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General Information => General => Topic started by: JGVWDiesel on June 08, 2010, 11:04:25 am

Title: Mileage 1.6 NA
Post by: JGVWDiesel on June 08, 2010, 11:04:25 am
Hey all, I'm just going to ask if this is reasonable mileage given my conditions. I'm getting about 35 mpg in the city (I only drive city right now) and I go up several very large grade hills everyday as well as having to go down them. I have a lot of stop and go because all the lights, as well. The engine is a 1.6 NA with 363k on it with what seems to be original injectors and pump. It smokes a fair bit above 75%ish throttle. All the wheels spin pretty freely when lifted, so they're not an issue. The biggest and longest hill I have to climb is a 10% grade over just under 2 kilometers. There's a couple more small ones between 7 - 10% as well.

Just wanted to see what others thought about my mileage given what I have to drive each day.
Title: Re: Mileage 1.6 NA
Post by: Wayland on June 08, 2010, 02:02:23 pm
That seems really low to me. I'm assuming your mpg figures are calculated using imperial gallons, not US? My Jetta still got 53mpg, albeit mostly highway when the injectors were really bad.
Title: Re: Mileage 1.6 NA
Post by: JGVWDiesel on June 08, 2010, 06:34:07 pm
No I was using US MPG. In imperial MPG I'm getting 42.2 MPG. Are most people using imperial on here or something?
Title: Re: Mileage 1.6 NA
Post by: Wayland on June 08, 2010, 07:37:45 pm
I live in Canada, so I use imperial gallons. I assumed that since you also live in Canada, you would too.
Title: Re: Mileage 1.6 NA
Post by: rabbitman on June 08, 2010, 07:38:07 pm
No I was using US MPG. In imperial MPG I'm getting 42.2 MPG. Are most people using imperial on here or something?

AFAIK US mpg is used most.

I'd say that's a bit low, what year/car is this? If it's a mk1 style then the odometer is known to slip and miss about a .1mi per mile causing it to show lower mpg than you're really getting.
Title: Re: Mileage 1.6 NA
Post by: JGVWDiesel on June 08, 2010, 08:20:08 pm
86' american built golf 1.6 NA. The speedo does tend to bounce around a bit in the lower speeds, if that can count for much.
Title: Re: Mileage 1.6 NA
Post by: clbanman on June 09, 2010, 01:06:06 pm
91 Golf 1.6 NA 5spd.  I have averaged 46.64 mpg (Imp) or 5.81 l/100km since Sept. 2009  (7550 km).    514,000 km, only modification that I know about is 2.25" exhaust.  Not sure which tranny I have but it is geared much lower than my 86 Golf and gets about 200 km per tank less.    I beat on it a fair bit which makes a difference too.
Title: Re: Mileage 1.6 NA
Post by: burn_your_money on June 09, 2010, 06:43:16 pm
I was getting around 5.4-5.2l/100kms in my mk2 NA. That was about 50/50 highway/city.

When you drive do you keep the RPMs up or put it in the tallest gear you can without lugging it?
Title: Re: Mileage 1.6 NA
Post by: JGVWDiesel on June 09, 2010, 09:14:39 pm
i try to hit the tallest gears I can without having to lug it around. i'm also a heavy guy and I'm also usually with my gf as well.
Title: Re: Mileage 1.6 NA
Post by: 8v-of-fury on June 09, 2010, 11:21:37 pm
I can still hit ridiculous numbers with a fully loaded car (four people and our stuff in the trunk... packed full, have to sit on the trunk to close).. I usually try and keep it up there around what feels like 30-3500 rpm if I need any power, but if not its the tallest gear.
Title: Re: Mileage 1.6 NA
Post by: JGVWDiesel on June 10, 2010, 08:46:14 am
Its also hard to tell but it SEEMs like I get a slight bit more grunt with the cold advance lever pulled out. You can definetely hear the difference when it's cold but its harder when warm. I wonder if that means my inj pump should be advanced some??
Title: Re: Mileage 1.6 NA
Post by: 8v-of-fury on June 10, 2010, 08:51:29 am
A little more advance is never a bad thing, especially if your still sitting at stock numbers. I have my n/a timed to 1.03mm
Title: Re: Mileage 1.6 NA
Post by: burn_your_money on June 10, 2010, 09:16:32 am
Since you are mainly in town try and keep the RPMs one gear higher (if it sounds realistic) for a tank and see if that effects your mileage any.
Title: Re: Mileage 1.6 NA
Post by: JGVWDiesel on June 10, 2010, 10:32:21 am
Ok, I'll be coming up to my next tank in a bit here. ( really odd going over 2 weeks on a tank, im not used to it haha.)

One thing I'm curious about with these kind of fuel injection systems is do they cut fuel in decel like a efi gas engine does or something else? I tend to use my engine braking just about every hill I get to, could this be adversely affecting my mileage?

Next tank I want to try to introduce a few different things to my driving style to see how it changes it.

Also, what size would my fuel tank be if it's an american built 86 diesel golf?
Title: Re: Mileage 1.6 NA
Post by: JGVWDiesel on June 10, 2010, 10:33:30 am
i often forget this, but thanks for all your guys help so far. it's kind of odd that i'm driving to get the most fuel as I can where as before in my previous vehicle I was tuning it to get the most power out of it as I could but was getting a pathetic 17 mpg :P
Title: Re: Mileage 1.6 NA
Post by: 8v-of-fury on June 10, 2010, 01:22:25 pm
i believe you have a 50-55L tank iirc. The mk1's (pre-85) have a 40L

it is odd going a long time on one tank eh? I found this odd when i switched over to diesel as well.

Fueling is based on the pedal from what i have read.. You need to push the pedal for the governor to pull the flyweights over to start injecting fuel. I would think with no pedal input it is merely injecting the bare minimum per cylinder to sustain combustion at that rpm.
Title: Re: Mileage 1.6 NA
Post by: burn_your_money on June 10, 2010, 02:13:23 pm
In conditions where the vehicle is driving the engine the pump is not injecting any fuel.
Title: Re: Mileage 1.6 NA
Post by: JGVWDiesel on June 10, 2010, 03:16:28 pm
50-55l? is there a specific? it would be nice to know for when I fill up before emptying the tank to tell how much I have left for reference.

it is odd for sure.

ok, cool. so I guess using engine braking isn't really an issue then.
Title: Re: Mileage 1.6 NA
Post by: rabbitman on June 10, 2010, 03:23:18 pm
In conditions where the vehicle is driving the engine the pump is not injecting any fuel.

My tach is run by transducer clamped onto the injector pipe and when I coast above about 3000rpm the tach quits reading. If it's much below that it'll still read.
Title: Re: Mileage 1.6 NA
Post by: JGVWDiesel on June 11, 2010, 11:07:20 am
interesting. how hard was that to do?

can anyone chime in as to what the exact tank size is? thanks!
Title: Re: Mileage 1.6 NA
Post by: JGVWDiesel on June 11, 2010, 01:33:18 pm
I forgot to mention, I also have power steering. (which seems to be leak at the reservoir, but even with good amount of fluid it still squeels on first starts.)