Help me diagnose this overheating problem please.
#1
TECH Enthusiast
Thread Starter
Help me diagnose this overheating problem please.
Hey all,
Quick question for you guys/gals.
My daily driver is an 02 WS6 with ~45K miles. I was driving to work today and temps were fine, never had any problems in the past.
Stopped at a red light and all of a sudden the temps started rising, fans turned on and check gauges light came on. Light turned green and I pulled away.
As soon as I started moving more than 10 mph, the temps went back down.
Pulled into the gas station and parked the car leaving it running, and the temps went back up again, fans came on, and check gauges light came on.
Drove the car around the parking lot and the temps dropped again.
I checked the coolant level and it was fine in the reservoir but a little low in the overflow tank. I haven't noticed any significant fluid leakage. Anyhow, I filled the overflow tank with water (that's all that was available) and left the gas station. However, I'm still getting the same problems.
Stop the car and it overheats, drive it and it's fine.
I drove the car 20 miles to the office without any problems overheating, but as soon as I got the garage and parked it started overheating again.
Any ideas? Could this be the water pump starting to go bad? Or possibly a sticky thermostat?
Thanks for the help,
Russell
Quick question for you guys/gals.
My daily driver is an 02 WS6 with ~45K miles. I was driving to work today and temps were fine, never had any problems in the past.
Stopped at a red light and all of a sudden the temps started rising, fans turned on and check gauges light came on. Light turned green and I pulled away.
As soon as I started moving more than 10 mph, the temps went back down.
Pulled into the gas station and parked the car leaving it running, and the temps went back up again, fans came on, and check gauges light came on.
Drove the car around the parking lot and the temps dropped again.
I checked the coolant level and it was fine in the reservoir but a little low in the overflow tank. I haven't noticed any significant fluid leakage. Anyhow, I filled the overflow tank with water (that's all that was available) and left the gas station. However, I'm still getting the same problems.
Stop the car and it overheats, drive it and it's fine.
I drove the car 20 miles to the office without any problems overheating, but as soon as I got the garage and parked it started overheating again.
Any ideas? Could this be the water pump starting to go bad? Or possibly a sticky thermostat?
Thanks for the help,
Russell
#3
TECH Enthusiast
Thread Starter
Yeah,
The coolant level in the overflow was a little low so I might have a small leak somewhere, but all the other indicators seemed like a stuck thermostat. Just wanted to check to see if anyone else has had the same problem.
Thanks,
Russell
The coolant level in the overflow was a little low so I might have a small leak somewhere, but all the other indicators seemed like a stuck thermostat. Just wanted to check to see if anyone else has had the same problem.
Thanks,
Russell
#4
TECH Enthusiast
iTrader: (2)
Join Date: Apr 2005
Location: Gold Country California
Posts: 572
Likes: 0
Received 2 Likes
on
2 Posts
I was plagued by that problem in my Vette'. It was worse though. It would puke all
the water out when shut off. I replaced the pressure cap and that solved the puking problem (who knew those go bad?). It still would overheat so I pulled the water pump and found a little spot on the back where air was entering the system but only leaked a very small bit. New pump (with new stat) cured everything.
the water out when shut off. I replaced the pressure cap and that solved the puking problem (who knew those go bad?). It still would overheat so I pulled the water pump and found a little spot on the back where air was entering the system but only leaked a very small bit. New pump (with new stat) cured everything.
#5
TECH Enthusiast
Thread Starter
Thanks for the info Lasershop!
I'm going to replace the T-stat and cap, flush and refill the system. Then keep very close tabs on the fluid level every day. If I see it leaking I'll check the water pump very closely.
By the way, any idea what a power flush will run me? Is it something that only the dealer should do or can I take it to a local shop?
Thanks again,
Russell
I'm going to replace the T-stat and cap, flush and refill the system. Then keep very close tabs on the fluid level every day. If I see it leaking I'll check the water pump very closely.
By the way, any idea what a power flush will run me? Is it something that only the dealer should do or can I take it to a local shop?
Thanks again,
Russell
#6
TECH Enthusiast
Thread Starter
Just thought I'd post back to let anyone who's interested know the outcome.
It was a bad thermostat. Took the stock thermostat out and the rubber gasket on the inner thermostat was corroded and causing the thermostat to stick. Replaced it with a new one and problem solved.
I'm pretty surprised the stock thermostat didn't last longer. I've only got 45k miles. My 77 vette still has it's stock thermostat and it's in perfect condition, same thing with my 97 Expedition (145K miles).
I did find a small leak however, behind the water pump when I pressure tested the system. Anyone know the water pump bolt torque specs?
Thanks all,
Russell
It was a bad thermostat. Took the stock thermostat out and the rubber gasket on the inner thermostat was corroded and causing the thermostat to stick. Replaced it with a new one and problem solved.
I'm pretty surprised the stock thermostat didn't last longer. I've only got 45k miles. My 77 vette still has it's stock thermostat and it's in perfect condition, same thing with my 97 Expedition (145K miles).
I did find a small leak however, behind the water pump when I pressure tested the system. Anyone know the water pump bolt torque specs?
Thanks all,
Russell
#7
TECH Enthusiast
iTrader: (8)
Join Date: Dec 2004
Location: Bellevue, WA.
Posts: 649
Likes: 0
Received 0 Likes
on
0 Posts
Well actually I got a kinda similar problem, I have no overheating but overflowing of coolant then I add more and it overflows again. Overflows till some point then not enough coolant to overflow, I've never had an heating problem tho. I am planning to change my thermostat too. Perhaps it would cure it, hopefully!
Trending Topics
#8
TECH Enthusiast
Thread Starter
Yekta,
I didn't have any overflowing of coolant, and it really shouldn't happen even with a sticking thermostat. The only thing that causes overflowing coolant is over-filling the system, or a leak. When there is a leak, pressure is not maintained and the coolant boils, causing it to expand and overflow. I'd go to autozone and get their rentatool cooling pressure tester and do a quick pressure test. It's easy and will tell you very quickly if you have a leak in the system.
Russell
I didn't have any overflowing of coolant, and it really shouldn't happen even with a sticking thermostat. The only thing that causes overflowing coolant is over-filling the system, or a leak. When there is a leak, pressure is not maintained and the coolant boils, causing it to expand and overflow. I'd go to autozone and get their rentatool cooling pressure tester and do a quick pressure test. It's easy and will tell you very quickly if you have a leak in the system.
Russell
2000, 2006, 97, expedition, idling, overflow, overflowing, overheating, park, problems, ss, tank, trailblazer, ws