Why am I getting 11 mpgs?

2114 Views 21 Replies 11 Participants Last post by 03SonicBoom, Oct 27, 2009

asiansensation78

Discussion Starter · Oct 27, 2009

So like the title said, I get some terrible gas mileage. I have an o/r x pipe and the version of the diablosport predator before they removed the option for you to turn off the rear O2's. I followed all the instructions on the manual to have the O2's turned off and have the "Predator Tune" loaded in my car. I first thought it was because of my right foot, but I drove the car lightly on a tank and still only went 160 miles before I was on empty

What's going on here?

It's warm and humid in Miami so I have the A/C on most of the time, and we have a bit of traffic. I also have 4.10's, but do no highway driving. The Predator Tune just says "Use premium fuel" and I put 93 into it.

Could my front O2's be bad? It's not throwing a code...

1 - 20 of 22 Posts

HMUSN

· #2 · Oct 27, 2009

I'm going to call it the tune.

11mpg is horrid even with an off road pipe.

asiansensation78

Discussion Starter · #3 · Oct 27, 2009

Wait do o/r pipes decrease mileage by nature?

And does anyone know how I can turn off the o2's if I update my predator?

HMUSN

· #4 · Oct 27, 2009

yea they do.. and it should be in the options menu once you update.

Don't quote me on that.. I am an SCT guy.

suprajay79

· #5 · Oct 27, 2009

<---saw an increase of .5 mpg with his O/R H...

+1 for tune. Anything below 19 is unacceptable for me.

suprajay79

· #6 · Oct 27, 2009

BTW, welcome back, HMUSN...long time no see!

:welcome

energiesource

· #7 · Oct 27, 2009

consider yourself lucky, i get like... 9 mpg

suprajay79

· #8 · Oct 27, 2009

energiesource said:
consider yourself lucky, i get like... 9 mpg

Dude, I would get rid of my car in a heartbeat if I got that! LOL!

I'm really easy on it, too...I don't drive too aggressive and I shift real nice. I keep it quiet and smooth and usually come out to about 20-22 mpg around town and 24-26 on the interstate (depends on cruising speed too).

energiesource

· #9 · Oct 27, 2009

well i need a tune bad from the cams, but still. lol i shouldnt be getting 9 mpg. its what, a 60 Litre tank, and i get 250 km's per tank... so thats like 24 l/100 kms, which works out to 9.68 mpg lol.

drazga97

· #10 · Oct 27, 2009

energiesource said:
consider yourself lucky, i get like... 9 mpg

i get about 9mpg or less

suprajay79

· #11 · Oct 27, 2009

Holy ****...

Either way, we've all settled on Asiansensation should be getting more than just 11 mpg. Energie, you're the exception, Mr. "I've got cams, na-na-na-na-na"!

Just playin. But Asian, you might want to get with a tuner close by who can help you out with your problem. He/She would be able to pinpoint where you're sucking so much fuel down and correct it accordingly. Even if you have an older-style tuner, you can still play with them (I don't know about Diablo, but I know SCT has software updates...maybe check into that?) and figure out where your fuel gremlin lies.

energiesource

· #12 · Oct 27, 2009

haha, i didnt sign up for 9 mpg when i bought the cams

thats like an extra monthly fee on top of what i already paid for them. it needs a tune bad, the a/f ratio is probably through the roof. if my ****ing tuner would have fit me in before the winter i wouldnt have had this problem

ajm

· #13 · Oct 27, 2009 (Edited)

Do you have any mods that absolutely require you to use the tune/tuner? Or can you set the car back to the factory tune? If you can do so put the factory tune back on it for a few days and see how that works out for you. If thats not an option check out what the fuel trims are doing by viewing the live data.

Any obvious signs of running rich? Whens the last time you changed the fuel filter, and if never how many miles are on the car. Sounds odd but its a starting point.

suprajay79

· #14 · Oct 27, 2009

Haha yeah I suppose there is a bit of a fee for a sweet-ass lope and a nice gain in power...

What cams, btw?

suprajay79

· #15 · Oct 27, 2009

ajm said:
check out what the fuel trims are doing by viewing the live data.

That's why I suggested he go to someone about it. I have no clue how to do this.

energiesource

· #16 · Oct 27, 2009

uh probably just cams? i have headers, o/r h pipe, slp exhaust, an intake, and the cams, and thats about it for power. the tuner i bought had a few preprogrammed on there for the mods i had except cams, but i dont know how well that worked.
the cams were from modular speed. theyre some XPS 2v ones.

Catfiesh

· #17 · Oct 27, 2009

energiesource said:
consider yourself lucky, i get like... 9 mpg

gahh. thats terrible.. I get a min of 16 in the cobra.. see 22 on the highway

asiansensation78

Discussion Starter · #18 · Oct 27, 2009

Glad to hear it's the tune and not some mechanical failure lol

Spark plugs, fuel filter, air filter, etc have all been changed in the past 4 months. Car has about 60,000 miles on her. After my next fill up I'll use 87 and put the tune back to factory and see what I get. I'd like to update my predator too, I've heard the new canned tunes are better than what I have. They offer the update for free online but I really don't want to lose the ability to turn off the o2's for my midpipe.

Mathos1

· #19 · Oct 27, 2009

It could be the o2's, mine did the same thing when they made a custom xpipe for it, o2's are still there but no cats, and no tune or o2's off. Could be running rich.

M.P. Cobra Fan

· #20 · Oct 27, 2009

That is crazy. I don't have an O/R midpipe, but even with my SCT tune and 4.10's I get 19-21 in the city and 22-23 on the highway. I would park my car if it got the kind of mileage you get.

1 - 20 of 22 Posts

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