Car not heating up to operating temp

[jackcramerr]

Hi

 

Noticed since a while that is250 takes much longer than any other car to come up to operating temperature. Is that normal? It gets there after 15-30 mins of driving. 50k miles. Is it time for new thermal valve?

[NemesisUK]

Yup, sound very much like the stat is stuck open.

[madasahatter]

Are you talking from cold? Does it get to temp at all. It could be thermastat but i can honestly say mine is toasty warm. But it does not get warm in 5

minutes shes a large engine. What are you comparing it to, 

[johnatg]

I wouldn't say 'any other car' but it's pretty normal for a IS250 - there's a lot of coolant to heat. My temp gauge starts to rise after about 1½ miles then takes another couple of miles to get to the normal half way mark.

My wife's Mii gets to full temp within a bit over half a mile.

My MX-5 is somewhere in between.

I'd say nothing to worry about.

[J Henderson]

Sounds quite normal to me too. My commute home from work each morning is about 12 miles and I'm usually most of the way home before the car feels fully warmed-up.

[Verbout]

1 hour ago, jackcramerr said:

Hi

 

Noticed since a while that is250 takes much longer than any other car to come up to operating temperature. Is that normal? It gets there after 15-30 mins of driving. 50k miles. Is it time for new thermal valve?

15-30 minutes of driving is a bit of a range.

[normski2]

Must admit that does sound a bit slow to warm.

Mine is warming within 2 miles and warm within about 4.

It's on the drive after start up for maybe 2 mins whilst locking house, stashing case and squeegeeing windows.

Squeegeeing .... what a great word that is 

[jackcramerr]

Weather is warmer now but I can safely say, 4 miles drive today made the needle be 3/4 to from the middle. So it never gets warm from my local short journey.

So long as I am not damaging the engine with it running cold, I can ignore it. Is it ok to do so?

 

The other car I had similar issue with but it was worse because driving that car at 70 in winters made the needle go well below the middle. I changed thermostate for that car and now it warms up within 2 miles. Actually warms up soon as I come across the first brae to work. Lexus is cold as a cucumber on the same brae. Even though with this car, the thermostate looked fine when I removed it. It was maybe opening earlier. In initial days, I saw the same behaviour as Lexus, it wasn't getting warm fast enough.

Is there any good way to check the thermostate without taking it out?

[madasahatter]

6 minutes ago, jackcramerr said:

Weather is warmer now but I can safely say, 4 miles drive today made the needle be 3/4 to from the middle. So it never gets warm from my local short journey.

So long as I am not damaging the engine with it running cold, I can ignore it. Is it ok to do so?

 

The other car I had similar issue with but it was worse because driving that car at 70 in winters made the needle go well below the middle. I changed thermostate for that car and now it warms up within 2 miles. Actually warms up soon as I come across the first brae to work. Lexus is cold as a cucumber on the same brae. Even though with this car, the thermostate looked fine when I removed it. It was maybe opening earlier. In initial days, I saw the same behaviour as Lexus, it wasn't getting warm fast enough.

Is there any good way to check the thermostate without taking it out?

All you can do is check inlet and outlet pipes from radiator see if they are both warm. Should also check the coolant is hot going into expansion bottle.

[is200 Newbie]

You should definitely see it get up to temp within the 4 miles.

The only issue I can see is your exhaust not getting up to temp to burn off the excess condensation and rusting quicker (not before your eyes but sooner than normal)

Try driving it using the paddles (manual mode) as it will heat up quicker, the coolant cools the auto box also so should help to heat engine up - you should notice a difference if not then you may have an issue.

Not sure how effective coolant is whenit needs changing, would have thought in time it would breakdown and not be effective in cooling the engine which is the opposite from what you are experiencing....

[Britprius]

Water has the highest coefficient of heat transfer. Anything added to water lowers the heat transfer rate. So plane water in your cooling system will take away more heat from your engine than antifreeze mixture. 

This means the engine will heat up faster with an antifreeze than with water. A long warm up period suggest that the thermostat is stuck open. Checking the top and bottom hoses to see if they warm together from cold will confirm this. if the top hose gets  hot with the bottom staying cold the stat is ok. Both getting warm means the stat is stuck open.

John

[jackcramerr]

I could see 4 houses coming out. One thin, might be for the reserviour, one medium which might be for heater and two same size large ones with one going on top of rad and other maybe bottom? The top is warmer to touch than lower one. The top one seems as warm as the one that goes to the reserviour. The lower one seemed to be cooler than top one. This was after 4 mile journey with needle lowe than 2/4  of the middle point. So engine never gets to operating temp with my daily millage. I used paddle shifts today.

[johnatg]

That all sounds as if it's operating correctly - I doubt that changing the thermostat would make any difference. It's not just a lot of coolant to heat up - the engine is pretty big, with two cylinder blocks etc - that's a good lump of metal to heat. And there's a lot of oil - that is important for cooling too - it takes time to warm up.

IS250s don't operate at best efficiency on short journeys - they need 10 miles or more. I use the Mii when I can for short trips of less than ten miles or so - it's easier to park, too!

[Rebecca]

The is250 can take a while to warm up. On my daily 4 mile commute to work during the colder months with the heater on full blast the needle was around the 3/4 from centre on arrival. 

With the milder weather now the needle reaches centre on arrival after 4 miles.

Smaller engined cars I've owned in the past warmed up nicely after a couple of miles.