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Discussion Starter · #1 ·
ok i have noticed that lately my car has been getting horrible gas mileage!! Today i was sitting in my car when i got home from class and the mpg meter on the screen was like counting down every 4 seconds give or take. I used to average around 19 with screwing around hear and there but now its like 14 which is rediculous!!! :x The price of gas is going way up hear and my mpg gallon in going way down boy does it suck... Any one no what the problem could be. I just installed my 3" dp no cat within the last few weeks which i think is proably contributing if not causing the problem but 13-14mpg? If i still had an exhaust leak like i encountered when i first put it on would that do it? Because i know on n/a cars if you have a leak you get horrible gas mileage....
Please help spending way to much on gas.... :oops: :(
Nick P.
 

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HNNLIC
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Try clearing out your MPG meter on the SID. Also when was the last time you changed your plugs and air filter? Those things may have something to do with it.

I too used to get about 14 mpg, but then I reset my ECU, and added other parts, and now its back to average around 18 and 24 MPG. My highest was 40MPG right after I changed my plugs, and drove back to Iowa from Kansas.
 

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Discussion Starter · #3 ·
ced i tried clearing the sid but it like imeadiatly drops very low again... how often do u need to change spark plugs the car only has 21k on it.. Also i have an itg intake with one of those foam filter im not sure about cleaning it?
 

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HNNLIC
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Well on the spark plugs, I know people that change them out every other oil change lol. I would change them though....it couldn't hurt...only help.

As far as the filter...just take a look at it. If it looks pretty durty...get a K&N recharge kit, or soak it in soapy water, and let it air dry.
 

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Discussion Starter · #5 ·
man i hope thats it because it cost me way to much for gas with it being $1.85 at the lowest for regular and up to $2.10 for 93octane...
If anyone has any other suggestions let me know
 

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HNNLIC
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Try reseting that ECU yours first. Of course you'll need to have your radio code ahead of time.
 

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Discussion Starter · #7 ·
how do i reset the ecu and were do i get the radio code.... if i set the ecu could it cause my cel light to come on now.
are u sure that if there was a leak or having no cat it wouldnt effect mpg
 

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HNNLIC
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Disconnect the negative battery cable for about 15 min. Radio code, you get from a dealership.

Im not sure of the CEL light. I think it was going to come on at all, it would've by now.

Of course the leak and not having a cat causes MPG changes (as do all upgrades). But like i said my MPG went up. But I have a different year than you, so its up to you.

As far as resetting the ECU...its not really a big deal to me because it would happen if your battery ever died, or you switched it out. But its all up to you and how comfortable you are with doing it.

Of course you could always wait for a second opinion. 8)
 

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The Dealership or SAAB would have the code for your radio ....just give them your VIN number.

Don't use the regular fuel in a modified or turbo car....caused my CEL light to come on, and the fuel mileage sucked until I ran her dry, and refueled on Sunoco 94 Octane or Shell hi octane. I also avoid putting too many fuel additives in her....seems to affect the O2 sensors at times, even though most additives claim not to.

The 3 inch downpipe makes that turbo spin up quicker, and the ECU needs to relearn the car so it will take a while unless you reset the ECU like suggested by disconnecting the battery or pulling the appropriate fuse on your car.

You mentioned that there's no cat... Most American made SAABs have two O2 sensors. The sensors need to sense a change in oxygen levels as it relates to the fuel mixture being burned. In essense the cat is just a big filter that cleans the exhaust gases. The rear O2 sensor (after the cat) compares exhaust gases to the front O2 sensor and uses +/- .5 volts to signal the ECU the mixture is burning rich or lean. When there is no difference then you get a CEL lamp light.

You can fool the system by adding the appropriate resistor on the O2 sensor to provide the adjusted voltage levels needed to fool the system. Too complicated to get into. In other words .... you should probably add the race cat...unless your state requires no smog checks.

If your trying to avoid having to put your radio code back in again....I think there's a way to pull an ECU related fuse on your generation of SAAB without pulling power to the radio....can't remember. But if not, the dealership is only a phone call away if you need your radio code, and didn't cost me a dime when I had to re-enter the code on mine.

hope this helps a little....

regards
 

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one word - MAM! Check it for gunk - mine was cleaned and it began to get better milage - and the other day I had it really cleaned - I'm back to 20mpg around town even with a few floorings here and there. And that's with a car with now almost 276,000 miles!! I get about 28hwy - but it does go up the longer the ride - best so far was 54mpg hwy 8) It's all in how you drive, the octain you run and how good all your lines are. OH - and transmission fluid also helps to have in the case :lol: Good things to check anyways. I was getting piss poor mileage when my trans was EMPTY - and yes - still drove OK with nothing in it :lol: :p
 

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i have a tendancy to get like 16-18 for normal driving, like to school and back, but i jump of the highway for like 12 miles, once or twice a month, and i can get it up to 22 or so
but i tend to drive hard between my house and school, so that kills the gas mileage

I think a K&N will help me much

Brian
 

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ive had the same problem....i mean i definatly drive the car really hard but still the sid tells me in gettin around 13.9 mpg which is horrible. i cant image i drive that hard. i havnt made any long highway stenmts recently so i dunno if my highway mpg is still around normal.
 

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Wow, i'm feeling really good about my steady 26mpg in the CSE now, my dad regularly gets 32+ in his 9-3, but he just drives around an island. I wish i had something to add beside some self congratulation, but that's all i got.
 
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