WondrousBread

So most of the routine maintenance for my '86 NA Rx7 has been completed. Today we replaced the Thermostat. However, my car still idles at an uncomfortably high temperature and the problem does not go away at speed.

Basically, when I start my car it goes through the normal cold start sequence. The gauge slowly crawls up to operating temperature (1/4 on the gauge). My understanding is that 1/4 to 1/3 is the optimal temperature for a Series 4 engine. However, it does not stop at operating temperature. The gauge continues to crawl up until it hits the about halfway mark and then halts there and stays firmly where it is. There is no beeping, or any indication of temperature warning.

When driving, the temperature gauge goes between 50% and 60%. It does not go above 60%. The last drive we took was about 4 or 5 minutes long (approximately 1.5-2 kilometers). We drove down the road, intending to turn around when we got to town (we were trying to troubleshoot the cooling problem and see if it was better at speed). When we were nearly there, a steady beeping noise was emitted. We pulled into a parking lot and stopped the car, and after waiting for about a minute we drove back home. The beeping was gone until just the moment we pulled into the driveway. I would assume that beeping is a temperature warning, but I don't really know for sure. No warning lights on the console accompanied the beeping, and the exhaust overheat light remained off.

There is no white smoke (except when starting on a cold morning, and it goes away quickly), and the exhaust smells exactly like exhaust should smell (no burning coolant). There are no bubbles in the coolant, and no gushing coolant. We just refilled the coolant system with 50/50 and Water Wetter, and there was no change. I checked the fan clutch by attempting to spin the fan by hand when the engine was off, and the clutch seems to be nice and grippy. I did notice that there was no underpan between the rad and the bumper (which will negatively impact cooling at speed). I will order this part when I get a chance.

Background information on my car: Engine has about 10 000 km. It sat for about 2-3 years inside the previous owner's garage. The engine starts very easily, and aside from some dirty connectors and a slightly rough idle, it seems to have no problems engine-wise. All fluids and filters have been changed other than fuel filter (ran fuel through backwards and it came out squeaky clean, so I do not believe a replacement is necessary). It does nearly stall when turning on AC, and it does sometimes stall when stopping at lights. BAC valve is nice and clean, so I will adjust the idle again soon and hopefully solve that problem.

Is there a way to test the gauge for accuracy? I have to replace some light bulbs behind the cluster, so I don't mind removing it to test. It has been recommended to me to get an aftermarket gauge for a more accurate reading, and I don't mind paying for one, but I want to try and fix it with the stock gauge first. Also, where is the temperature sensor sender located, and how can I test that?

misterstyx69

iTrader: (142)

the stock gauge is crap anyways so really you won't fix anything even if it works like new.
It tells you absolutely nothing..no degree of temperature..just C and H..
Get an after market gauge and KNOW how hot the car is running.