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After replacing headgaskets, im havin some real overheating issues. I don't know if maybe the wire for engine temp sensor is just reading hot or if the engine is actually overheating (see picture). I say that because the new heads were installed on other sides (old ones cracked) and they made a wire to reach the temp sensor on that side and with the aftermarket headers i wanna say its just making it read hotter than it is. It has brand new coolant sensor, new thermostat, new radiator cap, hooker headers, radiator is maybe 6 months old, new water pump, air dam underneath is removed. Any help or ideas to look at would be helpful! Also while getting the picture of wire attached to sensor, i saw thermostat gasket, figured i'd isk for thoughts on it, and ask what is the third wire in 3rd picture for.
That single-pin wire in your hand is for either the fan switch or the knock sensor.
If the wire is dark green w/ white stripe, it's for the fan switch. Which since it's in your hand and not plugged into the switch, might have some bearing on an "overheating" problem.
Put the temp gauge sending unit back in the head it belongs in (driver's side), and put the fan switch back in the head it belongs in (pass side) and plug it back in.
The thermostat gasket looks like a typical paper gasket, which of course never really completely seals. They usually end up with an accumulation of dried antifreeze substance like that. I screwed up one time back in the 90s and put Dex-Cool in my motor... every single paper gasket in the motor that sealed coolant - head, thermostat, water pump, WP cover, intake - had a frosting of pink-orange fuzz like that after just a week or so. Not much you can do about yours though, except coat the inner edge of the gasket with sealant, so that it can't wick through the paper as easily.
That connector in your hand in the third pic is either the second fan switch or the knock sensor. The knock sensor mounts into the passenger side block drain. The fan switch is up higher on the head if I recall correctly. The first pic is the temperature gauge sensor. That should be on the driver's side but I would think it doesn't matter if it is on the passengers side as the coolant flows the same through the heads.
You should tell is more about the over heating. While idling? Do the fans come on? Etc.
That connector may be either the fan switch or the knock sensor. Their connector looks the same.
If the wire is dark green with a white stripe, it's the fan switch. Not having a switch would prevent the fan from coming on under some set of circumstances or other.
Best thing to do if that's the fan switch wire, is put the temp gauge sending unit back in the head it belongs in (driver's side) and then put the fan switch back where it belongs and plug the wire into it.
If that connector is for the knock sensor, your Check Engine light should be on, and you should have a code for a knock sensor problem. If your Check Engine light comes on normally with the key on and engine not running (i.e. if the bulb works), then goes out when the engine is started, it's probably not the knock sensor.
Yup, connectors are the same, the color of the wire will tell. When he posts that we'll know for sure. I don't think the connector color is relevant at all.
The thermostat gasket looks like a typical paper gasket, which of course never really completely seals. They usually end up with an accumulation of dried antifreeze substance like that. I screwed up one time back in the 90s and put Dex-Cool in my motor... every single paper gasket in the motor that sealed coolant - head, thermostat, water pump, WP cover, intake - had a frosting of pink-orange fuzz like that after just a week or so. Not much you can do about yours though, except coat the inner edge of the gasket with sealant, so that it can't wick through the paper as easily.
Or, better yet: DO NOT USE PAPER GASKETS TO SEAL COOLANT.
Just clean the surfaces to the bare metal, and use black silicone. Thermostat housing, water pump, anything that sees coolant.
While I'm on the subject of gaskets, don't use cork gaskets.
Paper and cork gaskets are 1920's technology, and they have no place on modern cars.
Or, better yet: DO NOT USE PAPER GASKETS TO SEAL COOLANT.
Just clean the surfaces to the bare metal, and use black silicone. Thermostat housing, water pump, anything that sees coolant.
While I'm on the subject of gaskets, don't use cork gaskets.
Paper and cork gaskets are 1920's technology, and they have no place on modern cars.
I use blue, but yeah no gasket on the thermostat housing... just clean the metal and an 1/16" layer of silicone before mating the housing to the manifold. Excess squeezes out and i trim it off after it cures.
When he posts that we'll know for sure. I don't think the connector color is relevant at all. 
