Has anyone experienced any issues with their G running sluggish in the heat? I'm talking about ambient temps in the 90+ range. Sorry if this is a repost. I searched here, google, and a few other forums but haven't found anything.

Mine seems to start running poorly once the engine is good and warm and the temps are in that 90 and above range. Mostly low RPM performance. It just doesn't have any guts off the line or cruising on the freeway. Needs to rev higher and/or downshift more often to achieve normal acceleration. My dealer replaced both of my throttle bodies in an attempt to fix the issue. That comes with both air intake temp sensors and throttle position sensors. So far that hasn't helped at all though. Does anyone have any good ideas for me? Thanks!

 

all cars run kind of sluggish in the heat.

 

I didn't think it was that bad. The car definitely like cool air temp and felt more eager when you press the "Go" pedal, but its not like its day and night difference.

May be switch the brand of gas that you are running but keep it 91 or higher?

 

nope. i feel it too op. it got up to like 105 here with 80-90% humidity in Oklahoma (hate this place) and the throttle response was definitely affected. but i feel its to be expected with temps that high.

 

It is a little theory we call heat soak. Your intake air temp increases significantly, radiator needs more energy from the fan to cool engine internal fluids, etc etc.

Heat ruins all cars and you will typically see it called "Heat Soak"

 

Cold air is more dense. IAT, MAF, ECU, etc.. sees that denser air and a lil more fuel is added. More air + more fuel = more power. Trade off though for lower MPG's. Usually 10 - 15% less than summer. "There are several reasons for that, some of the most relevant ones are listed below.

Warm air

There's a scientific explanation for why you use less fuel in warmer weather, and it's to do with air temperature.

As you may know, your engine uses air, as well as gas, in order to generate energy. In fact, it uses huge amounts of the stuff, though only the oxygen is used in combustion. These oxygen molecules combine with carbon in the fuel during combustion, to form--you guessed it, carbon dioxide.

Anyway, one property of air, like many substances, is that it expands when it warms. This makes it less dense--molecules of the various gases are spread further apart. This means that every gulp of air your car is taking during combustion has less oxygen in it at warmer temperatures, and if there's less oxygen, the engine compensates by using less fuel.

This is bad from a power perspective, but good for economy. The engine is combusting less fuel due to the warm air, improving fuel economy. During winter, the reverse is true--denser air encourages the engine to chuck in more fuel, boosting performance and harming economy."

 

i'm sure there is a measurable difference but I don't think you'll notice it too much unless you are sitting in traffic and then get an opportunity to get on it.