Mandystc

Hey all. My names Maranda and I'm a first time Scion owner. Got a small question that's irking me bout my tC. I'm mechanically knowledgeable so i hope yall can help me with this. My tC is way too hard on gas. it can burn a 1/4 tank of gas and only have gone 60-70 miles. i just changed the plugs in it so i know that cant be it. the motor is completely stock. My Cavalier had a 2.4L in it and was nowhere as hard on gas. but the tC is running rich. We figured if it was an O2 sensor it would've thrown a CEL any input on this would be great cuz if it is really that hard on gas i wont be keeping this car. thanx

Vlad1024

Calculate the gas mileage so that we can determine if it's normal or not. The gas gauge is not known for accuracy.

Vindiesel075

before i boosted mine i got about 32 mpg highway....Step off the throttle girl!

Mandystc

I dont get in on it. thats just puttn around at 45/55 mph. the window sticker on the car which was n the owners manual said 27 mpg. i figured it up to be 405 miles per tank. im only 300/350 some. would it matter if im not running the iridium plugs like it calls for? didnt notice that til after i changed them.

emrules2001

That's about what I'm getting. Next time you fill up, write down your mileage. When you fill up again after that, write down that mileage, and take note of gallons pumped. Subtract mileage and divide by gallons to give you MPG. Now that I'm boosted, I generally run about 24MPG, before that, I was around 26-27 on average, just to give you a point of reference.

draxcaliber

What is your Scion's year and mileage? Might be due for a tune up. could be lots of things from air filter, MAF sensor, O2 sensor, proper tire inflation, alignment. whether or not you're using the A/C and so on.

Mandystc

Its a 2006 and has roughly 88000 mi on her. we just got it the last weekend of may so that was the last tune up. we checkd tire pressure and its normal. and just changed the plugs. but it still runs rich cuz u can smell it real good from behind the car. we have been using the a/c a lot lately tho cuz were still havn that heat wave here in virginia

my06tc

iTrader: (2)

did you clean the maf sensor attached to the intake,or injectors could be dirty

Mandystc

I could run some fuel injector cleaner through it. havent tried that yet but have ran octane boost through it. im guessing the maf sensor is good cuz we tried puttn a shorty intake on it with jus that tube with the sensor and a shorty filter and it ran like complete ___! lol.

cmcpride

iTrader: (3)

the best approach would be to remove your maf sensor and clean both filaments check tire pressure, remove negative terminal and wait a minute this will remove all learning values that ecm has learned. reconnect negative terminal fill up tank and last check your mpg...

my06tc

iTrader: (2)

i actually had a bad maf sensor that made my car run rich,i had to buy a new one....but remeber what ever you change or fixed,reset the ecu for like 20 mins at least to clear any bad signals thats stored in the ecu memory and start fresh...with the neg terminal disconnected,then reconnect turn car on and let it idle for at least another 10 mins,this is just from my experience

carben100

iTrader: (2)

Put in a bottle of fuel injector cleaner and clean the MAF sensor for starters. Disconnect the battery for a few minutes after you clean the MAF sensor, and then let the car idle for 5-10 minutes after you reconnect it. You may also want to clean the throttle body and replace the air filter while you're at it.

The spark plugs you installed will work the same as the iridium plugs (assuming they are gapped properly) but will need to be replaced sooner.

Im2c0oL

iTrader: (1)

mine is at 77, my average mpg is 24.5 around 280-300mpt for mix city/hwy! i did seafoam, new ngk iridum, cleaned maf sensor & intake filter. but doesn't make any different, only thing i didn't do is cleaner the throttle body... if you're within 24-26mpg then you're good. if you're looking for higher mpg only a straight hwy road trip will give you the right hwy mpg.

usafscion

iTrader: (4)

Cean the mag, change air filter... For the rest of the crew. Do we have a fuel filter?

jimmyjun

Fuel filter is in-tank.

1. clean MAF
2. change air intake filter
3. use oem spark plugs (iridium)
4. change oil & oil filter
5. use premium gasoline( its known that premium gas lasts longer than regular gas & gives better performance)

i bet if you do those things, your car will improve performance and mpg's.

thendawg

iTrader: (2)

Yeah - the only fuel filter on our car stock is a sock on the pump intank. Its actually not hard to change, but I believe its supposed to be a lifetime filter.

As for your issue, here's what I'd do.

I would definitely clean the MAF sensor, and also remove and clean up the throttle body. Ive seen alot of stock tc's end up with alot of oil/sludge buildup on the throttle body due to the crankcase ventilation system. You can use the aerosol based maf sensor cleaner on the MAF, but Ive typically just used Aerosol brake parts cleaner on the Maf, throttle body, and many other engine parts that are hard to clean, it cuts the dirt/grease/oil very well and won't harm anything.

I'd also recommend using a can of BG 44K Power Enhancer - its one of the best fuel system cleaners on the market IMHO.

Mandystc

Alritey. i really appreciate yalls input. im glad this forum is as active as it is. anywho i will clean the maf sensor and trottle body, prob run a can of seafoam thru it. it just had a tunep up not long ago, just changd the plugs and oil was changed about 2-3 weeks ago. it still has the stock breather box but my fiance took the air filter out. (why idk. i guess cuz he wantd to hear the intake. lol) we already run midgrade gas cuz ours is the same price as regular where we get our gas. so when i get some time i will try cleaning those parts and if it still burns get a can of seafoam. i'll let yall know what happens after that. thanx a lot to everyone!

draxcaliber

if you're running the a/c a lot (i'm in MD, i understand how insane the heatwave is/was), then it helps to decrease the amount of the sun light entering the car to make the a/c's job easier.

first off, when running the a/c, have the shades for the sun roof shut, this helps decrease the sun light heating up the interior of the car. tinting the windows helps too. and not all window tint is created equal, some cut UV more than others etc. check local laws and so on.

Vindiesel075

350 is all i get really before turboing....and thats all highways well mostly

Mandystc

ok, so i guess it sounds about right. but thats kinda lame for such a large 4 cylinder. but anyway i do plan on tinting my windows here soon. couldnt decide how dark but i think im doing 20% all around. now just gotta buy the stuff. ;)