When it's hot out...

[brianmef]

I have a 2002 Mustang GT. When it's above 90 degrees out my car seems sluggish. Acceleration seems to take a lot longer. Is this normal? I feel like I lose 100hp. When it's cool out, it's just the opposite.

 

[281CI96Coupe]

Computer is drawing back timing...its normal, if you have an off-road pipe, it feels worse.

 

[Mustang5L5]

Isn't that normal with all cars when it's hot out??

 

[brianmef]

I've had older cars that didn't seem to do this. This just happens when the outside air is hot. If this is normal for the newer computer controlled engines, I would like to know what purpose it serves.

 

[Mustang5L5]

Just simple physics really. Modern fuel injected cars run on the hotter side than older carbed cars, so add on a hot day (humidity makes it even worse) and the engine gets hot to the point where detonation is probable. To compensate, the computer pulls time and adds fuel and you lose a little power.

Plus underhood temps heat up the incoming air which makes less power. And if you run the A/C it makes everything even worse. Mustangs are notorious for feeling like they lost 150HP when driven with the a/c on on hot days


Then when it cools off at night the car runs like a raped ape

 

[brianmef]

Thanks. That was a very good explaination. I understand better now.

 

[DTNODYA]

Just simple physics really. Modern fuel injected cars run on the hotter side than older carbed cars, so add on a hot day (humidity makes it even worse) and the engine gets hot to the point where detonation is probable. To compensate, the computer pulls time and adds fuel and you lose a little power.

Plus underhood temps heat up the incoming air which makes less power. And if you run the A/C it makes everything even worse. Mustangs are notorious for feeling like they lost 150HP when driven with the a/c on on hot days


Then when it cools off at night the car runs like a raped ape

+1

Cool air is less dense as well ...

 

[brianmef]

Here's a crazy idea. Why not channel AC into the air intake. LOL (just kidding of course)

 

[Gearbanger 101]

Hah! You think it's bad with your car, try driving a blower car in the heat. It feels like you've dropped a cylinder on the top end.

 

[40oz]

+1

Hot air is less dense as well ...

fixt.

 

[Wolvrin704]

Just simple physics really. Modern fuel injected cars run on the hotter side than older carbed cars, so add on a hot day (humidity makes it even worse) and the engine gets hot to the point where detonation is probable. To compensate, the computer pulls time and adds fuel and you lose a little power.

Plus underhood temps heat up the incoming air which makes less power. And if you run the A/C it makes everything even worse. Mustangs are notorious for feeling like they lost 150HP when driven with the a/c on on hot days


Then when it cools off at night the car runs like a raped ape

You drive my car too? When its hot out and the A/C is on I swear Bobby Joe on his 10 speed can take me sometimes, but at night its faster than greased lightning.

 

[brianmef]

Isn't cool air more dense?

+1

Cool air is less dense as well ...

 

[Modular2v]

Isn't cool air more dense?

yes which is why its better for combustion! Less dense air (like that found in denver) is going to slow a car down significantly!