Car Hitting Up To 104c On Warm Start

[Kwyjibo]

Hey guys,

Just looking for ideas on what could be causing my issue.

I recently installed new turbo(HKS2530), injectors, AFM, fuel pump, PowerFC and FMIC then got it tuned. Car is running great with no issues except for on hot starts.

Basically if I turn the car off in really hot weather, return to it in 5 minutes then drive it, in the first minute or so it has got as high as 104c, then eventually drops back to low 80's and even high 70's. I would generally blame my FMIC however it happens regardless of whether I stay still or start driving straight away at 80 km/h+. I should also note that I understand the FMIC is blocking air flow, however the car has never really hit over 86c even stopped in heavy traffic on a 37c day. All fans are working and I am 99% sure I bled the coolant system properly(done as I always do it).

Do you guys think I might have crap coolant or do you think the radiator is getting too hot when the car is sitting there with no water flow and this water is mixing with water in the temp sensor and heating it up very quick? Only other issue I can think of is that the HKS2530 that peaks briefly at 18psi runs much hotter than my old turbo and maybe increasing water temp?

If its not this then only solution I can think of is bigger/better radiator.

Cheers,

Adrian

[gotRICE?]

I would say its just because the cars sitting with no flow.

All the heat in the block is being absorbed by the water. So when you start it up for the 1st time the sensor will be hotter because of it.

Then once your driving it will drop because the thermostat is wide open anyway.

[shyr33]

Could there be a fault with the thermostat.....not opening properly or something like that? Although it's funny that it goes away after a minute.

[krzysztof]

first thing i would try is fitting a new nissan oem thermostat, if your still having issues after that try another coolant temp sensor.

[Kwyjibo]

first thing i would try is fitting a new nissan oem thermostat, if your still having issues after that try another coolant temp sensor.

I didn't think of the thermostat, may be opening slowly, I'll give it a go.

[blind_elk]

I really don't understand why everyone gets so het up when the temp spikes a bit while the car is stationary. Really, as long as the temp sits correctly while the car is moving, then there isn't a problem. And you can certainly save the $$$ you were intending to use to upgrade the radiator.

[Kwyjibo]

I would say its just because the cars sitting with no flow.

All the heat in the block is being absorbed by the water. So when you start it up for the 1st time the sensor will be hotter because of it.

Then once your driving it will drop because the thermostat is wide open anyway.

That's what I thought at first but if I flick the car off then switch it back to 'on' without running it, it only rises to 88c max, it's only once I start the car for the first minute it happens.

[mad082]

that would probably because the coolant has been sitting in the block getting hotter (from lack of flow) than it would normally and once you actually start the car the water pump starts pumping the coolant out you will see a spike in the temp until it normalises again. you could kind of think of it like walking on hot concrete with no shoes on. while you keep walking it is fine but then if you stop for a bit you will find that the concrete is much hotter.

[gotRICE?]

that would probably because the coolant has been sitting in the block getting hotter (from lack of flow) than it would normally and once you actually start the car the water pump starts pumping the coolant out you will see a spike in the temp until it normalises again. you could kind of think of it like walking on hot concrete with no shoes on. while you keep walking it is fine but then if you stop for a bit you will find that the concrete is much hotter.

That, was f'ing brilliant! Perfect example.

[Kwyjibo]

That, was f'ing brilliant! Perfect example.

Cool, well as long as the occasional peak up to 104c isn't damaging the engine I'm not fussed then.