hey im new to the forum and to the 7mgte...i own a mz21 soarer with a 7mgte in it....just havin a few problems with it...first of all im not dismissin the fact it might have a blow head gasket but ive done a compression test both wet n dry and it all came up good...lowest was 100psi and highest was 115psi.....but wen i was going thru the hills on night my engine overheated....i think i know the source of the problem but i wanna check...i have 3 fans apparently for the air con, one big one infront of the radiator and 2 small ones behind it, (my air con doesnt have a belt) but yeh these fans never turn on so would it have something to do with the sensor on the top of the thermostat housing (some one said it was the thermal fan switch).....because wen i earth this plug my fans will turn on as long as i have it earthed but once i take the earth off the fans switch off...so would it be the sensor and if so whats it called or would it be an earth problem? and would this be the source of the overheating...its only ever overheated that one time going thru the hills
ahh help with sensors!
- Thread starter sketchy_89
- Start date
If the fans come on when you connect the sensor/plug to a ground then your fail-safe is working correct. When your sensor goes bad the fans will be on all the time. So it's normal.
My air conditioning also has no belt and the fans never come on. It's due to the fact that :
1) the fans come on when you turn on on the aircon
2) the fans come on when the car gets too hot.
So maybe you should replace your water temp sensor ?
check the sensor as per tsrm: http://www.cygnusx1.net/Supra/Library/TSRM/MK3/manual.aspx?Section=FI&P=113
So as for your overheating problems:
1) do you have a fan shroud? if not: get one. if it's broken: get an other one.
2) check the condition of your visco fan as per tsrm. replace it if needed.
3) replace your thermostat if you're not certain that it's in good working order.
4) do you have enough engine coolant in your system?
5) in what current state is your radiator at the moment?
My air conditioning also has no belt and the fans never come on. It's due to the fact that :
1) the fans come on when you turn on on the aircon
2) the fans come on when the car gets too hot.
So maybe you should replace your water temp sensor ?
check the sensor as per tsrm: http://www.cygnusx1.net/Supra/Library/TSRM/MK3/manual.aspx?Section=FI&P=113
So as for your overheating problems:
1) do you have a fan shroud? if not: get one. if it's broken: get an other one.
2) check the condition of your visco fan as per tsrm. replace it if needed.
3) replace your thermostat if you're not certain that it's in good working order.
4) do you have enough engine coolant in your system?
5) in what current state is your radiator at the moment?
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hmmm nah not fixed..just gonna take it to a shop n get them to quote on everything that needs doing to it