Was having some cooling issues. Turned out my fan wiring was fubar but in the process of figuring that out I discovered that the Mr Gasket 4363 160 degree thermostat (available at Advanced Auto) fits the SC400. Its a little bit smaller than the stock part but fits and most importantly, it seals.

Actually a little bit too cold for the current weather but should be great once it starts heating up.

Also got the cheap Hayden fan controller which seems to work well with my 94ish Camry electric fans.

KC

 

At 160 degrees, doesn't the car stay in open loop mode?

 

Nope. Takes longer to warm up and the temp fluctuates a bit more but it goes into closed loop. It's still usually in the 30's when I leave for work and it goes into closed loop. I'm actually monitoring the VF reading (which is the feedback control from the 02, hard to explain) so I can actually see it.

The stock thermostat is 180 so it's not really THAT much colder.

Edit: Now that I think about it, closed loop comes on way before the car actually warms up. It would be better to say that it takes longer to get to a "warmed up" idle. Part of the point of having heated 02's is so that the ECU can go closed before the engine is warmed.

KC

 

Oh okay, I see.

I think I remember reading something in the repair manual stating that for the ecu to start going into closed loop, there would have to be certain conditions that must be met. For example, ECT must be at a certain temperature.

But I do understand feedback control for the O2's. It makes sense that if it can get accurate values then of course the output is input dependent and at that point it truly is in closed loop.

Just clarifying because I have a 170 degree thermostat and my temp needle sits pretty low sometimes. Figured 160 would be even lower.