Hot weather & idle

[rx7ben]

Took my car for a spin yesterday and popped in asda on my journey. When i got back to the car after about 10 mins i turned the ignition on and the pfc was reading 110 degrees, so i started the engine and the car wouldnt idle properly. The revs were bouncing up and down and droping so low (below 1000rpm) i felt like it was going to stall (but it didnt) as soon as i drove off and the temps fell it was fine.
 
Has anyone else had anything like this happen. I hope its not anything to worrie about.

[Grizzly]

Temps can be high in hot weather.

[Jus]

I always cool mine correctly (water temps) before leaving the car for any length of time. I normally turn off the engine then put on the A/C so all the fans run, then re-start the engine as soon as the temps reach say, 90C. run it for 30-60secs and turn off. you will be amazed how it cools the water temps. High Intake temps are a real pain in the ass, not a lot you can do about it other than driving it carefully until the temps drop under say 40C.

[rx7ben]

Thats not a bad idea i"ll give that a go. When i pull up at home i normally leave the bonnet open for a bit. This helps allso.

[Jus]

Might help with heat soak but you want to try the re-start for water temps.

[SiH]

When you say the PFC was reading 110, do you mean water or air temp?

[SmbFD3S]

Yep mine does this too, after switching off for a bit and heat soak gets to the water temp sender, anything above 105 and the car rev\'s itself until it drops below 100, no idea why.....

[rx7ben]

When you say the PFC was reading 110, do you mean water or air temp?

 
Water temp mate.

[Aubec]

I think its revving it just to get the water pumping round through the block - when the engine is off the water just sits in the block and rad, heating up as it soaks heat out of the metal (to crazy temp sometimes, I\'ve seen 133 degrees with the engine off!), but not being able to transfer it anywhere as its not circulating through the rad.
 
I dont worry about it on the basis that if the water is getting hotter, the block is getting cooler and if its switched off there is no heat source to get the block up to dangerous heat levels.
 
Mine does the same thing if I switch off and re-start after a hard run - revs dont actually drop below my normal idle which is ~800rpm.

[ashc]

might have been a mini/nearly flood if you only went a short distance?
temps are fine thats normal for heatsoak, you wouldn\'t want to see that when it is running though.