I have done a search and need some advice plese fellas ...

 

 

all the info is on this thread ...

 

http://www.300zx.co.uk/forums/showthread.php?t=39918

 

 

Maybe someone with some sort of tech advice could reply ...

 

Ta

 

Chris

210 farenheit chris is just under boiling point for water, but that is not an excessive temperature for engines these days!

 

You could flushing your rad and refilling with fresh AF and a couple of bottles of water wetter

Hi Mark

 

Well all I can say is that I know my car and this isn't right.

 

I have flushed the rad completely, checked for air locks, used the correct combination of good antifreeze with water. The bottom pipe is cool to the touch, the top pipe hot. There is no oil in the water, clear as a bell and I don't have a coolant leak.

 

I am 99% convinced that it is the sender. I mean what is the point of going to all this trouble and expense, fitting the stainless top pipe and bottom, fitting the gauge only to be given *****x readings?

 

****s me right off.

210 farenheit chris is just under boiling point for water, but that is not an excessive temperature for engines these days!

 

You could flushing your rad and refilling with fresh AF and a couple of bottles of water wetter

 

If the water system is in good condition the 300zx should be running 75-85 degrees , imho 100 degrees is too hot , mind you as posted on previous threads putting the airconn on can add 10 degrees

 

Ryan

Exactly mate. I know the water system is in good condition, and as MAC says FACT.

 

Hence why I have contacted the manufacturers direcly because I am convinced it is the sensor.

 

Cheers Ryan

Just contacted a UK dealer for Autotechnic and explained everything in detail and they think it is the wrong sensor. :rolleyes:

If the water system is in good condition the 300zx should be running 75-85 degrees , imho 100 degrees is too hot , mind you as posted on previous threads putting the airconn on can add 10 degrees

 

Ryan

 

 

The zed always runs higher than 80 degress at least, after it is warmed up, while motorway driving the temp gets even higher, with consistent temps in the 90s, of course each zed has it's own characteristics!

The zed always runs higher than 80 degress at least, after it is warmed up, while motorway driving the temp gets even higher, with consistent temps in the 90s, of course each zed has it's own characteristics!

 

Disagree with this mark

 

A lot of zeds as you say run in the 90's but having driven a lot of 300's with Conzults etc most run 75-85 including my own , on the motorway they should run cooler not hotter unless you are really pushing the car , I still say if you are running at 100 degrees then your cooling sytem is not working efficiently

 

Ryan

Never heard of a zed running 75 degress before, since the thermostat opens at 76.5, are you talkiing about idling temp or running temp?

 

Unless you have an aftermarket rad or thermostat?

 

Yeah sure 100 degrees is not desirable and gives you less headway for error, but that is what cars are designed for these days.

 

It obviously depends on what speed you are doing, but Motorways can cause a problem in that air can be travelling too fast through the rad to cool it effectively, combined with the increased running temp of the engine.

My thoughts are that it should be running between 80 - 85 degrees on load and not pushing it. If you drove it hard then I would expect the temperature to go into the low 90's

 

210F is way too hot under normal load.

Ryan just in case you are getting running temps of 75, it could mean the ecu temp sender is faulty.

 

I believe this is, at 80ish degrees, meant to tell the ecu that everything is running correctly, if it is not sending that signal to the ecu then the car will not be running right.

If I remember, the cooling fan only comes on, on the Z at 105ºC and goes on to high speed at 115ºC

 

If the fan is only set to come on at those temperatures, anythink upto those temperatures are not abnormal

Ryan just in case you are getting running temps of 75, it could mean the ecu temp sender is faulty.

 

I believe this is, at 80ish degrees, meant to tell the ecu that everything is running correctly, if it is not sending that signal to the ecu then the car will not be running right.

 

LOL pretty sure my car is running ok Mark,

 

Mark , bare in mind I run no AC i.e all removed , I have a water bypass making the water system more efficient along with most of the casting removed when the engine was rebuilt , I also run very little coolant and run water wetter, all of this basically means that after very hard runs the temp drops back to the 80 degree mark very quickly etc, it also never goes above 90 degrees even in hot weather,

 

as for the temp sender being up the creak well both the conzult and after market gauge read identical temps , so I doubt it is faulty

 

Ryan

LMAO don't forget, anything stated in the service manual must NOT be adhered to as these cars are no longer new :rolleyes: :rofl:

something else to bare in mind is that the hotter the car gets the more the ECU retards the timing (not safety boost) just the timing so if your running at 95 degrees the chances are the ECU will have retarded the timing a degree or two.

 

Ryan

simple test:

 

drive for a while and let the car idle, turn AC on.

if the aux. fan switches on, the engine temp is 90Celcius or higher : engine is running hot.

 

turn off the AC.

if the aux. fan stays on : the engine temp is 105Celcius or higher : engine is (seriously) overheating.

As a second check you can switch on the heater at high temp and full speed, if the air coming from the heater stays cold, there is a airlock in the cooling system.

 

if the fan stays off in either case: engine temp is below 90 Celcius : normal operating temperature.

 

(the above is only applicable if you have a working aux. fan and a working coolant temperature sensor ;) )

 

Hope this helps.

Eric

simple test:

 

drive for a while and let the car idle, turn AC on.

if the aux. fan switches on, the engine temp is 90Celcius or higher : engine is running hot.

 

turn off the AC.

if the aux. fan stays on : the engine temp is 105Celcius or higher : engine is (seriously) overheating.

As a second check you can switch on the heater at high temp and full speed, if the air coming from the heater stays cold, there is a airlock in the cooling system.

 

if the fan stays off in either case: engine temp is below 90 Celcius : normal operating temperature.

 

(the above is only applicable if you have a working aux. fan and a working coolant temperature sensor ;) )

 

Hope this helps.

Eric

 

Eric

 

as the Conzult does not allow you to do a power balance test until 75 degrees is reached I am presuming that this is normal minimum operating tempreture ???

 

Ryan

simple test:

 

drive for a while and let the car idle, turn AC on.

if the aux. fan switches on, the engine temp is 90Celcius or higher : engine is running hot.

 

turn off the AC.

if the aux. fan stays on : the engine temp is 105Celcius or higher : engine is (seriously) overheating.

As a second check you can switch on the heater at high temp and full speed, if the air coming from the heater stays cold, there is a airlock in the cooling system.

 

if the fan stays off in either case: engine temp is below 90 Celcius : normal operating temperature.

 

(the above is only applicable if you have a working aux. fan and a working coolant temperature sensor ;) )

 

Hope this helps.

Eric

 

 

Hi Eric,

 

Thanks for the excellent reply on this. I took the car out a lunchtime and the temperature climbed to 210F / 99C. I then stoppped, let the car idle, turned on the Air con to max and the Aux fan did not swith on at all. I am presuming it works.

 

I also did the heater one at higher speed and nothing but hot air ...

 

Sooooo I do think the gauge is not reading right.

 

Chris P

Eric

 

as the Conzult does not allow you to do a power balance test until 75 degrees is reached I am presuming that this is normal minimum operating tempreture ???

 

Ryan

 

Ryan, according to several temperature related tables in the ECU, engine temperatures between 81 and 90 Celcius are considered most ideal. Anything below or above this range will cause a correction in either AFR's or ignition.

 

for auto's the idle "should" be ideal between 66 and 85 celcius, for manuals between 71 and 85 celcius, so I used 75 celcius in the software as an average for both

 

-Eric

Ryan, according to several temperature related tables in the ECU, engine temperatures between 81 and 90 Celcius are considered most ideal. Anything below or above this range will cause a correction in either AFR's or ignition.

 

for auto's the idle "should" be ideal between 66 and 85 celcius, for manuals between 71 and 85 celcius, so I used 75 celcius in the software as an average for both

 

-Eric

 

Cheers Eric :cool:

Lymon for zed oracle :D