I have a 1995 Tacoma. Regardless of ambient temperature and driving conditions, the OEM temperature gauge never moves from center. I know from owning other cars that engine temperature can fluctuate greatly even in a properly working cooling system. I have a 1997 Land Cruiser and I noticed this same behavior on the Land Cruiser temp gauge as well. I spend a lot of time on the Land Cruiser Website (IH8MUD.com), and the guys there looked into it and found out that Toyota installed a "zener diode" on the temperature gauge to give it a "flat spot", so the gauge stays stable at any temperature between 190 and 230. The gauge only starts to head north when the engine temperature exceeds approx. 230 degrees. See thread for modification here:
http://forum.ih8mud.com/showthread.p...perature+gauge
After a LOT of experimentation it was finally determined that this very inexpensive mod will fix the OEM gauge by replacing 2 diodes in the temperate gauge with diodes you can buy in Radio Shack for about $2.00.
My question is has anyone noticed and or discussed this "flat spot" on their Tacomas / 4Runners? Has a mod been develpoed to fix this? Does anyone think the mod would be the same? I realize that an aftermarket gauge can be installed, but I see no point in installing ANOTHER gauge in place of the OEM gauge that should be workng properly.
The floor is open for discussion.