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Discussion Starter · #1 ·
Does some one knows if having shorts trips on my 2007 2.4 Eclipse is killing my fuel efficiency?
i'm having like 1.5 miles trip to my work and back to home (3 per day) having like 13 mpg avg(city drive mostly)

due to costs and security i cant take another way to transport, what i can do to improve it a little more, maybe let it warming for a couple o minutes before driving?

btw like a week ago removed my catalytic(it was broke..going to put a new one soon) and it improved my MPG from 9 to 13 ..
thanks..
 

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Basically Stock
2009 GS Turbo. 2007 GT
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Yes, expect short city drives like that to have awful fuel economy, as the engine has to add extra fuel to run properly when cold (standard across all gas engines). It's also retarding ignition timing to send extra heat and fuel into the exhaust to warm up your cats every time you cold start it, which will cause them to plug very quickly as well as poor fuel economy as the heat energy issn't being used to move the car.

\Which cat did you remove? Odds are if your main cat or pre cats were clogged, the same is true on the others.

Also be sure to do oil changes significantly more often. When you engine is cold started, the piston rings have extra blow by gasses. This lasts about 2 minutes of driving. That contaminates the oil with carbon, water, gasoline, and other nasties. The water, when it doesn't get a chance to be boiled off from your oil, creates nitric acid. That nitric acid will eat away the surface layer of all your bearings, crankshaft, camshaft, valves, your seals, etc. Synthetic oil will help with the corrosion, but still. If you're doing 6 1.5 mile drives per day, 5 days per week, thats only 45 miles per week, so by mileage, you could go 2 years some would say (if you only drove to work). The reality is, the contaminants are far higher, and you probably see the occasional drive where the car fully warms up, so maybe do an oil change every 3 months/1000 miles instead. Also look into running 0w-20 oil if it's just seeing those short drives below 30c outside. If you plan to ever run it hard though, or go on a long highway drive (couple hours), put in some 5w-30 instead before you do it. Don't do the 1.5 mile drives on 5w-30 though, as it'll wear bearings quickly compared to 0w-20 just like the 0w-20 will cause high wear used in hot/hard use conditions.

Something with a tiny motor would probably be much happier with what you're doing as it'll warm up faster, but overall, engines just aren't made for being used the way you do it. There will always be sacrifices in lifespan, fuel economy, and added maintenance when you only do short drives.
 

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For a commute like that, you just need an electric car, or a plug in hybrid that can drive purely on the battery for your daily 3 mile both ways commute
 

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Discussion Starter · #4 ·
Yes, expect short city drives like that to have awful fuel economy, as the engine has to add extra fuel to run properly when cold (standard across all gas engines). It's also retarding ignition timing to send extra heat and fuel into the exhaust to warm up your cats every time you cold start it, which will cause them to plug very quickly as well as poor fuel economy as the heat energy issn't being used to move the car.

\Which cat did you remove? Odds are if your main cat or pre cats were clogged, the same is true on the others.

Also be sure to do oil changes significantly more often. When you engine is cold started, the piston rings have extra blow by gasses. This lasts about 2 minutes of driving. That contaminates the oil with carbon, water, gasoline, and other nasties. The water, when it doesn't get a chance to be boiled off from your oil, creates nitric acid. That nitric acid will eat away the surface layer of all your bearings, crankshaft, camshaft, valves, your seals, etc. Synthetic oil will help with the corrosion, but still. If you're doing 6 1.5 mile drives per day, 5 days per week, thats only 45 miles per week, so by mileage, you could go 2 years some would say (if you only drove to work). The reality is, the contaminants are far higher, and you probably see the occasional drive where the car fully warms up, so maybe do an oil change every 3 months/1000 miles instead. Also look into running 0w-20 oil if it's just seeing those short drives below 30c outside. If you plan to ever run it hard though, or go on a long highway drive (couple hours), put in some 5w-30 instead before you do it. Don't do the 1.5 mile drives on 5w-30 though, as it'll wear bearings quickly compared to 0w-20 just like the 0w-20 will cause high wear used in hot/hard use conditions.

Something with a tiny motor would probably be much happier with what you're doing as it'll warm up faster, but overall, engines just aren't made for being used the way you do it. There will always be sacrifices in lifespan, fuel economy, and added maintenance when you only do short drives.
yeah it was the main cat that was clogged, they also say the pre cat is useless now..

I have to say this is my first car and i don't really know about this stuff and since this car has been drived for 133900 miles, i used a 25w-50 high kilometer oil (some one on the autoparts store told me to use)..

So I'm think of switching oil again, so ..let's say i'm driving right now about 45 miles per week, but since my wife is going to sell some cosmetics stuff and i'm going to deliver them, i asume that i will drive about 10-20 (maybe more) miles more than usual

then should i switch to 0w-20 as you suggets?

I have to say in this city is usually 18c(65F) outside in the morning, and 30c (86F) or even above in the afternoon,so yeah it's a bit hot outside in the afternoon ..
thank
 

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Discussion Starter · #5 ·
For a commute like that, you just need an electric car, or a plug in hybrid that can drive purely on the battery for your daily 3 mile both ways commute
Sadly in this country having a electric/hybrid car is a bit outside of our wallets, even mechanics run away when they see your electric/hybrid engine..lol
 

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Basically Stock
2009 GS Turbo. 2007 GT
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5w-20 will be fine your you then.

25w-50 should never be considered for your uses, I wouldn't even use it at the racetrack. High mileage oil causes seals to swell. It's a last ditch effort to lessen oil leaks on old engines. If yours doesn't leak, don't run it, or it'll lessen the lifespan rather than improve.
 
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