Thermostat??

[PWGUNNY]

My 2004 V6 sport has been very good to me since I wheeled it out of the showroom 11 years ago. I just passed 140k miles on it. The temp gauge has never moved past the middle in all these years. About a year ago I had a small leak in the radiator, so replaced radiator, water pump, thermostat, hoses, and did the timing belt.

Today driving to work, I noticed the temp guage way up and climbing. I pulled into a parking lot and let engine cool. I popped the hood and did not see any signs of overheating. No ticking, leaking, smoking, odor, and the car ran normal. I did not open radiator cap, but overflow had antifreeze in it.
After 15 minutes I fired it up and drove the remaining 4 miles to my office. The temp guage stayed in its typical center mark.
Now I'm puzzled. Thermostat? Sending unit?
I was going to buy a thermostat and put it in tomorrow, but this thermostat is about $65 at the parts store since it is integrated.

I'm leaning towards just swapping it out. Any advice on this?

 

[Jas2171617]

When replacing radiator, you replace cap also? If yes, was replace thermostat OEM?

 

[PWGUNNY]

I don't remember if the cap was replaced. The thermostat was likely OEM, but I will go back to my purchase history to see.

The cap? Could this be that simple?

 

[blind squirrel]

I would say thermostat is the culprit. I assume you have a v8 too right? If you changed the timing belt that is. Unless the 04 v6's had belts, but I thought the 6s had chains.

 

[PWGUNNY]

I don't think I replaced the cap, as it wasn't on the invoice. I likely used the original cap. The thermostat was made by STANT. Details:

OE Exact Water Outlet Assembly seal included; 180º (1-11/64" x 1-7/16" x 3-holes) w/Jiggle Pin, Seal




Jiggle pins and check valves for air venting, integral seals, and integrated water outlet housings are exactly like the original equipment




Type

Integrated Housing Thermostat



Outlet Inside Diameter (in)

1.17



OE Exact

No



Temperature (F)

180



Electric

No



Outlet Outside Diameter (in)

1.43



Number of Bolt Holes

3



Number of Seals

1



Jiggle Pin

Yes



Check Valve

No



Outlet Inside Diameter 1 (in)

1.141



Outlet Outside Diameter 1 (in)

1.353


Blind Squirrel- It's V6, and it was the drive belt.

 

[blind squirrel]

You might be thinking of the serpentine belt. Your truck has a chain for the timing.

Does my vehicle have a timing belt or timing chain?

 

[chompster4runner]

Make sure the cooling system is free of air by bleeding it.

 

[PWGUNNY]

You might be thinking of the serpentine belt. Your truck has a chain for the timing.

Does my vehicle have a timing belt or timing chain?

Yes. You are correct. My mistake.

I took the car out at lunch and the 12 mile drive to the store it was ok, coming back to the office the temp guage spiked 3 times but came back to normal within a few seconds.

 

[fdbyrne]

You really should quit driving it if at all possible. It doesn't have to heat up too much for too long before you will cause irreparable harm to your head gasket.

 

[truckhigh]

in my experience the stant thermostats and caps were terrible. if it were me i would replace with oem.

But, when you say spikes its it like a trippy gauge or is it spiking up and then cooling down.

 

[Jas2171617]

Overtime, the radiator cap tend to not working properly, replace with OEM. Thermostat of OEM it opens at optimal temp so the best MPG. So if it is need to be replace it, then so. The serpentine belt it has the tensioner to it, replace when it to old is a good preventive care along with the coolant, I used Zerex asian formular. Good luck.

 

[PWGUNNY]

Update:
After the initial shock of seeing my temp guage shooting up. I was not able to visibly determine what the issue was. I drove the truck locally for 3 days while keeping an eye on the guage. When I eventually saw the guage spike again, I parked the truck and finally saw some coolant leaking from the left side on the seam of the radiator.

I took the truck to a radiator shop and they replace the radiator. $365 later the truck seems ok, but I'll be focused on that temp guage from now on.
The replaced radiator was 13 months old, and purchased from Rock Auto. I submitted a claim through their warranty dept. and they will let me know tomorrow if I'm entitled to a refund. The radiator was warranteed for 1 year.

 

[truckhigh]

good to hear.. ill stay away form rock auto radiators.

 

[Jas2171617]

It is great when you know what was problem. Was you bougth the last radiator OEM?