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Replaced all plugs and coils, still getting 13mpg


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i asked about the tune. he gave a vague reply, but yes who did he tune and how did they not notice something like this?

 

i was also wondering how he was determining mileage? have you actually done the math yourself or just trusting the display? wonder if injectors were replaced with incorrect units to cut costs again. slim chance most likely but something to think about.

 

as far as it goes now, id say find a new tuner and explain in detail your concerns and let them dig into the detail investigations.

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Wouldn't it be funny if it had bigger injectors on it prior and the car was returned back to stock but they never reprogrammed the MPG back to stock?

 

It's got to be something odd like that or you're tune is so bad it's just pissing fuel into the cyl.

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Obviously he just got a cheap MAF so I'd rather replace it with an OEM one.

How much should I expect to pay for one? I'm seeing them anywhere from $170 to $350 which sounds like a little much.

 

It looks like fred beans wants $142, IF 22680AA31A is the correct part number.

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i asked about the tune. he gave a vague reply, but yes who did he tune and how did they not notice something like this?

 

i was also wondering how he was determining mileage? have you actually done the math yourself or just trusting the display? wonder if injectors were replaced with incorrect units to cut costs again. slim chance most likely but something to think about.

 

as far as it goes now, id say find a new tuner and explain in detail your concerns and let them dig into the detail investigations.

 

Right I told them before I got it tuned I was having really bad MPG, it was between 12-14 and yes I did the math, I was watching my fuel consumtion religiously and it was 1 under what the readout was saying so pretty accurate. I just filled up Sunday so I'll wait until the tank is empty to do the number again. I could even watch the gauge drop as I went back and forth to work (just a few miles). I'm going to replace the MAF first and if that doesn't help I'll get a cable.

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I just cleaned my MAF with the CRC MAF cleaner over the weekend and gas mileage went from 17mpg to 19mpg. I think it had salt spray on it from the unrelenting salt they've been dumping on the highways this winter. May want to try cleaning the MAF before tossing it.
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If you change injectors, your MPG display is wrong. It cannot be recalibrated.

 

 

I read today that Cobb very recently released some new software that will allow you to dial in an accurate MPG readout even with bigger injectors when using their ProTuner software.

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It's been about 4-5 years since I re-explored this. But back then, it wasn't possible / worth the effort.

 

5 hours of tunning starting from scratch got the MPG within 2-3mpg, but the tune was crap to get it there so we dumped it and started over without trying to get the MPG to display right.

(Updated 8/22/17)

2005 Outback FMT

Running on Electrons

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It's been insane around Atlanta the last few days, my car held up fine though and was giving people rides yesterday.

 

I've been driving slow. I filled up Sunday, reset my trip meter and I'm at half a tank now, I've gone 80 miles. At 7.5gal in 80 miles is 10.6mpg :(

Gonna order a new MAF tomorrow.

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Try this out mwiener2:

http://www.romraider.com/forum/viewtopic.php?f=34&t=9530

 

i had a pretty noticeable jump in mpg after PCV replacement. but I was nowhere near 13.

 

I'm about to do mine, makes me forgive Subaru for making it so painful if there is such gains...!

05 LGT 16G 14psi 290whp/30mpg (SOLD)

12 OBP Stock 130whp/27mpg@87 Oct

00 G20t GT28r 10psi 250whp/36mpg

22 Ascent STOCK

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Ok, I'll say no.

 

But you are correct, you don't need a tune for it.

 

Next time you want or need tuning, look up my Tuner, Mike Kinsman, of www.tuningalliance.com he's really that good.

 

 

After you install the MAF, if you reset the ECU, which could be a good idea, or just start it and see how it runs.

 

If you reset the ECU, you should drive it after you start it. or at least rev the engine a few times (2000-3000rpm) and let it relearn idle. Driving it is better then not.

305,600miles 5/2012 ej257 short block, 8/2011 installed VF52 turbo, @20.8psi, 280whp, 300ftlbs. (SOLD).  CHECK your oil, these cars use it.

 

Engine Build - Click Here

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Put the new MAF in and gave it a spirited drive around town. The shaking is gone at idle.

I watched the live MPG readout and it seemed to jump around anywhere from 18 to 33 but I'll give it a few days to get a better idea of what my MPGs are now, it seems to be better.

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  • 2 weeks later...

The shaking is back and it says I'm averaging 13MPG.

I'm gonna get a cable and data log it but I see there's some issue with the chipset in the cables, I have 2 saved in my bookmarks

 

[ame=http://www.amazon.com/BestDealUSA-OBD-II-2-409-1-Cable-VAG-COM/dp/B008HO23OC/?tag=vglnkc6475-20]Amazon.com: DHSHOP USB OBD-II-2 KKL 409.1 OBD2 Cable VAG-COM for VW/AUDI: Car Electronics[/ame]

 

and

 

http://www.ebay.ca/itm/USB-KKL-VAGCOM-409-VAG-COM-409-1-USB-Port-Cable-with-FT232BL-Chip-Black-HOT-/221308400341?ssPageName=ADME:L:OC:CA:3160&clk_rvr_id=578106807137

 

Do I need to get the Ebay one over the Amazon one?

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Compression test involves warming the engine up, removing all 4 spark plugs, inserting a compression tester ($50) into one cylinder, press the throttle all the way down, and crank it 5-10 times.

 

See how high that cylinder got, write it down, go to next cylinder rinse repeat.

 

 

Btw I replaced my PCV valve, mine was kind of nasty and stuck a little. Didn't really improve my gas mileage though.

http://images.rvsmods.com/var/albums/Cars/LGT/Engine/General/PCV-Valve/CIMG0486.JPG?m=1391352001

05 LGT 16G 14psi 290whp/30mpg (SOLD)

12 OBP Stock 130whp/27mpg@87 Oct

00 G20t GT28r 10psi 250whp/36mpg

22 Ascent STOCK

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The shaking is back and it says I'm averaging 13MPG.

 

How's your O2 sensor(s)?

 

Mine shakes quite a bit and my mileage is shit, but that's also because my O2 isn't sending a proper signal (Have CEL, though), so I'm sure it's not fueling right. (Read: dumping fuel)

 

I'd seriously consider investing in a Cobb AP if you haven't already. You're clearly gonna dump more money into the car anyway -- You can find 'em used on CL, or new from Cobb for about $650. And having the ability to base tune, plus pull codes and run multiple maps -- it's the best money you can spend on your car.

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Compression test involves warming the engine up, removing all 4 spark plugs, inserting a compression tester ($50) into one cylinder, press the throttle all the way down, and crank it 5-10 times.

 

See how high that cylinder got, write it down, go to next cylinder rinse repeat.

 

 

Btw I replaced my PCV valve, mine was kind of nasty and stuck a little. Didn't really improve my gas mileage though.

http://images.rvsmods.com/var/albums/Cars/LGT/Engine/General/PCV-Valve/CIMG0486.JPG?m=1391352001

 

It shouldn't improve MPG. It might cut down on oil use if stuck.

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