My car temperature gauge keeps bouncing around from cool to red hot.?

Question

It is not consistent. Last year, I had a problem like that, but it would not cool down, so I had to get a new radiator. This is not the same problem because out of no where it will say it is hot, and then 5 seconds later it will go back. Someone told me that I might need a new radiator cap because an old one could screw up the pressure. Does that sound right? Can I just buy a radiator cap(lid) anywhere? Thank you

Answer 1

The most likely culprit is your thermostat. I would start here. Your thermostat is what "opens" and "closes" when your car is at different temperatures. ((which would cause your car to heat up (closed), then cool down (open).

the cap...maybe, but doubt it as it only purpose is to release excess pressure into the overflow tank.

Hope this helps. if you need any parts.. give me a yell logixautoparts.com -- we are cheaper than all the "big" stores.
:-)

Answer 2

Your problem is not a radiator cap. It is not a ground wire. It is air pockets in the cooling system. These air pockets move through the cooling system. When they pass the coolant temperature sensor, they cause the needle to drop, and when the hot water again hits the sensor, the needle jumps back up. There are two reasons this happens. First, the air pockets can be trapped in the system because the system was or is low on coolant, or was serviced improperly. A qualified mechanic would know that the system must be completely purged of air before it is considered properly serviced. Second, a compression leak caused by a cracked cylinder head or blown head gasket can allow exhaust gases to be forced into the cooling system, causing the same kind of air pockets. A compression leak can be identified by a qualified mechanic by installing a pressure gauge on the radiator while the car is running. A compression leak will cause the gauge to jump all over the dial.

Answer 3

My thoughts are that you have an intermittent ground loss and it is jumping when it makes the connection again
If you replaced the radiator, but not the cap last year, then I suggest getting a new cap and thermostat for cheap insurance.
But is probably a faulty temp sensor. I recently replaced mine and it came back on-line like it is supposed to be.

I doubt if it is the water pump, as a pump that is failing will not bounce between good operation and no operation, but rather it will fail slowly and progressively.
I do agree with the suggestion that you take it in and get the temp tested rather than taking a chance or you can go to a parts store and get a cheap guage and put it in, and test it yourself.
If all is well, replace the regular connection.

Answer 4

If it is a water pump problem, odds are that it will leak out of the weep holes and you will smell antifreeze and notice it is leaking. The thermostat is something that could be the problem, a ECT sensor, or even a bad head gasket. Get it checked ASAP, if it is running hot, the head can warp and and up costing more money then just a head gasket, sensor, etc. would. Is it using coolant? Any visible smoke?

Answer 5

a million.i might make darn particular, the radiator is crammed to the ideal whilst the motor is stone chilly. The coolant restoration bottle must be a minimum of three/4 crammed. #2. whilst replaced into the final time that the cooling gadget replaced into drained, flushed and wiped sparkling? #3. we don't comprehend the 12 months, make or type of your automobile. no count if it incredibly is a 1995 automobile or greater contemporary, mixing low value shop antifreeze with the generating unit fill of long existence chemical coolant will particular as heck plug the cooling gadget. If that has befell it is going to would desire to be wiped sparkling with a powdered acid cooling gadget cleanser.examine the specs web site of the glove compartment instruction manual for the right antifreeze the cooling gadget ought to have after it incredibly is been wiped sparkling. whether you have used no longer something different than the generating unit cautioned antifreeze, the gadget will assemble corrosion and rust over the years.

Answer 6

Good start to replace the rad cap , second though you might have a air pocket in the system or a lose connection on your sensor or a bad sensor

Answer 7

Doubt that is the problem. It is either a faulty guage (most likely) or a bad water pump. If you drive with the needle on HOT and it really is hot you could ruin your engine. Take it to a garage and have it checked out.

Answer 8

your cap might not be closed properly... your thermostat might trying to stick. you belt might be slipping. your fan clutch might be going bad. ( if you have a fan clutch).. the bearing inyour water pump could be going bad.

Answer 9

yes my cap broke to but it leaked fluid all over the place outside of autozone...just go but a new one like $3.50

Answer 10

happened to me once it was a hot spot caused by a blown head gasket