Has anyone had a problem with there car getting up to 218. I don't no why but it just got super hot today. It was only 80 outside so this should not be necessary. There is plenty of coolant in the over flow bottle. It is possible that it might be the fans. Any one else have any ideas?

 

Yep they all do you are fine.

 

you only need to worry if you go over 230...i think at 225, the radiator fans kick in at their highest speed. 225 is the highest ive ever seen, but its pretty common for me to be above 200. i hit 215 on the way home from the gym today

 

You're fine. Outside temp has less to do with your engine temp than airflow. You can overheat in below freeze weather if you don't have enough airflow through the radiator. But like others said, you can get up to 230 in certain conditions before the car kicks its fans to max. Also, you don't have to worry about any damage until over 260, providing you have the right coolant / water mix.

 

wow i dont think mine has ever reached 205... my wifes 2.2 got to 214 once but wow thats really high

 

Yeah my fans wont kick on. Do you guys know where the fuse is or what it might be labeled? I had to tear my supercharger off to get a bolt i droped yesterday. I dont see what i could have missed hooking up.

 

This is one reason for a tune. My 2.2 turns the fans on full blast at 198 so the car doesn't get that hot anymore

 

The PCM commands Low Speed Fans ON under the following conditions:

• Engine coolant temperature (ECT) exceeds approximately 106°C (223°F).

• A/C refrigerant pressure exceeds 1 310 kPa (190 psi).

• After the vehicle is shut off, the ECT at key-off is greater than 140°C (284°F) and system voltage is more than 12 volts. The fans will stay on for approximately 3 minutes.

The PCM commands High Speed Fans ON under the following conditions:

• ECT reaches 110°C (230°F).

• A/C refrigerant pressure exceeds 1 655 kPa (240 psi).

• When certain DTCs set

When the request for fan activation is withdrawn, the fan may not turn OFF until the ignition switch is moved to the OFF position or the vehicle speed exceeds approximately 10 mph. This is to prevent a fan from cycling ON and OFF excessively at idle.

 

I just got a tune and we set the fans to come on sooner. However the overheating occoured before the tune and it is still happening.

 

One very key thing here is the A/C pressure.

To test your fans turn on the A/C for a bit and see if they kick on, that's one way to cool the car at the drag strip between runs.

 

If the car doesn't get above 230 F ~ 235 F you aren't overheating.

Are you sure you set the fans correctly?

 

i live in south florida and see 180 while driving...

no more than 190 if i get to a light after driving hard hard and sitting...

 

I typically see 180~190. The car doesn't instantly heat up, but if you sit and idle for 3 or 4 minutes you will see the temps start to climb. No airflow through the radiator = no cooling. On the SS/SC it isn't the coolant tempurature raising that you have to worry about after hard runs anyways, it is the IAT2 temps.

 

Well it is the temperature sending unit, I guess thats what ill call it. If you disconnect the wire next to the hard line that carries coolant into the upper radiator hose, the sensor on the cylinder head next to the valve cover. The fans run none stop with that plug disconnected. The fans turn on with it unplugged so the sensor must be bad because it wont tell the fans to turn on. I ordered a new sensor from GM (20.00$), Ill let you no if that fixes the problem.

 

If you are getting a coolant tempurature readout on the DIC, the coolant temp sensor isn't bad. I am almost willing to bet that when the fan settings were changed, they weren't changed correctly and that is why they aren't coming on when you think they should be.

The coolant temp sensor sends the tempurature to the computer, computer then determines whether to switch the relays on or off to cycle the fans. If you are getitng a readout on the DIC, the sensor is sending the temp to the computer. Since you unpluged the sensor, which set a code in the enable fan DTC list, the computer activated the fans which means the fans and relay for high speed fan operation are working. It could be possible that the fan relay for low speed is bad, but if you set the high speed and low speed activation for the same time then it should never kick into low speed.

For those inquiring minds regarding changing the fan settings, here is my fan setup:



The top right, FAN Desired % vs. ECT is where you instruct the PCM what temp you want the fans to come on. That table references the FAN State Transition Desired % vs. Current State table to see when to activate each step. It is important NOT to change the FAN State Transition Desired % vs. Current State table, this will screw everything up possibly causing the fans to either not come on at all, or causing them to run ALL the time. The bottom left table is FAN Output Control vs. Current State which is the table you cahnge if you want to disable low speed fan operation and make the fans run at high speed all the time.

Looking at the way I have it set up - in the FAN state table we see 0 to 1 activates at 53 and 1 to 2 activates at 68. In the FAN desired table I have the low speed fan (0 -> 1) set to activate at 207F signified by the 54 in the column under it (this is 1 + the 53 in the 0 -> 1 in the FAN state table). When the temp reaches 207 the FAN State table recognizes the value is now higher then the current setting, and references the FAN Output Control table which shows that at a setting of 1 (the top row) Fan Output 1 (low speed) is set to 1 (on) and Fan Output 2 (high speed) is set to 0 (off). If you also set Fan Output 2 to a 1 this will command the PCM to activate the fans in high speed, bypassing low speed. Then you see that 1 -> 2 is set for 68 so in the FAN Desired table you see at 221F it is set for 69, so that is when my fans kick on to high speed as seen in the FAN Output Control table under 2 on the top row showing Fan Output 1 is a 1 and Fan Output 2 is a 1.

As a note - if you want to fans to run all the time (which isn't recommended at all) you can set a 1 into the Fan Output 1 (and Fan Output 2 row if you want them to be high speed all the time) row under the 0 (where it is currently 0 in all rows). This will make the fans come on any time you are under 15 miles per hour regardless of the engine coolant temp.

 

Mine never got that hot even without the heat exchanger