Strange Temp Prob - Ford Forums - Mustang Forum, Ford Trucks, Ford Focus and Ford Cars

Rocket Ross · 03-05-2004, 03:35

Hi there

I have posted this once before on the main board but i thought i would have another go in this forum.. I have an EA 1990 EFI Auto and it seems to run within good temperature limits most of the time. Normaly it sits just on the very bottom of the NORMAL but ocasionaly in built up areas it will get close to half of NORMAL. The problem is that when i shut her down for 5-10mins and get back in her the temp is sometimes near top of NORMAL. As soon as i start the engine the temp drops to a resonable level.

Its very strange thet it would get hotter when its sitting and i was just wondering if anyone else has had or seen this problem? I had a landcruser once that did this but it was because the overflow was blocked, however, that doesnt seem to be the case here.

What Temp should A 3.9EFI run ? How could it get hotter when its not running?

Thanx heaps
Rossco

psycho chicken · 03-05-2004, 03:47

It heats up because there's nothing to cool it while it's not running. The water pump isn't doing anything, so only the water in the block/head is being heated and there's no flow of cool water from the radiator to cool it down.

It drops down again when you start it cos the pump puts all the cool water from the radiator in to replace the hot water.

ebxr8240 · 03-05-2004, 04:01

Its called heat sink where the hot parts of engine heat the coolant, then it rise's to top of head where temp sender unit is.It is normal so long as it comes down quick on start up..Check that clutch in fan is working o/k or fit E/L electric fans with relay and temp switch...

Rocket Ross · 03-05-2004, 04:12

Ok thanx guys.

I just realized that i posted in the same forum lol. I see what you are saying, its just that other cars i have owned dont usualy do this. It doesnt seem to be causing any trouble so i will let it ride till service time when my mechanic will have a look..

Thanx again
Rossco

psycho chicken · 03-05-2004, 04:22

As ebxr8240 said, it also has to do with the placing of the coolant temp sensor, which might be totally different in other cars you've owned.

It shouldn't be causing any trouble, the engine as a whole isn't heating up any more.