Car is a 2008 IS-F with 47k mi. Yesterday while playing around a little bit with my friends C5, I noticed the IS-F started to get a little hot. The oil temp gauge would go up one notch or so which I do believe is normal but the coolant temp gauge would get up to 3/4 of the way to Hot.

The car was being run pretty hard with several back to back wide open throttle runs. Although it was only about 15 minutes of running it hard. I noticed that the car also started to get real hot once before at an AutoX.

Once I started to drive normal again, the temp gauge came down to the normal range, right below half way. Keep in mind, I am in Texas so the outside temps were right around 100*. I don't believe this is normal tho for it to get this hot. I could beat on my Z06 hard with out it ever getting this hot and I don't think the IS-F would be able to take the abuse of a road course without it over heating, which doesn't seem right.

I checked under the hood and noticed my coolant level to be just a tad low. Still had plenty in the reservoir, but was at the low level. This brings up my next question. What kind of coolant do I need? I don't have a local dealership so I was going to check an auto parts store. The owners manual did not specify.

Thanks

 

u need toyota coolant cant use auto parts store coolant, well really i dont recomd it and have you gotten your fuel pump replaced, since i notice its an issue on the F

 

I did think about the water pump issue. The car was in the shop about 2k mi ago for a small coolant leak and Lexus replaced the thermostat housing. Did not mention anything about the water pump tho. I guess its possible it has started to leak since then.

I guess I'll make a run to the Toyota dealership today and get coolant.

 

Request a service history on your car, if you don't see any work done to the water pump then check for leaks, you may need to get that water pump replaced.

 

BTW, the C5 put a solid 3 cars on me from a 20-100 run

 

There's a serious problem with your car. I have tracked my car at Carolina Motorsports Park for 30 minutes at a time without cooling issues. Yes, the oil got hot with 102F outside temp, but I never saw the temperature gauge do anything abnormal at all - stable water temps despite high oil temps.

Sounds like you have air in your cooling system.

 

Added some coolant which I got from Toyota ($30/gal) so I'll have to keep an eye on it and see if it gets low again which will give me an idea if it has a leak some where.

 

Like Lobux stated above, it could be air in your system which would mean you need to bleed the system to get rid of those air particles. Maybe it was not bled right when you had the thermostat changed.

 

I second that with tracking. Don't think water temp. ever went past middle on mine.