Quick jump in coolant temperature

[cralor]

Hey guys.

I have been having some tranny issues with P0741. I had my tranny rebuilt and my torque converter clutch replaced. I also had my radiator cracked and slightly leaking, so I replaced that as well.

However, I'm still seeing this particular issue. After starting the vehicle and driving about 2 miles, acceleration is directly proportional to the speed of my radiator fan and the noise it makes. (If it is not the fan, it is some loud "whirring" noise.) I watch the engine coolant gauge shoot up to max or near max and get the 'high coolant temp' warning light. About 2 seconds later it goes back to normal and I do not receive the noises associated with it anymore.

What might be the cause of this?

Thanks!

 

[Tech By Trade]

Air bubble in the coolant lines? They might not have burped it properly. Check and see if its full of rad fluid and give er a burpin.

 

[pzy3339]

if the fan is that loud all the time, even when the engine is not hot the fan clutch is stuck engaged. If it is on all the time because the engine is not getting enough cooling it could be a few things. Bad water pump, bad thermostat, air in system. I have also heard the air in system issue can mess with the temperature sensor and give false readings.

When I was having temp spikes it was the thermostat.

 

[cralor]

Might need to burp, I'll try that out.

The fan sound is only during this "period." When I begin to hear the loud fan, I know I can watch my coolant gauge spike in the next 15 seconds, and it remains in the H for about 1-2 seconds before going back to normal. Like I said, this happens after about 2 miles of driving almost every time -- and doesn't come back until a new cold start and drive.

 

[Duranged84]

Sounds like a sticking thermostat. Mine was doing that for a little while then stuck 90% shut. Ended up tearing thermo apart and putting just the sealing ring with oring back in for now.

I even boiled it on the stove for several minutes to watch it and only got about an 1/8 inch of movement tops after several minutes of boiling. Replace or tear it apart and put the sealing piece back in soon or you may risk an overheat.

These motors usually are easy to burp air, a few hot cold cycles should've already done it and your resivoir should be low. If its not low, I would say sticking thermostat most likely. If it is low, Top it off and watch the gauge again and watch the level in the res. A sticking thermostat will also cause you to lose some coolant even with a quick overheat like your getting. If you have to top it off more than maybe 2 times its probably not air trapped.