Car is thirsty!!

[Python]

Hi celica lovers, i hope to get help here from you
month ago i bought celica 7gen JDM, but i think it drinks to much fuel for 1.8l engine, on a full tank 55liters i can drive only about 400km - normal drive to work and back and sometimes to shopping centre (not really racing).

Some information about the car:
Toyota Celica VVTL-I with TRD exhaust.
year: 2000 with 101000km on a clock.
ECU - stock, not modifyed at all.
all the car is prity much stock.

Thing is , when i start my car i can feel slight gas smell, when engine gets warm this smell is gone, car is idling perfectly, drives perfectly, pulls perfectly, lift is amazing. But fuel consumption is bigger than on a 3liter bimmer.

i did simple diagnostic as i thought it was oxygen sensor problem - diagnostic didnt show me anything, no error codes at all, so i thought it didnt see my car or something, so i pulled sensors plug off and drove like that for a few minutes. Connected diagnostic and it showed me straight away that i have problem with sensor, it means sensor is fine. Just to make sure, i brought my car to Toyota specialist, who connected dialers diagnostic bigboy and also measured cars CO with some device he sticked to the rear end of my celica - No problems or any errors, he told me car is perfectly fine and he dont understand what im doing here, took my 20 euros and sayd goodbye. So i went to a local garage and asked guys to jack my car up so i can expect underneath, turned engine on, i find no leaks or smell underneath at all, fuel lines are nice and shiny as new, no damage what so ever. Also looked under the hood, no smels or leaks there. Also took my rear seats out to get fuel pump connections inspected, they are happy, no leaking.

so... car drives well, no error codes, car smells when you start it up, car mpg is to low!!

you have any ideas???

[02GTS_MP]

What type of fuel do you use? I know if I put anything but premium in my car it drinks it like water.

[Python]

well im located in ireland, here they have 95unleaded

[02GTS_MP]

Hmmm, I don't believe our unleaded is 95...wanna say its like 80something. I haven't been home in 8 months so I can't remember. Possible that could be the issue. Someone with more knowledge then me would have to chime in. My only guess the quality of fuel. I know I ran out of gas next to a run down gas station and put $20 in cheap unleaded, half a tank, and got about 70 miles out of it.

[dllang777]

Had to do some conversions. 55Liter = 14.5 gal. 400 Km = 248 miles. you are getting about 4.2 KPL ( 17 MPG). there is definitely something wrong here. How is your air filter? Spark plugs, oil, in other words, go through a tune up check. Driving habits and conditions should not make that much difference. My 02 GT 5 speed is getting 31 MPG, and I do not drive conservative (its my D.D.) and my drive is mixed between highway and stop and go. That's also using regular gas (sorry I haven't looked at the octane rating).

[Koolsilver]

You should try cleaning your MAF. That probably won't fix you problem completely but it's a good start and will help a little. Also in California our gas is rated 87,89,91 and we are told to use 91 in our GTS.

[Python]

our 95 unleaded in US would be 90,25octane


2morrow i will look at vacum hoses, actualy before i noticed that there is one tiny hose disconected from somewhere around air filter box, maybe it causing the problem









P.S iwould love to live in California btw...

[2KGTS]

Check the air filter, replace it if necessary. Clean the MAF with MAF cleaner. 17mpg???? REALLY? That's beyond awful.

If everyone insists it's not leaking it, and it's not present in the exhaust, then it's running hellaciously inefficiently. If my conversion's correct, you're at roughly 62,000 miles. O2 and catalytic converter should be running fine. I wonder what 95 in Ireland translates to in the U.S. Are you putting the proper oil in the crankcase and the transmission?

[Python]

Originally Posted by 2KGTS

Check the air filter, replace it if necessary. Clean the MAF with MAF cleaner. 17mpg???? REALLY? That's beyond awful.

If everyone insists it's not leaking it, and it's not present in the exhaust, then it's running hellaciously inefficiently. If my conversion's correct, you're at roughly 62,000 miles. O2 and catalytic converter should be running fine. I wonder what 95 in Ireland translates to in the U.S. Are you putting the proper oil in the crankcase and the transmission?

yep, did proper CO check and it was fine, so catalytic and O2 sensor are ok, i plan to change transmission oil when i get time (in may probably) Engine oil was changed by previous owner, and it looks nice and clean to. Im still woried about gas smell, my thought was that my O2 sensor was failing so i got bad mixture which didnt burn completely and ended up in my exhaust system, but CO check showed me that exhaust system was fine.

[iand4403]

Sticking brake calliper?

[Python]

Originally Posted by iand4403

Sticking brake calliper?

nope, definitelyt not this

[Soo__Fuego]

At 80,000 miles my sister's Celica drank more gas than a truck. New plugs and a front O2 sensors fixed it. Car had no CEL either btw.

[Python]

MAF clean, air filter new, spark plugs nice and clean, but on 50 liters i can do 410km

[2KGTS]

The dragging brake pad makes sense, but you said that's not the problem. Meaning, you can drive down a highway for 10 minutes, pull over, and none of the wheels (not tires) are not hot to the touch?

Also, I've heard more than once from someone who had their oil changed and noticed drastic drop in gas mileage. They found out the wrong (very heavy) oil was used and replacing it with the proper oil fixed their mileage.

I'd also still want a very close look at those O2 sensors and their operation. The fact that they show no codes and that pulling them gives a code while plugging them back in removes the code doesn't mean they're truly operating properly. I'm no O2 sensor expert, but I know they can be slow to adjust, etc. without blowing error codes. There are better ways to test the sensors but I'm not sure what tools to use, sorry.

If you get the smell of gas at start-up but it goes away. I wonder, then, if you're running really rich until the cat gets heated up. You say you had a CO2 test, but was that on a hot engine and cat?

Have we got a good O2 sensor/cat converter geek on here that can talk about these possibilities? Maybe my impressions are wrong, but I don't think so.

This is an odd one! Keep us posted!

[Python]

Originally Posted by 2KGTS

The dragging brake pad makes sense, but you said that's not the problem. Meaning, you can drive down a highway for 10 minutes, pull over, and none of the wheels (not tires) are not hot to the touch?

Also, I've heard more than once from someone who had their oil changed and noticed drastic drop in gas mileage. They found out the wrong (very heavy) oil was used and replacing it with the proper oil fixed their mileage.

I'd also still want a very close look at those O2 sensors and their operation. The fact that they show no codes and that pulling them gives a code while plugging them back in removes the code doesn't mean they're truly operating properly. I'm no O2 sensor expert, but I know they can be slow to adjust, etc. without blowing error codes. There are better ways to test the sensors but I'm not sure what tools to use, sorry.

If you get the smell of gas at start-up but it goes away. I wonder, then, if you're running really rich until the cat gets heated up. You say you had a CO2 test, but was that on a hot engine and cat?

Have we got a good O2 sensor/cat converter geek on here that can talk about these possibilities? Maybe my impressions are wrong, but I don't think so.

This is an odd one! Keep us posted!

CO testwasdonewith special tool it was tested on a hot engine, idling and at 3000 rpm, failing o2 sensor usualy mess up CO test result, it didnt happen. My car has bytheway only one O2 sensor precat one.
Brakes are not sticky.
What i find today was... when ex owner was replacing air filter he connected vacum (or whatever) hoses on an air box wrong way....the hose that makes butterfly close was disconected, but that hoes that goes under airbox and must be connected under butterfly (with this blue colour thing) was connected to the place where butterfly hose suposed to be, i reconected them back as it supose to be, to early to tell did it affected my mpg. It drove my attention as i spoted disconected hose.


p.s. when engine is cold rpm cutout is around 7000rpm, when engine is hot it goes to 9000rpm.
today after swaping vacum hoses i had 4 bars on a fuel gage i drove almost 60km and lost 3 bars, so dont know any numbers yet...

[bbedward]

How about a bad wheel bearing or cv axle, that can cause drag too.

Sent from my SPH-D710 using Tapatalk

[Newcelica000]

a lot of us drive without the butterfly valve so i bet it woudn't affect your mpg by much...

[Python]

Originally Posted by Newcelica000

a lot of us drive without the butterfly valve so i bet it woudn't affect your mpg by much...

thing is not in buterrfly, the pipe going from intake manifold was connected to the air box, so engine was sucking from itself, im not sure it affect mpg, but i think it wasnt right,

somebody could explain how this vacum system works and what does the hose that goes from intake manifold to the lower part of air box where is electrical connector.

[bbedward]

Originally Posted by Python

thing is not in buterrfly, the pipe going from intake manifold was connected to the air box, so engine was sucking from itself, im not sure it affect mpg, but i think it wasnt right,

somebody could explain how this vacum system works and what does the hose that goes from intake manifold to the lower part of air box where is electrical connector.

I'm not sure what it's called, but the piece with the blue connector has a vacuum line that connects to the intake manifold.

^^ it's eliminated with custom air intakes, and you need to cap off the manifold with an 1/8" cap or so.

Take a picture of the vacuum lines, normally if you have a vacuum leak you'll throw a code pretty quickly due to running lean/rich.

[Python]

Originally Posted by bbedward

I'm not sure what it's called, but the piece with the blue connector has a vacuum line that connects to the intake manifold.

^^ it's eliminated with custom air intakes, and you need to cap off the manifold with an 1/8" cap or so.

Take a picture of the vacuum lines, normally if you have a vacuum leak you'll throw a code pretty quickly due to running lean/rich.

ex owner did a mess and connected this hose to air box upper part!!, i reconected as it should be, drive a little and let you know did it fix my problem

[Python]

it did fix my problem, consumption is now around 11l with heavy foot

[dllang777]

Congratulations Python, welcome to the fun world of Celi's!