Hey to All! Just joined the forum here - looking forward to the discussions. Driving an 2004.5 S40 T5.

I searched the forums for coolant/temperature related posts and found lots of info on the coolant temp sensor/thermostat issues, but didn't see anyone mentioning strange gauge/engine fan behavior.

Under acceleration and sustained speeds, my temp gauge rises about 2 notches and stays there until I let off the gas and reduce speed, which brings the temp reading down. Seems strange to me since if there was an overheating potential, then I would think less airflow would make the temp rise not fall. At idle/sitting still, the reading looks normal.

Also, engine fan continues to run for several minutes after shutting down engine. This is a new occurrence for this car. Oh, and CEL has not come on either.

Could this also be a symptom of the coolant temp sensor/thermostat going bad? Have any of you experienced gauge/fan behavior? Could it be something with the turbo?

Thanks in advance for your help!

 

I would check that first.(Thermostat and sensor)

 

Thanks, Tech. I'll definitely do that first.

If it turns out to not be that, any idea what else it could be?

 

Maybe something electrical maybe codes in the computer.

 

Hi, I have the same problem with my 850 T5 MY 1996.
Have you fixed it?
How?

Thanks,
claude

 

We have a spare car a Volvo s40 T5 2005 model that we purchased new , the fan always was on high after driving and then stopping but the temp gauge was always in the middle , but the temp gauge in the car is not accurate , connect a scan tool to the OBD and read the water temp while driving ,it does go up and down depending on engine load , which is normal from 90to 95 deg cel and to be fair some gauges will not move and others do , if the engine is working hard , like uphill etc the temp will always go up .the thermostat controls it but its not quick so one has always a small variant
But if it goes 2 notches up from middle when driving then its a problem and could be many things on a 20 year old car Faulty Gauge, bad radiator , worn water pump
When last was the water pump changed ?

 

The water pump, all water circuit hoses, all turbo hoses were replaced while repacing the timing belt in September 2024, some 5700 miles ago. My temperature gauge goes DOWN while hard accelerating, not up.

 

Ok so if it goes down ,on the temp gauge , is that at high speed with top gear , try same speed with lower gear if its ok then its the thermostat that is stuck open

 

I had the thermostat replaced not long ago, but it was probably not an OEM Volvo. I’ll put the old thermostat back and also replace the temperature sensor by a new one…

 

Before you do that connect a scan tool and select engine temp then go for a drive and see the actual temp read outs , these scan tools are not expensive now

 

Hi, I have the same problem with my 850 T5 MY 1996.