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propr'one
12-04-2005, 08:54 PM
Ok, my car definatly just drove about 261 KM on a tank of gas. its almost low enough for the light to turn on.

just to make things clear for myself
328's have a 60 litre gas tank and a 5L reserve right?
the last 1/8 of the gas tank (when the light is on) means your tapping the reserve right?

cause im pretty sure last time the light was on i only put about 40 litres in, mabye the gas gauge is wrong. i mean 261/ 40 litres means i get 4 KM per litre, or use 22 litres per 100 K.

NOTE: this particular tank of gas has fuel injector cleaner in it, however my previous tank of gas was also around this efficent, but i didn't set the tach for it.

My cel is on, but im pretty sure its because of an o2 sensor that has already been replaced. Air filter is brand new, car has new 5W30 oil in it, idle is shakey but within reasonable limits.

also when i drive, it seems like i get about 12-13 L per 100KM

(note, 261 was ALL city driving, so its low but not that low)


any advice guys?

im going to go fill up tonight/tomorrow and hope that only 40 litres go in, which would mean my gas gauge is just wrong

Kal
12-04-2005, 09:32 PM
maybe it was a bad tank of gas?
was it 89 octane?
When was the o2 sensor replaced?

T.Dot_E30
12-04-2005, 09:36 PM
Are you sure you replaced the right o2 sensor? I believe u got 2 or 4.

propr'one
12-05-2005, 12:13 AM
ok new tank of gas, put 57 litres of 91 esso (this is the worse crap i use in my car, sunoco was closed)

I still need to get my car scanned to make sure the o2 sensors are all setup properly

thinair
12-05-2005, 12:34 AM
328's have 4 O2 sensors, and that is definately bad mileage.

Sounds like something is making your car run in safe mode or something....does your check engine light work? Will your car pull to redline?

I get at worst 450km/h of mostly city driving, and at best 700km+ of all highway.

And our cars don't really have a reserve, plus that light isn't consistant. It's sort of dynamic, depending on how you've been driving. If you drive hard, the light will come on earlier, if you take it easy the light won't come on for a while. It also depends on average speed too, or so it seems.

SickFinga
12-05-2005, 01:02 AM
328's have 4 O2 sensors, and that is definately bad mileage.

Sounds like something is making your car run in safe mode or something....does your check engine light work? Will your car pull to redline?

I get at worst 450km/h of mostly city driving, and at best 700km+ of all highway.

And our cars don't really have a reserve, plus that light isn't consistant. It's sort of dynamic, depending on how you've been driving. If you drive hard, the light will come on earlier, if you take it easy the light won't come on for a while. It also depends on average speed too, or so it seems.


700km??? I dont believe it
The most I got out of my car was 550 and I never reved over 4k and it was city/highway mix.

Usually I get about 470km on a full tank.

Also light does not come on depending on how you drive, it comes on when you got 8liters left in your tank.

thinair
12-05-2005, 01:09 AM
Ok, I've hit 700 more then just once, we have 65L tanks, our cars do better the 10L/100km, I doubt it's just mine. I live like 5km from the 400, my school is right off the highway, like 1km, there isn't a whole lot of city driving happening, plus when commuting, I generally drive pretty slow, like 95-105km/h. And my fuel mileage has only gone up since I removed a bunch of weight from the back of the car. Also the 0 toe on my front wheels makes a difference (not tire scrubbing), as does properly inflated tires.

How come my gas light will come on when I'm cruising at like 140km/h, then as soon as I slow down to like 80 it'll go off. If I have 1/4 tank, and I cruise at 200km/h for a few minutes, my gauge will drop to completely empty and the light will come on, then when I slow back down to 110km/h I'll be back at 1/4 tank and the light will go off. No corners or braking either, just a smooth transition between speed. If I have the light on for like 15 minutes, and if I turn off the car and turn it back on, the light will be off and sometimes stay off for another half an hour. My e34 is even worse for this. I've put in gas in my car with the light on after driving hard and the car wouldn't take more then 50L, I've also put in 60L with the light only being on for 10-15 minutes.

I'm telling you, it's dynamic. I've filled up more then a few times too, this coming from a guy who consistantly burns though $4000 of gas per year (thanks Quicken for the information)

SickFinga
12-05-2005, 01:19 AM
here is how I know its not dynamic

I have full OBC, I unlocked it so I can access hidden measurements.
One of them, how many liters of gas I got in my gas tank.
I use it all the time, and I noticed that light comes on when it reaches 8 liters.

thinair
12-05-2005, 01:21 AM
I'll let you know if I get the same results once I finally do my OBC conversion. But it's not like I just made up what I posted above.:moon:

Bill Gates
12-05-2005, 02:08 AM
something is definitely wrong.. i average about 525km+ on a tank (little hwy and local driving), pure highway i can easily hit 650-700km. thats using 91+.

Nelson, i noticed that with my low fuel indicator light as well. when my speed sustains a lower speed, it will go off... if it monitors gas consumption per km's, i don't see why it can't be dynamic. hmmm... i'll have to pay closer attention next time.

Bill Gates
12-05-2005, 02:12 AM
700km??? I dont believe it
The most I got out of my car was 550 and I never reved over 4k and it was city/highway mix.

Usually I get about 470km on a full tank.

Also light does not come on depending on how you drive, it comes on when you got 8liters left in your tank.

Sick, strange how you can't hit over 550km on a full tank, it must be all that HP you got under the hood. :D

propr'one
12-05-2005, 02:32 AM
Sweet, now i need to either find rico r or wait for mv325is to get his scanner:D

propr'one
12-05-2005, 03:18 AM
I can hit what i assume to be the rev limiter nelson, im not really sure. Come to toronto and tell me:D

I honestly have no idea which o2 sensor was replaced, my mechanic did it. The CEL works in the sense that its always on. does that mean it works? iunno

anyways please describe what you mean by does the car redline.

(also, more stupid noob questions: If indeed it is the o2 sensor that is ****ed, if i fix it will i get more power? i've had this car for 2 months and its already not enough:D)

Justin e36
12-05-2005, 04:40 AM
bad tank of gas, or that fuel additive you used. either one is the problem, it's happened to me earlier this year. You might need another tank of gas before it is all flushed out of your system. Next tank should be okay. Don't think it's the o2 sensor just yet. Your CHECK ENGINE light does come on when you start the car, right?

propr'one
12-05-2005, 08:11 AM
Yeah CEL's on, but i scanned the car, got the o2 sensor code, drove around for a few days, fixed the o2 sensor, so i was hoping that the problem was fixed and the CEL just needs to be cleared. I guess i'll find out once i scan it again

M3ti Compact
12-05-2005, 08:50 AM
Amateurs! I can make it to Windsor and back on 1 tank averaging 130km/h...that's 800kms- no cruise control, no overdrive, and I did it twice.

rico328i
12-05-2005, 11:35 AM
Whenever you want me to scan your CEL....let me know.

Miguel
12-05-2005, 11:44 AM
I constantly monitor my consumption.

I average 480KM on a full tank with mixed city/highway and 600+ of mostly highway.

Im sure on a full tank of straight highway at 120km/hr I'd get 700ish.

///MP
12-05-2005, 09:43 PM
Amateurs! I can make it to Windsor and back on 1 tank averaging 130km/h...that's 800kms- no cruise control, no overdrive, and I did it twice.

Damn that's good! I know a couple people who also get awesome mileage on their way to Windsor. Is it downhill both ways? With a tailwind? WTF is up with Windsor?!

The best I've ever done is 780km in my old Accord (63L tank, H22 motor, Accord tranny) and 530km in my ///M3 (2L left in the tank!).

MP

thinair
12-05-2005, 10:09 PM
no cruise control, no overdrive, and I did it twice.
No overdrive?? It's not like you have overdrive anyway (assuming it's 5spd)

///MP
12-05-2005, 11:00 PM
No overdrive?? It's not like you have overdrive anyway (assuming it's 5spd)

Are all e36 5th gears 1:1? (Other than the ZF used in the 328/M3, which I already know has direct 5th)

MP

thinair
12-05-2005, 11:07 PM
Yes, both the getrag and ZF 5spd trannies have 1:1 5th gears. Actually most of the ratios are pretty close to each other.

propr'one
12-06-2005, 02:37 AM
Well it must've been a bad tank or something. Drove 129 KM's today, its showing 3/4 full.

I'm staying under like 3500, which is sooooooooo boring

Justin e36
12-06-2005, 06:35 AM
Amateurs! I can make it to Windsor and back on 1 tank averaging 130km/h...that's 800kms- no cruise control, no overdrive, and I did it twice.

That sounds about right.. my 318 does around the same if I speed a bit. The tank will go further if I keep the speed down and am more conscious about throttle position on hilly highways. I go to Kitchener and back to Etobicoke in a night (around 200km) using a tough over 1/8th tank, that includes some speeding, and some conscious driving.

City driving though.. bah.. that's another story.

mech9T8
12-06-2005, 12:15 PM
Just to put in my $0.02, I get 600km on average and 700km with mostly highway driving.

propr'one
12-06-2005, 12:49 PM
well idunno if i can get like 550 out of a tank i'd be thrilled, from your posts it seems that's pretty reasonable

bmdbley'sBro
12-07-2005, 02:59 PM
little thing can eat your gas

things to check:
tire pressure.
clean air/fuel filter

good spark
wheel bearings or dragging brakes, car roll back on hills like it's suppossed to?

cars eat a lot of gas idling aparantly :confused:

///MP
12-07-2005, 07:56 PM
cars eat a lot of gas idling aparantly :confused:

Since you're not moving you consumption is at 0 mpg or infinity L/100km...so it doesn't actually use more gas than when you're moving (in fact it uses less...much less), but in automotive terms it "consumes" the most.


little thing can eat your gas

tire pressure.
clean air/fuel filter

Don't forget M52B32...:D I'm tellin' ya, if I get better than 11L/100km I'm ecstatic!

spooner_dee
12-08-2005, 05:01 PM
on a side note for you proper one and everyone else i would not be running your tanks to anything below 1/4 a tank unless you cant help it.

Running your tank to near empty is a bad thing to do, with the gas being that low your picking up more dirt and sediment thats in your tank into your fuel system and shortening the life of your fuel filter and can even clog injectors over time.

I dont care what gas station you go to or what octane you put in, there is always garbage in the gas that you dont really need getting in your engine. Which also brings up the point that you shouldnt go to any gas station that has a tanker filling at the time, wait a day or so for all the dirt and sediment to sink to the bottom of their tanks so you dont get it in your car.:cool: *th-up*

thinair
12-08-2005, 05:17 PM
Well, that's a bunch of shit. I once removed my truck's gas tank, it was spotless. There was no sedement in it at all. Plus all gas station pumps have pretty large filters that get changed regularly. I know, I used to work at one and change them all the time. Also, on every car I've ever owned I always go down to the last 5 liters, every tank. I've opened up fuel filters for curiosity, the one in my e36 and e34 was spotless, the one for my truck had a few grains of sand in it (because it had a small hole in the filler neck).

bmdbley'sBro
12-08-2005, 05:18 PM
Since you're not moving you consumption is at 0 mpg or infinity L/100km...so it doesn't actually use more gas than when you're moving (in fact it uses less...much less), but in automotive terms it "consumes" the most.


yes i realize the consumption gauge would read nothing.

but i've heard/read this;
in the sense that idling eats more gas in 2,3 mins then
say shutting off the car & restarting it would.

thinair
12-08-2005, 05:27 PM
yes i realize the consumption gauge would read nothing.

but i've heard/read this;
in the sense that idling eats more gas in 2,3 mins then
say shutting off the car & restarting it would.
2-3 minutes? you could turn your car on and off like 6+ times per minute and still use less fuel then it running for the full minute. (Applies to fuel injected cars mostly)

spooner_dee
12-09-2005, 11:13 AM
Well, that's a bunch of shit. I once removed my truck's gas tank, it was spotless. There was no sedement in it at all. Plus all gas station pumps have pretty large filters that get changed regularly. I know, I used to work at one and change them all the time. Also, on every car I've ever owned I always go down to the last 5 liters, every tank. I've opened up fuel filters for curiosity, the one in my e36 and e34 was spotless, the one for my truck had a few grains of sand in it (because it had a small hole in the filler neck).


well consider your self lucky then, maybe canadian gas is cleaner then here in the US. But i still would never run my tank below a quarter.

bmdbley'sBro
12-09-2005, 11:33 AM
actually i thought CDN gas was dirty...
like not refined as much as the U.S ?

I kept hearing/reading ...Highest sulfer content?

nikisil blocks in 530's had trouble with the sulfer or sum crap...


Anyway's sedement or just jellified gas is easy to find on Bikes or stored cars.