RRS with temp gauge spiking intermittently then drops please help

[ausitnsec]

HI I have a 2008 RRS white driving the temp spikes to highest level no red light.
It takes 5 seconds engine revving high when gas pedal pressed. then all of a sudden temp drops to normal takes 5 seconeds when it drops revving normal
Any Ideas?
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[joey]

First: has the antifreeze ever been changed? If so did the dealer do the work? If not it is time.

Sounds like an air bubble in the system. I would not recommend revving the engine with high temp even if that does fix it. One day it will just cause about $20k worth of damage.

 

[ausitnsec]

How do I remove the air bubble,

 

[ausitnsec]

The engine is just very loud when the temp is high
ten all of a sudden temp drops in like a 3 seconds and engine sound normal no revving.

 

[joey]

If an air bubble is in the system, park with the front of the rover at a higher level than the rear. Open the antifreeze fill, top off, close, start engine with heater on, run for about 5 minutes, let it cool. Then start over until it doesn't take more antifreeze.

 

[ausitnsec]

The only thing that does not add up is that the temp gauge rises from normal to hi n like 3 seconds and when it drops its also like 3 seconds , no way coolant would make it move that fast
wouldn't it be a sensor of some sort not coolant .
Just to be clear it is not a steady move it is extremely fast in doth directions.

 

[joey]

If it was an air bubble it could be... I always try to find the cheap option first when I can't see or feel the issue. If you have the Rovacom computer you could find out real fast what the issue is, but that would be a $10000.00 option just to check temp.

 

[ausitnsec]

I have a simple crp129 creader will that work .

 

[joey]

I may read what the ECU is sending, not sure what all it will see or can do.

 

[BeemerNut]

Are there any reasons not to connect a digital meter to the coolant temp sensor and read it during these "sudden normal to high temp" spike conditions?
It is quite possible to have a temp sensor reading air in an air pocket then get splashed with a different temp coolant changing the output signal within the above mentioned 3 second time frame.
Makes me wonder how hot that air pocket is above coolant temp as well the surrounding engine metal around the sensor before the big bang, boom ouch happen$.

95 D1, 4.6 w/chip, Bosch 4 hole injectors, port work 96 heads, intake and exhaust manifolds, one off 1 1/2" ram tube base extension, 5-spd, Borla exhaust, 255/65/16. Tached out at 4,400 rpm's in 5th (three tach verification) on the flat. Stock height HD springs, 190% front / 230% rear stiffer anti-roll bars, full urethane suspension.
Going fast on the straights and around corners with confidence.
Carl.....~~=o&o>.....