Factory Water Temp Probe/sensor

[Wacky Dee]

hey guys I'd like to replace my factory water temperature probe/sensor ..the one that sits near the coolant bleed screw at the front of the engine. The reason for this it's reporting temps to the ecu (confirmed via consult) higher than my aftermarket gauge which has a temp sensor measuring temps on the same radiator hose only about 20cm distance from the factory one...

It's for an R34 GTT (rb25det NEO) .. if anyone knows the nissan part # and approx. cost please do tell Cheers

[Wacky Dee]

I got this part # from nissan over the phone .. 22630-44b20 Googling for it, it does look like the right part. The nissan guy I spoke did mention there's another 'sender' unit for the actual dashcluster gauge, does anyone know where this one is located? I changed my thermostat the other day and didn't notice it there anywhere

[blind_elk]

there's another 'sender' unit for the actual dashcluster gauge, does anyone know where this one is located? I changed my thermostat the other day and didn't notice it there anywhere

It should be right beside the ECU temp sender - it's the one with a single pin connection.

[Wacky Dee]

yeah thanks I worked it out yesterday .. that one is $63 and the ecu temp sender is $97 ...bit steep but worthwhile if unsure about the condition of the stockies which I am.

[Duncan]

I think its really unlikely there is a problem with a coolant temp sensor, they are a very simple thing. Is it well grounded? Any sign of trouble with the wiring (check continuity to both ends of the wire).

Much more likely the new gauge is wrong (probably not well earthed) than the standard one being wrong.

And the new sender is in the return hose to the radiator, not the one from the radiator right>

[Wacky Dee]

what do you mean by continuity? the other end of the wire is on the ecu loom ...

I've earthed the new gauge properly ..even had a sparky run a secondary ground to battery from the sensor. Both the factory sensor and my aftermarket one are on the top left radiator hose (inlet?) - 20cm distance between them. I will be replacing the factory sensor tommorow so I'll know soon enough if that was the issue

[Wacky Dee]

well it wasn't the factory coolant sensor ..$100 down the drain

The new ECT sensor shows the same temps as the previous stocko one .. still about 10 degrees Celsius difference between the factory and aftermarket sensor grrr. Gonna check with a sparky to see about the stocko sensor wiring...

[Duncan]

sorry very slow response. anyway checking the continuity of a wire makes sure there is no break hidden in the loom somewhere.

these senders work by increasing resistance to earth as they get hotter. if earth is bad they will give wrong reading (too low) which is the most common. If not that, problem in the wiring between gauge and sender. If not that bad power or earth to the gauge. Inany case an auto sparky should be able to sort it.

[Wacky Dee]

thanks mate that really helps

I've already figured out that my ecu factory sender was OK ..my cooling system temps have come down significantly since upgrading radiator/fan clutch.

My aftermarket gauge is still WAAAY off though but I just remembered I did one hell of a hack job on the power/earth connection to the actual gauge as the original connector broke and I had to improvise. Will need to fix that and I reckon the aftermarket gauge will be spot on just like the ecu one. Cheers