Running Hot
 

General tech question.. my mothers little Mitsubishi Outlander is running hot whenever it sits to idle, meaning the temperature gauge needle is higher than it normally should be. In addition to that its leaking coolant, but there is more than enough coolant in the reservoir and it doesn't seem like its leaking that much, but I guess enough to run hot.

I pulled it outside to look underneath it and I couldn't find anywhere that it was leaking, I figured it was a hose. Any suggestions?

leaky gasket?

Funny you should mention that.. before I went to Kentucky the guy at the oil change place mentioned something about gasket and the pressure with the gasket was below normal... something that would eventually have to be replaced but I didn't have the money for it at the time. Would that make sense?

Head gasket?
 

Pressure - do you mean oil pressure? And was it a head gasket he mentioned.

Depending on the mileage on the vehicle, this could easily be the problem - and yes, having the fix done in a good shop is going to set you back some serious change, depending on the motor (what size motor is it, by the way).

He mentioned something about pressure, and from the looks of it he gave me a radiator cap... the silver one with the red warning sticker that says "Dangerous Hot"... car has 73,000 miles on it and has a 2.4 liter engine.

Under Pressure
 

The radiator caps can indeed control pressure. When they start to get weak, they can being causing trouble.

If the new cap wasn't the whole problem (and that's what it sounds like with the discussion about gaskets), but just a stop-gap delaying tactic, I'd recommend you call the guy back or consult the receipt (often these shop tickets have notes on them) and get back to us. Head gaskets can really ruin your whole day when they go.

73000 miles seems too few to need a new head gasket. I'd recheck what the fellow was saying - perhaps he was looking at the water pump, valve covers, water neck, etc.

I'd also be cautious to check the coolant daily and keep an eye on that temp gauge.

the radiator cap actually is pressurized. it raises the boiling point of the collant 3 deg. for every added pound of pressure.

Good data!
 

Absolutely. And they CAN go bad. But there's no gasket involved.

Well I don't know, I didn't give me any problems this morning besides no heat, and the gauge never left its center point, but its deffinately one of those things that you notice isn't right. I'm going to go bring it down to the shop and see if they can put it on the lift.

Just a follow-up it ended up being the water pump, thanks for the suggestions guys.