L21 Vortec problems

[raymond mckinney]

Hey guys i have a 2000 C6500 454 Vortec and it had been having a reduced engine power problem for awhile but you used to be able to shut the truck off and restart it and it would run fine again, now it will only run ok for acouple minutes and go right into reduced engine power. The only code that showed was a coolant sensor. I have looked everywhere for this sensor i cannot find it. This truck has the coil per cylinder set up and has a tall water pump so the sensor is not where the l29 vortec sensor is. Ill take any help i can get!

 

[CodyB]

I may be thinking of the LS location, but I thought the coolant sensor was in the center of the block either on the driver or the passenger side beneath the headers sticking strait out. The 454 may have it in an entirely different location, just trying to help out a little.

 

[raymond mckinney]

Only thing under them on this motor are the knock sensors. Any more thoughts?

 

[raymond mckinney]

Nobody?