Focus Fanatics Forum banner

1 - 20 of 20 Posts

·
Registered
Joined
·
269 Posts
Discussion Starter · #1 ·
OK so i live in cali and right now its hottttt today was 106 in my area i have an ORP installed but when i bought it i didnt put the mil eliminator in he jus hooked the old 1 up and the light wasnt on so i was like coo but anyways its been hot and my cai has suckin up nothing but hot air so my car has been kinda slow is this ok? and is the light on b/c its the wrong eliminator? and my gas milage sucks right now im @ half a tank and i went 83 miles is this ok ive been shifting @ 4.5rpm lately i kno bad i have a heavy foot but do i need 2 b worried or not? thanks i kno im sort of pms'ing but jus let me kno
 

·
Registered
Joined
·
1,948 Posts
I dont know if the hot air has anything to do with the gas milage but it probably does.
Take the car on a night run and see if your gas milage improves.
Try shifting at 3k instead of 4.5k and see if that also helps, check tire air pressure,
air filter, fuel filter.....the works.
 

·
Registered
Joined
·
269 Posts
Discussion Starter · #3 ·
yea i jus got home right now and it felt fine like the power was there but during the day i dunno so it doesnt have 2 do anything with the off road pipe i jus got an oil change like 2weeks ago so i know the air filter, fuel filter tire pressure is all good
 

·
Registered
Joined
·
269 Posts
Discussion Starter · #5 ·
Hmm ur right r u still selling them for $350.00 I was thinking about it and I remember talking to you along time ago. I want a predator bad but I need to register for school 1st so can I buy one from you on 8/8 k.I.t.
 

·
Registered
Joined
·
1,734 Posts
You can't go by miles per tank, however I would agree that 83 to half a tank would be horrible!
 

·
Registered
Joined
·
11,906 Posts
As IAT's climb the ECU will add more fuel to help cool the engine, thats why you can get worse milage in hotter weather.
 

·
Registered
Joined
·
269 Posts
Discussion Starter · #9 ·
ok ok ok so basically its the weather right so there's nothing 2 b worried about?
 

·
Registered
Joined
·
11,906 Posts
I would still get the code checked just to be safe.

In our last hot spell... 100*+ and 90% humidity I got horrible gas mileage as well.. somewhere around 180 a tank full.
 

·
Registered
Joined
·
11,906 Posts
There are a few other factors that can change the amount of fuel being added to the "normal" tune, O2 reading, catalitic converter temps, ECT temps, air temps.... see where I'm going with this?
 

·
Registered
Joined
·
11,906 Posts
The hotter your engine gets, due to the factors I mentioned above and other that I didnt, the more fuel the ECU adds in to your tune.

Adding more fuel helps to cool the piston/cylinder which will bring your operating temperature down. The ECU will also pull timing to help keep temps down as well... its your cars way of sweating on a hot day.
 

·
Registered
Joined
·
269 Posts
Discussion Starter · #14 ·
o i didnt c ur comment above omg 180 a tank i think im going 2 get that. Imma buy a toyota tarius i heard they get 40mpg freeway. but i c thanks
 

·
Turbo!!!!
Joined
·
5,797 Posts
Are you still racing tonight?
 

·
Registered
Joined
·
406 Posts
Just to clarify things a bit, most modern OBDII cars will get better mileage on a hot day than a cold one. For several reasons.

Cold start to full warmed up time is much reduced in hot weather and this reduces the amount of enrichment before going into closed loop operation.

Once an OBDII car is operating in closed loop, the amount of fuel injected will result in a 14.7 A/F ratio....in part throttle cruise conditions. When the outside air is hotter, it is LESS dense and so less fuel is added to maintain the proper A/F ratio per rev. Also, being as the outside air is less dense, the total aerodynamic drag of the vehicle is reduced at whatever particular speed you are driving...compared to a colder day.

If you conciously drive for maximum mileage, you will find more on the hottest days compared to cooler ones. But, most of us don't drive strictly for max mileage and the hot days DO take a lot of power from the engine That makes us push the throttle open farther while acellerating and this consumes more fuel. And, at WOT, the O2 sensors are not in the picture and the engine is running off of a fixed (but adaptively adjusted) fuel/timing map that will probably be running the engine excessively rich as the map was made during cooler times.

A car that lives in 100+ deg temps everyday would likely show good (normal) mileage all the time. Those of us who endure ocassional very hot temps can show poor mileage if we try to drive the car hard when it is hot out. If we drive gently when it is hot, we will get good to excellent mileage.

Oh, the Prius CAN get over 110mpg if you drive it correctly. A group of guys recently did just that for an entire tankfull. 'Correctly' involved gently acellerating to 40mph then coasting back to 30. Repeat process for 1400 miles. No, we could NOT drive like that and survive in the real world, I just mention it to demonstrate that HOW we drive is more important to mileage than anything else.
 

·
Registered
Joined
·
269 Posts
Discussion Starter · #17 ·
yea witchcitySVT im about 2 leave my house right now im waiting 4 my bestfriend now he has a spec v and he wants 2 come to. RecoilRob ur right it was super hot so my car did feel slower so i did drive it harder but 90miles at half atank is alittle extreme
 

·
Registered
Joined
·
411 Posts
^^Hey super what school are you going to. I live In Pomona, Very close to Chino Hills. I also have a CAI and lately I have been noticing my mileage suckin. I don't agree with the guy above statement that the car should get better mileage on a hot day than cold. I do a lot of highway drving and have defietely seen a bit of a downturn in my mileage as of late which I hope is due to the hot weather. Hit me up bro maybe we could meet up and look at each others cars.
 

·
Registered
Joined
·
406 Posts
One other thing to keep in mind, regarding fuel consumption, is the fuel itself. The EPA has forced the gas companiies to dick around with the formulations in certain places and most of the changes have been BAD for gas mileage.

For example....are you running an Ethenol blend? 10% ethenol in the gas normally takes 2-3mpg away from our cars. Some places are forced into 20% blends which, of course, are even worse.

Theoretically speaking, all cars SHOULD get better mileage in the hot weather for the reasons I stated above. When some Government Wonks force you to use crap gas that kills your mileage, you should know why and blame them, not the cars.
 

·
Registered
Joined
·
269 Posts
Discussion Starter · #20 ·
hey i go 2 mt sac jus aim me SVTFsOnIcBlUe i fixed it i think i just unhooked my batter 4 30min and my check engine light was off and my milage is back to what it was
 
1 - 20 of 20 Posts
Top