Is this normal??????

[Don Hiltz]

I have a 2000 Chrysler 300M and a 2004 Hemi Ram. In both vehicles, the heat rises until it reaches operting temperature and the needle stays there, even in stop and go traffic. The fan will come on and go off, but there's no significant change shown in the temperature guage.

In my Viper, the needle stays at the hash mark to the right of 190 degrees. In traffic, it slowly rises until it's almost in the yellow area. The fan starts and it slowly drops back to the right hash mark.

Is it normal for the temperature to flucuate that much????

Thanks....

Don

 

[Travis]

Its 'normal' for Vipers to run hot.

 

[PhoenixGTS]

I just got done upgrading my own cooling system and see the exact same phenomenon. The reason is that the fan kicks on at 207F on the way up then shuts off at 201F on the way down. When standing still, there is no air going over the radiator until 207F. Now that I have a monster radiator and pump in the car I would really like to lower both of these fan trigger temps about 10F. When West Coast Vipers reprograms PCMs they can do this, so once I kick Idle hang with their PCM for good I am going to have them lower the fan temps for me.

 

[97 B/W GTS]

I had the same question after I bought mine. Here's an interesting response:
http://vca2.viperclub.org/forums/showthreaded.php?Cat=&Board=UBB14&Number=499904&page=&view=&sb=5&o=&vc=1

BTW, I ran my car for a little more than 200 miles this last weekend. Some canyon runs....fast, slow, fast, slow. And also some easy freeway miles. The fluctuation was the same no matter how I drove. Between 190 and just past the first hash mark. About 75 degrees outside.

I don't think the needle getting to yellow is good.

 

[GR8_ASP]

In most cars the temperature guage is intentionally set so that minimal needle movement occurs while the temp is in the normal range. It is effect desensitized in that range. If you hook up a read tool to the OBD port you would find that most cars will oscillate between around 190 (t-stat start to open point (not the full open point) and the fan on temp (usually 225-235F).

The Viper gauge acts like a real guage (i.e. aftermarket) with a near linear response. What you are seeing is normal if it ranges from around 190 to 230ish (right side hash mark below the red zone).