Overheating?

02Blazer · 07-24-2009, 01:43 AM

Hey guys, I have a kind of odd overheating issue occurring with my blaze. When I got home today I noticed my "check gauges" lamp was on, and the temp gauge was pegged. I immediately popped the hood to see what carnage had taken place. Nothing. The engine didn’t even smell hot, nor was it driving adversely. When I started the truck right after to make sure the fan was spinning the idle was a bit high for a moment then it came back down.
I went to leave about 45 minutes later for a quick 2 mile drive, within 5 minutes of starting the vehicle the gauge was pegged again. When I got out I popped the hood again to check things out. Again, nothing looked out of the norm, no burning coolant smell, no bubbling, no smoke, and she was running fine. The truck is a 2002, 4.3 with a manual, just over 56,000 miles, basically stock and I’ve never had any cooling issues. Temperature would always be at just below mid (210 if my mem serves correct).
I searched for a while and couldn’t find anything similar. Anyone experienced anything like this or have any idea as of the cause? My oil is crystal clear, changed 3000 miles ago, so I don’t think anything serious has happened to the motor. Has the sender gone bad perhaps? If it has, is there a way I can test it with a multimeter? Thermostat gone bad? I appreciate any suggestions and information you guys can provide. Thank you.

Rhotpursuit · 07-24-2009, 10:00 AM

Hate to state the obvious but damn...did you check the coolant level???

bigb19812000 · 07-24-2009, 10:56 AM

my 2000 s10 had a similar issue and it turned out the heater hoses were clogged up with what looked like some kind of stopleak or something.So reach back to heater hoses and squeeze them if you here a crunching sound that is your problem.Also check your t-stat they go out all at one time sometimes .YOu can also look at the weep hole at the bottom of your water pump maybe it is on its way out

***DJDAudio*** · 07-24-2009, 11:01 AM

do you get heat out of the vents?

When my waterpump went bad this happened It was overheating and nothing was hot! lol

02Blazer · 07-24-2009, 11:30 AM

Thanks for the suggestions guys. There was nothing coming out of the weep hole on the pump, nothing dripping under the vehicle whatsoever. My SES light is not on. My coolant level is good, radiator is full. I'll have to check the heater lines later, I backflushed the whole system about 10,000 miles ago, so i dont think it would be an issue, but you never know...
Is there a way to see if the sender is bad via resistance check with a multimeter? If so, what are the parameters of the test? Also with the thermostat, can i test that on the truck? I remember boiling the t-stat on my chevelle back in the day to see whether it was opening, just wanted to know if anyone had a different approach. Thanks all.

bigb19812000 · 07-24-2009, 11:45 AM

Quote: Originally Posted by 02Blazer

Thanks for the suggestions guys. There was nothing coming out of the weep hole on the pump, nothing dripping under the vehicle whatsoever. My SES light is not on. My coolant level is good, radiator is full. I'll have to check the heater lines later, I backflushed the whole system about 10,000 miles ago, so i dont think it would be an issue, but you never know...
Is there a way to see if the sender is bad via resistance check with a multimeter? If so, what are the parameters of the test? Also with the thermostat, can i test that on the truck? I remember boiling the t-stat on my chevelle back in the day to see whether it was opening, just wanted to know if anyone had a different approach. Thanks all.

Take the t-stat out put the truck back together without the t-stat .Run it.if it gets hot it was not your t-stat .

Rhotpursuit · 07-24-2009, 08:45 PM

Quote: Originally Posted by bigb19812000

my 2000 s10 had a similar issue and it turned out the heater hoses were clogged up with what looked like some kind of stopleak or something.So reach back to heater hoses and squeeze them if you here a crunching sound that is your problem.Also check your t-stat they go out all at one time sometimes .YOu can also look at the weep hole at the bottom of your water pump maybe it is on its way out

A clogged heater core will not cause it to overheat.

bigb19812000 · 07-24-2009, 09:08 PM

Quote: Originally Posted by Rhotpursuit

A clogged heater core will not cause it to overheat.

a clogged up any thing in the cooling system will cause it to overheat by restricting proper flow of coolant.so if your heater lines are clogged and still hooked up it will most likely overheat

02Blazer · 07-25-2009, 03:13 AM

So I got a chance to work on her tonight and me and pops figured we'd start small and move our way up. Swapped the thermostat out, fired her up and let her sit for a while, the gauge never moved past halfway, the t-stat did the trick. I’m stoked. Thanks for taking the time to help me out everyone, later!!

bigb19812000 · 07-25-2009, 10:16 AM

Quote: Originally Posted by 02Blazer

So I got a chance to work on her tonight and me and pops figured we'd start small and move our way up. Swapped the thermostat out, fired her up and let her sit for a while, the gauge never moved past halfway, the t-stat did the trick. I’m stoked. Thanks for taking the time to help me out everyone, later!!

glad it all worked out for you.Not to make you worry or nothing but soon after my t-stat replacement it was time for a water pump.SO keep an eye on taht temp and coolant level.

07-24-2009, 01:43 AM	#1
02Blazer Registered User Age: 31 Join Date: Jul 2006 Posts: 17 Location: Playa Del Rey, CA User is: OffLine	Overheating? Hey guys, I have a kind of odd overheating issue occurring with my blaze. When I got home today I noticed my "check gauges" lamp was on, and the temp gauge was pegged. I immediately popped the hood to see what carnage had taken place. Nothing. The engine didn’t even smell hot, nor was it driving adversely. When I started the truck right after to make sure the fan was spinning the idle was a bit high for a moment then it came back down. I went to leave about 45 minutes later for a quick 2 mile drive, within 5 minutes of starting the vehicle the gauge was pegged again. When I got out I popped the hood again to check things out. Again, nothing looked out of the norm, no burning coolant smell, no bubbling, no smoke, and she was running fine. The truck is a 2002, 4.3 with a manual, just over 56,000 miles, basically stock and I’ve never had any cooling issues. Temperature would always be at just below mid (210 if my mem serves correct). I searched for a while and couldn’t find anything similar. Anyone experienced anything like this or have any idea as of the cause? My oil is crystal clear, changed 3000 miles ago, so I don’t think anything serious has happened to the motor. Has the sender gone bad perhaps? If it has, is there a way I can test it with a multimeter? Thermostat gone bad? I appreciate any suggestions and information you guys can provide. Thank you.
	[Reply w/Quote]

07-24-2009, 10:00 AM	#2
Rhotpursuit Ticket Magnet Join Date: Sep 2003 Posts: 4,284 Location: Spanaway, Wa User is: OffLine	Re: Overheating? Hate to state the obvious but damn...did you check the coolant level???
	[Reply w/Quote]

07-24-2009, 10:56 AM	#3
bigb19812000 Registered User Age: 28 Join Date: Jan 2009 Posts: 97 Location: Zephyrhills User is: OffLine	Re: Overheating? my 2000 s10 had a similar issue and it turned out the heater hoses were clogged up with what looked like some kind of stopleak or something.So reach back to heater hoses and squeeze them if you here a crunching sound that is your problem.Also check your t-stat they go out all at one time sometimes .YOu can also look at the weep hole at the bottom of your water pump maybe it is on its way out
	[Reply w/Quote]

07-24-2009, 11:30 AM	#5
02Blazer Registered User Age: 31 Join Date: Jul 2006 Posts: 17 Location: Playa Del Rey, CA User is: OffLine	Re: Overheating? Thanks for the suggestions guys. There was nothing coming out of the weep hole on the pump, nothing dripping under the vehicle whatsoever. My SES light is not on. My coolant level is good, radiator is full. I'll have to check the heater lines later, I backflushed the whole system about 10,000 miles ago, so i dont think it would be an issue, but you never know... Is there a way to see if the sender is bad via resistance check with a multimeter? If so, what are the parameters of the test? Also with the thermostat, can i test that on the truck? I remember boiling the t-stat on my chevelle back in the day to see whether it was opening, just wanted to know if anyone had a different approach. Thanks all.
	[Reply w/Quote]

07-24-2009, 11:45 AM	#6
bigb19812000 Registered User Age: 28 Join Date: Jan 2009 Posts: 97 Location: Zephyrhills User is: OffLine	Re: Overheating? Quote: Originally Posted by 02Blazer Thanks for the suggestions guys. There was nothing coming out of the weep hole on the pump, nothing dripping under the vehicle whatsoever. My SES light is not on. My coolant level is good, radiator is full. I'll have to check the heater lines later, I backflushed the whole system about 10,000 miles ago, so i dont think it would be an issue, but you never know... Is there a way to see if the sender is bad via resistance check with a multimeter? If so, what are the parameters of the test? Also with the thermostat, can i test that on the truck? I remember boiling the t-stat on my chevelle back in the day to see whether it was opening, just wanted to know if anyone had a different approach. Thanks all. Take the t-stat out put the truck back together without the t-stat .Run it.if it gets hot it was not your t-stat . Last edited by bigb19812000 : 07-24-2009 at 11:49 AM. Reason: typos
	[Reply w/Quote]

07-24-2009, 08:45 PM	#7
Rhotpursuit Ticket Magnet Join Date: Sep 2003 Posts: 4,284 Location: Spanaway, Wa User is: OffLine	Re: Overheating? Quote: Originally Posted by bigb19812000 my 2000 s10 had a similar issue and it turned out the heater hoses were clogged up with what looked like some kind of stopleak or something.So reach back to heater hoses and squeeze them if you here a crunching sound that is your problem.Also check your t-stat they go out all at one time sometimes .YOu can also look at the weep hole at the bottom of your water pump maybe it is on its way out A clogged heater core will not cause it to overheat.
	[Reply w/Quote]

07-24-2009, 09:08 PM	#8
bigb19812000 Registered User Age: 28 Join Date: Jan 2009 Posts: 97 Location: Zephyrhills User is: OffLine	Re: Overheating? Quote: Originally Posted by Rhotpursuit A clogged heater core will not cause it to overheat. a clogged up any thing in the cooling system will cause it to overheat by restricting proper flow of coolant.so if your heater lines are clogged and still hooked up it will most likely overheat
	[Reply w/Quote]

07-25-2009, 03:13 AM	#9
02Blazer Registered User Age: 31 Join Date: Jul 2006 Posts: 17 Location: Playa Del Rey, CA User is: OffLine	Re: Overheating? So I got a chance to work on her tonight and me and pops figured we'd start small and move our way up. Swapped the thermostat out, fired her up and let her sit for a while, the gauge never moved past halfway, the t-stat did the trick. I’m stoked. Thanks for taking the time to help me out everyone, later!!
	[Reply w/Quote]

07-25-2009, 10:16 AM	#10
bigb19812000 Registered User Age: 28 Join Date: Jan 2009 Posts: 97 Location: Zephyrhills User is: OffLine	Re: Overheating? Quote: Originally Posted by 02Blazer So I got a chance to work on her tonight and me and pops figured we'd start small and move our way up. Swapped the thermostat out, fired her up and let her sit for a while, the gauge never moved past halfway, the t-stat did the trick. I’m stoked. Thanks for taking the time to help me out everyone, later!! glad it all worked out for you.Not to make you worry or nothing but soon after my t-stat replacement it was time for a water pump.SO keep an eye on taht temp and coolant level.
	[Reply w/Quote]