it off and it should get any air out , is that right???
and BTW am getting scepticle about a flush cuzz I just had it done last yr and have only put 5k miles on since, so gonna start with a new Tstat
and BTW am getting scepticle about a flush cuzz I just had it done last yr and have only put 5k miles on since, so gonna start with a new Tstat
I have the utmost respect for Seabright but disagree with the self bleed. It can still keep a air pocket by the thermostat that is why there are two brass bleeders.
Last edited by antfarmer2; Apr 20, 2016 at 09:42 PM.
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From: SANTA CRUZ CA
I've owned C4s for over 16 years. There are few, if any, C4 problems that haven't been discussed on this forum.
If you had taken the time to do a search on 'overheating', you might have found 500 threads that provided answers to your concern. Instead of suggesting that you perform a search, you were provided the courtesy of suggested solutions.
You decided that your 'overheating' problem was unique, so you started your own thread, eschewing
the numerous solutions others have provided the past 24 years.
If antfarmer wants to jack his vette to bleed the cooling system, so be it. That is an ignorant suggestion, but seems to be to your liking.
If you had taken the time to do a search on 'overheating', you might have found 500 threads that provided answers to your concern. Instead of suggesting that you perform a search, you were provided the courtesy of suggested solutions.
You decided that your 'overheating' problem was unique, so you started your own thread, eschewing
the numerous solutions others have provided the past 24 years.
If antfarmer wants to jack his vette to bleed the cooling system, so be it. That is an ignorant suggestion, but seems to be to your liking.
Last edited by don hall; Apr 20, 2016 at 10:59 PM.