Coolant Temperature - Do I have a problem?
Thread Starter
5th Gear
Joined: Jul 2001
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From: Sarnia Ontario
Coolant Temperature - Do I have a problem?
Last week I noticed that there was a large discrepancy between my Engine Coolant Temperature Gauge and my numeric gauge (LCD) (I have a ?95 LT1). The temperature on the Gauge was almost in the shaded area (~240°F) while the LCD display indicated a coolant temperature of only 214°F. Should there be a difference between these two indications? Note: it was a very warm day out and I was stuck in stop and go traffic ? windows open, A/C off.
I have also noticed that my cooling fans don?t seem to come on to often. I know they are on when the A/C is on, but I have not seen them come on at any other time. At what coolant temperature should they come on at and what is the best way to diagnose if I have a problem with this system?
Thanks,
Rob J.
:confused:
I have also noticed that my cooling fans don?t seem to come on to often. I know they are on when the A/C is on, but I have not seen them come on at any other time. At what coolant temperature should they come on at and what is the best way to diagnose if I have a problem with this system?
Thanks,
Rob J.
:confused:
Team Owner
Joined: Apr 2001
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From: Dallas TX
Re: Coolant Temperature - Do I have a problem? (RJanzen95)
My dig and analog gauges are off a bit too, but there is a valid reason. The temperatures are from different parts of the engine.
The analog is coming from a temp sensor on the passenger side cyl. head. The digital is coming from the temp sensor mounted in the water pump.
Naturally, the water is going to be a little lower temperature than the head because the water is soaking up the heat from the head. If you see your analog guage temps climb to the 260 mark, i would seriously pull over and let it cool... that or roll (button) down the windows and crank up the heater. I had to do this a couple times when my waterpump was going out... only way to keep my dig. temp to stay below 240* in very bad traffic at 5pm. If you run very long at 260+, you risk serious head damage (ie warping) and you can kiss the seals in your engine good-bye.
[Modified by Glock'94, 3:55 PM 8/7/2001]
The analog is coming from a temp sensor on the passenger side cyl. head. The digital is coming from the temp sensor mounted in the water pump.
Naturally, the water is going to be a little lower temperature than the head because the water is soaking up the heat from the head. If you see your analog guage temps climb to the 260 mark, i would seriously pull over and let it cool... that or roll (button) down the windows and crank up the heater. I had to do this a couple times when my waterpump was going out... only way to keep my dig. temp to stay below 240* in very bad traffic at 5pm. If you run very long at 260+, you risk serious head damage (ie warping) and you can kiss the seals in your engine good-bye.
[Modified by Glock'94, 3:55 PM 8/7/2001]
Instructor
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Re: Coolant Temperature - Do I have a problem? (RJanzen95)
mine ran hot until I cleaned out the front of the radiator. Over half was clogged with debris or bent fins. It should be a yearly maintainance thing. When was yours last done?
Team Owner
Joined: Apr 2001
Posts: 22,267
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From: Dallas TX
Re: Coolant Temperature - Do I have a problem? (LouisBarton)
I haven't had time to do that yet... :(. I've been too busy replacing my optispark and waterpump and wires and coil and... well.. you get the point. This is the next thing I'm going to work on. I can see some fins that are bent and need some straightening.
Melting Slicks
Joined: Feb 1999
Posts: 3,261
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From: sonoma ca
Re: Coolant Temperature - Do I have a problem? (RJanzen95)
RJanzen95,
Your fans operate in concert & will come on at
226F, low speed, & off at 221F. Your fans will come on at 235F, high speed & off at 230F.....then to lo speed. There is an access area on the right side of the radiator shroud when you can check the front of the radiator for junk, etc. My 95 will run at 205F
when stopped, in traffic, 95 degree day, with the a/c on.
Your fans operate in concert & will come on at
226F, low speed, & off at 221F. Your fans will come on at 235F, high speed & off at 230F.....then to lo speed. There is an access area on the right side of the radiator shroud when you can check the front of the radiator for junk, etc. My 95 will run at 205F
when stopped, in traffic, 95 degree day, with the a/c on.
Team Owner
Joined: Apr 2001
Posts: 22,267
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From: Dallas TX
Re: Coolant Temperature - Do I have a problem? (RJanzen95)
Oh, and to answer your other questions... the main fan should come on at 228* F (the one on the driver's side) and the other fan should come on the second you turn on the A/C (passenger side). I believe if the engine temp gets to 235 or something around that, the A/C fan will turn on automatically as well.
The 228* reading from above comes from the ECT sensor (aka the digital temp sensor). The analog controls the 235 or something comes from the analog gauge (i believe)
[Modified by Glock'94, 4:31 PM 8/7/2001]
The 228* reading from above comes from the ECT sensor (aka the digital temp sensor). The analog controls the 235 or something comes from the analog gauge (i believe)
[Modified by Glock'94, 4:31 PM 8/7/2001]
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Instructor
Joined: Feb 2001
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From: Raleigh North Carolina
Re: Coolant Temperature - Do I have a problem? (RJanzen95)
I have a '93. The anaolog guage will get up to 240 within a couple of minutes in stop and go traffic. The digital will get up to 228 before the fan comes on. If I let the digital get up high enought to turn the fans on, the analog guage is almost to 260. What I do in stop and go traffic is turn the a/c on, this turns the fans on and keeps the digital at about 205-210, and the analog at about 220, that was today in 97 degree stop and go traffic. I clean my radiator once a month, there's a lot of stuff in there after only a month. I need to do the mod for the fan control switch, that would really help out. That's just a switch mounted somewhere in the car you can switch on to turn the fans on when you want them on.. Some people go with a different chip that turns the fans on at a lower temp, along with a 180 degree thermostat. So far switching the a/c has kept everything cool, including me...
jimi lane
jimi lane
Drifting
Joined: Nov 1999
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From: Yorktown Heights NY
Re: Coolant Temperature - Do I have a problem? (RJanzen95)
Pull your radiator!
Use a good spray-on wash-off detergent wheel cleaner with a soft bristle brush (only with the direction of the fins) and let things sit and soak for about 10 minutes. Rinse with hose spray in direction opposite normal air flow....you'll be surprised at all the crap and grime that comes out :crazy:
If you really want to get it to cool like it just stepped of the line at Bowling Green, spend about 10 hours like I did with tweezers cleaning all the little pebbles, bug carcases and other assorted goodies from between those closely spaced delicate aluminum radiator fins ;)
I also run with two quarts of Purple Ice mixed in my Dexcool (even though I have a 95) :yesnod:
Today it topped 101F on the East River Drive in Manhattan, and with full A/C in stop-and-go traffic I only topped out at 215F.....this would have roasted me before I completed did this maintanence project:D
[Modified by 95BLKVette, 11:35 PM 8/7/2001]
Use a good spray-on wash-off detergent wheel cleaner with a soft bristle brush (only with the direction of the fins) and let things sit and soak for about 10 minutes. Rinse with hose spray in direction opposite normal air flow....you'll be surprised at all the crap and grime that comes out :crazy:
If you really want to get it to cool like it just stepped of the line at Bowling Green, spend about 10 hours like I did with tweezers cleaning all the little pebbles, bug carcases and other assorted goodies from between those closely spaced delicate aluminum radiator fins ;)
I also run with two quarts of Purple Ice mixed in my Dexcool (even though I have a 95) :yesnod:
Today it topped 101F on the East River Drive in Manhattan, and with full A/C in stop-and-go traffic I only topped out at 215F.....this would have roasted me before I completed did this maintanence project:D
[Modified by 95BLKVette, 11:35 PM 8/7/2001]
Drifting
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From: the passing lane, SO MOVE IT!!!!
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St. Jude Donor '06
Re: Coolant Temperature - Do I have a problem? (RJanzen95)
I had a similar problem, and it is now fixed. Check out this thread http://www.corvetteforum.cc:88/zerothread?id=93612
Best fix, and it was free.
Best fix, and it was free.
Team Owner
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Re: Coolant Temperature - Do I have a problem? (365dayLT1)
my guages are off too, but you definitely shouldnt be runnin that hot
Racer
Joined: Jul 2000
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From: Frisco, Texas USA
Re: Coolant Temperature - Do I have a problem? (RJanzen95)
I had the same problem recently with disasterous results. I recently replace the waterpump without replacing the coupling that connects the waterpump to the spline on the camshaft. The result was the sensor on the waterpump read about 225 while the sensor on the block went over 260. The sensor on the waterpump also triggers the warning ligt in the DIC so no engine temperature warning was issued. The result was an overheated engine and a tow home. I still haven't accessed the extent of the damage. The moral of the story here is if there is a discrepancy between the digital readout and the analog one don't operate you car until you get to the bottom of the problem and check your waterpump if there is a discrepancy between the two gauge readings.
Safety Car
Joined: Mar 2000
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From: Hillsboro OR
Re: Coolant Temperature - Do I have a problem? (RJanzen95)
Do a comparison between your digital oil temp, digital water temp, outside air temp when the car is cold. They should be within a few degrees of each other. Compare the digital water temp and digital oil temp when the car starts running hot. If the oil temp is closer to the analog gauge than the digital temp gauge, you could have a bad ECT or some other problem.
Instructor
Joined: Aug 2001
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Re: Coolant Temperature - Do I have a problem? (AquaMetallic94LT1)
My friend in his 95 has been running hotter than usual lately. He just had a flush and fill done at the dealership. They didn't top off his coolant system enough. After he heated his car up I told him to check his overflow tank. It was empty. This is very bad. He had to refill his overflow tank with about half a container of coolant, 2 or 3 quarts I think. Since then he has been running alot cooler(just like my car 194-200, up to 208 in traffic w/ac on in the great east coast heat wave w/high temps around 100, both 95's have stock cooling systems). Check this first. It's the cheapest and the easiest check to do before you go getting really involved. Preventative Maintenance is the cheapest and best way to avoid spending lots of money. Owner's manuals have the recommended intervals to check fluids and such on your car. You can't remember everything, I hope this helps you out.
Le Mans Master
Joined: Apr 2000
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From: Manassas VA
Re: Coolant Temperature - Do I have a problem? (95CYC4)
A long time ago, someone posted that it says in the owners manual the analog gage is for a point of reference. The temp check should be done by the digital guage. Mine reads way low, compared to the digital.
Thread Starter
5th Gear
Joined: Jul 2001
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From: Sarnia Ontario
Re: Coolant Temperature - Do I have a problem? (RJanzen95)
Thanks Everybody,
I did a coolant flush of the system and took the radiator out for a cleaning. What a mess inside. Not a bad job, except my driveway/garage is not air-conditioned. Just finished taking it out for a little spin ? with the temperature today of 93°F (humidex of 107°F) ? the engine digital temp ran at 197°F, while the analog was approximately 212°F (A/C on).
Question - with all the crude that makes its way into the rad - has anyone experimented with putting some sort of messing on the air inflow.
Thanks!
I did a coolant flush of the system and took the radiator out for a cleaning. What a mess inside. Not a bad job, except my driveway/garage is not air-conditioned. Just finished taking it out for a little spin ? with the temperature today of 93°F (humidex of 107°F) ? the engine digital temp ran at 197°F, while the analog was approximately 212°F (A/C on).
Question - with all the crude that makes its way into the rad - has anyone experimented with putting some sort of messing on the air inflow.
Thanks!
Instructor
Joined: Aug 2001
Posts: 231
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Re: Coolant Temperature - Do I have a problem? (RJanzen95)
I tend to try and stay clear of cows and deer on the way to work, they can really clog up your radiator....lol
I haven't tried putting a screen or anything to protect my radiator. Just keep an eye on it. I am happy to see that you did the simplest, but messiest job, coolant flush on your car. Just make sure that your overflow tank is at the correct level. It doesn't take much to make these cars run cool, even in the high temps. Enjoy your car.
I haven't tried putting a screen or anything to protect my radiator. Just keep an eye on it. I am happy to see that you did the simplest, but messiest job, coolant flush on your car. Just make sure that your overflow tank is at the correct level. It doesn't take much to make these cars run cool, even in the high temps. Enjoy your car.
Le Mans Master
Joined: Jul 2000
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From: Cincinnati, OH
Re: Coolant Temperature - Do I have a problem? (Glock'94)
:lol: :lol: :yesnod: :crazy: :smash: :cool: :jester :conehead :clown :hat :p: :chevy ;) :cheers: :cheers: :cheers: