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Matz
10-11-2005, 05:27 AM
Hey guys,

My new Evo runs great, but drinks like a fish. Yesterday, I drove 30 miles to work, and my gauge dropped from 3/4 to 1/2. Today, I drove another 30 miles and it dropped from 1/2 to between 1/2 and 1/4. I think I also smell some fumes, but am unsure where they are coming from. If I open up the hood, I don't smell anything at all.

I probably should have driven the car for a little while right after I got it before swapping parts. So far, I've only swapped throttle bodies, and I reused the TB gasket (new one is coming in on Thursday or Friday).

I'm going to be at WORKS today, so maybe they can take a quick look at it, but if any of you have ideas, please let me know. As far as the fumes go, I know that Tam changed his spark plugs and his smelly problem disappeared, so I may check the plugs today as well.

Evo442
10-11-2005, 06:52 AM
Hey guys,

My new Evo runs great, but drinks like a fish. Yesterday, I drove 30 miles to work, and my gauge dropped from 3/4 to 1/2. Today, I drove another 30 miles and it dropped from 1/2 to between 1/2 and 1/4. I think I also smell some fumes, but am unsure where they are coming from. If I open up the hood, I don't smell anything at all.

I probably should have driven the car for a little while right after I got it before swapping parts. So far, I've only swapped throttle bodies, and I reused the TB gasket (new one is coming in on Thursday or Friday).

I'm going to be at WORKS today, so maybe they can take a quick look at it, but if any of you have ideas, please let me know. As far as the fumes go, I know that Tam changed his spark plugs and his smelly problem disappeared, so I may check the plugs today as well.

Souns normal to me! Ha Ha.

Actually, whats your driving style like? My evo has a full exhaust, reflash, cams etc, but my wife can still get 24-26 mpg on highway driving, just like when it was new. Me, I get as low as 4-5mpg at the track. Daily driving I range from 14-18mpg. Point is that mileage varies greatly with how you drive.

Do you run it up to 7000 rpm between shifts? etc etc. Our cars are very thirsty when on boost. Try keeping it off boost as much as you can and I'll bet your mileage gets a ton better. FWIW, my low fuel light generally goes on around 175 miles.

Matz
10-11-2005, 07:02 AM
Thanks for your input! I am driving *exactly* the way I did before. I don't accelerate hard, it's all freeway mileage, and I only go speed limit. I was averaging 26mpg with my old Evo... with the new one, probably about 14. Ouch.

I shouldn't jump the gun on this, and maybe should just drain this tank, fill up again, and then see what happens. The fumes bother me, though, and may be part of the reason for the fuel economy problem.

earlyapex
10-11-2005, 10:02 AM
You might have messed something up with the throttle body switch a roo.

It kinda sounds like your car is stuck in the cold start phase. Which would kick your ass gas wise. Did you hook everything back up correctly for sure? I would triple check everything.

Does your idle settle down once the car is warmed up?



As far as the fumes go, I know that Tam changed his spark plugs and his smelly problem disappeared, so I may check the plugs today as well.

It wasn't his plugs, his evap canistor was disconnected.

wrx2evo8
10-11-2005, 10:41 AM
Thanks for your input! I am driving *exactly* the way I did before. I don't accelerate hard, it's all freeway mileage, and I only go speed limit. I was averaging 26mpg with my old Evo... with the new one, probably about 14. Ouch.

I shouldn't jump the gun on this, and maybe should just drain this tank, fill up again, and then see what happens. The fumes bother me, though, and may be part of the reason for the fuel economy problem.

not to be a dick.. but why did you get an evo and mod it in the first place if you're not going to "drive" it?

Matz
10-11-2005, 03:05 PM
not to be a dick.. but why did you get an evo and mod it in the first place if you're not going to "drive" it?

reasonable question for sure. I bought it to drive hard at the track, not on the public roads.

Matz
10-11-2005, 03:07 PM
You might have messed something up with the throttle body switch a roo.

It kinda sounds like your car is stuck in the cold start phase. Which would kick your ass gas wise. Did you hook everything back up correctly for sure? I would triple check everything.

Does your idle settle down once the car is warmed up?


Good question about the idle, I'll check that! I wonder what I could have possibly screwed up... the TB installation is pretty easy, except for those damn hose clamps. I hooked up the vacuum hoses right, and the two electrical connections only go on one way! The TPS has to be working right, or the car wouldn't drive right at all, but the other sensor, I'm not so sure about.

warpspeed
10-11-2005, 03:25 PM
You have to remember too that when you change the TB you will use a little more fuel. With a bigger TB, more air is coming in and the ECU will add more fuel to get the right mixture.

Matz
10-11-2005, 03:55 PM
You have to remember too that when you change the TB you will use a little more fuel. With a bigger TB, more air is coming in and the ECU will add more fuel to get the right mixture.

I'm comparing fuel economy with my previous Evo, that had the exact same throttle body in it, though.

zyounker
10-11-2005, 04:16 PM
If you smell raw fuel.. Find the source.. Check around the fuel rail.. the lines.. The injectors & grommets...

You shouldnt be smelling raw fuel.

Matz
10-11-2005, 04:47 PM
If you smell raw fuel.. Find the source.. Check around the fuel rail.. the lines.. The injectors & grommets...

You shouldnt be smelling raw fuel.

Yeah, I don't really think it's raw fuel... I smelled around the fuel rail, lines, etc., and it seemed fine.

Matz
10-12-2005, 06:38 AM
I wonder if my fuel gauge is just funky and I'm being paranoid. Yesterday, it was on E, but when I filled up, only 11.6 gallons went in. And after I drove in this morning, the needle moved very little, which was great because two days ago the 30 mile drive dropped the gauge by 1/4 tank. :shock:

Evo442
10-12-2005, 06:49 AM
Maybe you should track your mileage and not watch the guage so much.

Matz
10-12-2005, 08:07 AM
me == paranoid

Yes, I'll do this for the next couple of tanks instead of jumping to conclusions.

earlyapex, FYI, the idle does drop after the car warms up. cold = 1500rpm, warm = 900 (though I thought my old evo idled at 700rpm).

chrisw
10-12-2005, 08:27 AM
Maybe you should track your mileage and not watch the guage so much.

agreed.

Track the millage from a full tank...

earlyapex
10-12-2005, 10:21 AM
earlyapex, FYI, the idle does drop after the car warms up. cold = 1500rpm, warm = 900 (though I thought my old evo idled at 700rpm).

according to my SAFC, warm idle is approx 850rpms

Matz
10-12-2005, 08:49 PM
according to my SAFC, warm idle is approx 850rpms

okie, thanks!

MitsuMan
10-13-2005, 07:38 PM
yea Closed loop idle is around there but its never an exact number.......If you top off your tank you will risk saturating the evap canister with liquid fuel. once this happens it will never be the same and you'll need to replace it if you smell fuel from it. I used to drive 30 mi each way from Gilroy to SJ and used a 1/4 tank round trip.

I always laugh when I see people topping off, for one thing the tank is designed for fuel to expand so if you topp off(over fill) you take up that space and then when you drive the evap with sometimes pull fuel into the canister from the tank and you never get to burn it for power, also the gas pump retreives vapor from the tank everytime you pull the trigger so your not really getting all the gas you pay for .

Matz
10-13-2005, 08:31 PM
I apparently jump to conclusions. I filled up, and so far I've gone 110 miles on just over 1/4 tank.

earlyapex
10-13-2005, 08:46 PM
I apparently jump to conclusions. I filled up, and so far I've gone 110 miles on just over 1/4 tank.

wow! I get about 110 to half a tank. :(

I usually get about 220 or so before it hits E, but no light.

Although I think bouncing off the rev limiter 2-3x a day doesn't help with the mileage. http://forums.offtopic.com/images/smilies/eek4.gif http://forums.offtopic.com/images/smilies/gaysex.gif

Matz
10-13-2005, 09:11 PM
Although I think bouncing off the rev limiter 2-3x a day doesn't help with the mileage.

I shift at 2500 - 3000 rpm. :D I save the redlining for the track, or for the occasional moment where I can't resist blasting onto the freeway.

AreSTG
10-14-2005, 04:14 AM
lol no matter how i drive i dont see more than 250(that was on a highway)

i get like 210-220 before i fill up(no gas light)

EFIxMR
10-15-2005, 10:50 PM
the best i ever got was 265 miles on 1 tank. since i put the aem in i've only been getting 225.

on evom some people claim 300+ miles per tank. either cali gas is just shitty or people are telling a tall tale.

Matz
10-15-2005, 10:56 PM
the best i ever got was 265 miles on 1 tank. since i put the aem in i've only been getting 225.

on evom some people claim 300+ miles per tank. either cali gas is just shitty or people are telling a tall tale.

Well, I've gotten 300 miles on a tank on both of my Evos, but remember that I drive like Miss Daisy's in the back seat. If I open it up on the freeway, my mileage goes way down. Since the Evo is my daily driver, I don't ever drive fast or hard when I'm going to work.

Evo mattVI
10-30-2005, 05:26 PM
It could be one of many things :wink:

The fuel senders on the evo's fuel gauge have never been any good it tends to give false readings all the time.

Plus if you have done engine work and haven’t changed the ecu the standard one doesn’t take well to engine modifications.

Over fuelling is common with the evo ecu as someone said earlier it's idea of sorting things out is to just put more fuel in so you don't get detonation within the engine, plus it really make the car stink and use loads of fuel

My own car is only doing about 190 miles to a full tank and that’s taking it steady, on track it has been known to do a little as 60 mile to a full tank or 3 laps of the Nurburg ring :lol:

Not good when fuel over here is at a all time high of £1 I think that works out about 1.77 in US :?

missred
10-30-2005, 05:28 PM
:lol:Wow I'll take a $1.77 a gallon any day.

Evo mattVI
10-30-2005, 05:35 PM
:lol:Wow I'll take a $1.77 a gallon any day.

Tip never use a currency calculator :lol: :lol: :lol:

ZK
10-30-2005, 10:14 PM
:lol:Wow I'll take a $1.77 a gallon any day.

I think its $1.77 per liter.

Matz
10-30-2005, 11:02 PM
:lol:Wow I'll take a $1.77 a gallon any day.

I think its $1.77 per liter.

That sounds more like it. I have a friend in Manchester who says he's paying $6/gallon! ouch.

FYI, here's a tip for conversions -- you can use google, like

"google gallon in liter" (if you're using firefox)

works pretty well!

Evo mattVI
10-31-2005, 03:47 AM
:lol:Wow I'll take a $1.77 a gallon any day.

I think its $1.77 per liter.

That sounds more like it. I have a friend in Manchester who says he's paying $6/gallon! ouch.

FYI, here's a tip for conversions -- you can use google, like

"google gallon in liter" (if you're using firefox)

works pretty well!

Thanks i will have a look :wink:

DaveLC2
12-04-2005, 09:43 AM
:lol:Wow I'll take a $1.77 a gallon any day.

I think its $1.77 per liter.

Ouch! 3.8 litres in a gal. Using a currency converter for a ball park estimate that's like $6.58 per Gal :shock: At least you have higher octane.

Dave