97 Impreza OBS temperature

[HASx11]

Hello I have 97 impreza obs with 252000 miles where the temp gauge is fluctuating between At temp and 3/4. The hottest it got was 226 and it does no matter the speed but worse when driving around town. It is a gradual rise in temp it doesn't rise until driving for awhile it won't at all if I have the heat on full blast. I was thinking possibly it is the thermostat but I know these engines can develop headgasket issues towards this mileage. just wondering if my thinking is correct.

 

Thanks,

HAS

[1 Lucky Texan]

first, keep an eye on fluid level IN THE RADIATOR - don't rely on the overflow level.

 

is the overflow bottle filling up or overflowing?

 

are the fans working? is the car more likely to overheat at a long light or waiting for a train?

 

some folks have found a lot of debris/bugs trapped between the rad and the a/c condenser.

 

is the thermostat OEM-style? it matters;

 

 

[HASx11]

I am not sure on if it is oem or not but I have owned the car for three years without issue and I know the guy who worked on it before I owned. I should have mentioned I have been cheking the coolant level via radiator I learned that lesson when I was 18 and I filled the overflow bottle instead of the radiator and blew the engine on my dad's Nissan altima. No visible leaks or loss of coolant to my eye. I believe the fans are working at least they where when I checked at the start of the issue. The car can idle all day without issue seems to be more when I am driving between 20-40 miles an hour but still happens less often at other speeds. I plan on replacing the thermostat with an oem because I don't know when it was last done in the car and to see if it's my issue

Edited January 9, 2018 by HASx11

[1 Lucky Texan]

on the older cars, ground connections may need to be refreshed to keep sensors working accurately - disconnect, scrub all surfaces with a wire brush, reconnect, maybe coat with dielectric grease. they are all over the place under the hood - near the pitch stop mount center of firewall, intake manifold, fender, strut towers, etc.

 

but, it seems you know the engine is actually getting hot? when it's overheating, any bubbles coming out?

[Numbchux]

I think that car should be a 2.2, not common for head gasket failure. And head gasket symptoms usually get worse with speed, and involve coolant loss.

 

I think the easiest thing to check (although it seems fairly unlikely), is whether the fans are coming on. When it's good and hot, stop and pop the hood and see if they're both running. It doesn't take much driving at all to push enough air through the radiator, though. I had a failed fan in our Outback 3.0 for over a year and the only time it ran warm was offroading in June, slow trails with lots of trees and the A/C on....

 

 

Thermostats very rarely stick shut (I've honestly never seen it, and I've tested several), but it's cheap enough, and some fresh coolant can't hurt.

 

I would also recommend pulling the radiator when you have the system drained, and make sure the fins are clean. The fins are spaced out more in the A/C condenser, and debris can accumulate between them blocking the airflow.

[HASx11]

I'll take a look at the grounds and check the fans again. There is no bubbling in the coolant that I have seen. I have a code scanner that allows me to run diagnostics so I drove around until it started to rise and was able to see the temp rise. The car does have a couple electrical glitches such as my dome light only works on door not on and my windshield fluid sprayer works intermittently. I was able to get it to start to overheat by just turning off the heat on my car and I could get it to drop by putting it back on on high.

[1 Lucky Texan]

if the lower hose is very hot, could be a partially clogged radiator I guess.

[HASx11]

Checked fans they both work, the lower radiator hose was cold no lose of coolant I'll check again once it cools down no bubbling in overflow but I noticed the overflow is near the top full also both fans were running the whole time once it was at temp with ac off or on

Edited January 9, 2018 by HASx11

[lmdew]

Put a Subaru Thermostat in it.  While you have the coolant drained you could put a garden hose in the upper radiator hose and check the flow out of the radiator lower hose to make sure the radiator is not plugged.

[HASx11]

So it ended up being the thermostat it was not a oem one. For an aftermarket one it lasted more then 3 years and 60k plus as I am not sure when it was last replaced. Who ever replaced it last though used a lot of gasket maker it took a good amount of scrubing and scrapping to clean it all up. The car is running good now I'll keep an eye on it for awhile to be safe. Thanks everyone for the advice and help.