Stupid Temp

[ghostlexus]

I have been searching for hours on forums, and I am looking for any updated information. Own a 92 es300. Recently have had overheating problems at slower speeds. Did radiator, t stat, new coolant etc. I am still overheating. The fan works and the power steering pump was recently replaced. If I am going from highway driving to city street driving, the guage increases dramatically (doesn't matter if heat or air is on). It goes from hot to about the 3 o clock position within 3 seconds of stepping on the accelerator, or I can put the car in neutral and gas it to drop the guage. Is there any way to diagnose a sensor problem or water pump issue. I don't understand how the temp guage can drop so dramatically in such a short period of time. Please help

Thanks

[Toysrme]

Eh, the information in the FAQ isn't correct. The 3vz's iron block, along with the way it's routing of the internal cooling passages is signifigantly over cooled. A lot of times they will bearly crack open, and not come close to opening the factory 190-212*F thermostats while they are cruising.

You can take a multi meter to the CTS. It's spec is 2,200-2,700 ohm at ambient (50-80*F), 250-350ohm (170-200*f) with the engine warmed up and idling.

That being said, sounds to me like you had a defective thermostat put in. Happens probably 25% of the time a new thermostat is put in a car. Be it the wrong thermostat, or the part simply doesn't work. That goes for OEM, and non OEM parts. Just one of those things. Go figure.

[VGR]

I've only seen 1 in about 20 OEM thermostats that were defective. Most of the time the problem is that owners and their mechanics fail to use the correct factory original replacement thermostat, thermostat gasket and fail to install the thermostat correctly because they jump into do-it-yourself work without consulting the factory repair manual.

The early 1990's 3VZ-FE engine takes the Toyota part# 90916-03075 thermostat and #16325-62010 thermostat gasket. The factory manual tells how the thermostat should be installed. Typically the "jiggle" valve on the thermostat needs to be aligned in a certain way to assure the cooling system will bleed itself of air pockets which can interfere with proper cooling performance. I don't have a factory repair manual either at the moment so I can't tell you specifically how the jiggle valve needs to be installed.

[xxxavier2k]

I have been searching for hours on forums, and I am looking for any updated information.  Own a 92 es300.  Recently have had overheating problems at slower speeds.  Did radiator, t stat, new coolant etc.  I am still overheating.  The fan works and the power steering pump was recently replaced.  If I am going from highway driving to city street driving, the guage increases dramatically (doesn't matter if heat or air is on).  It goes from hot to about the 3 o clock position within 3 seconds of stepping on the accelerator, or I can put the car in neutral and gas it to drop the guage.  Is there any way to diagnose a sensor problem or water pump issue.  I don't understand how the temp guage can drop so dramatically in such a short period of time.  Please help

Thanks

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I'm having a similar problem but I've realised that my coolant overflow tank is cracked and causes the system to lose pressure at that point (when the caps open). It's difficult for me to get coolant tanks down here so I repaired it and the overheating stopped...until it cracked again.

[SKperformance]

change the temp sensor as the best start as some have found it to be faulty

stick to OEM