frost6

Hey I have a a stock b16 em1 with only a cold air intake that's been lowered modestly, flush to the top of the stock si wheels.

I've done basic maintenance as soon as I bought the car;

- checked and replenished all fluids required
- alignment checked, new wheels and treads
- sparks, wires, fuel filter, cap and rotor
- engine additive (forgot the brand name but it was recommended by one of my mechanic buddies)
- consistent 94 chevron fuel (techron concentrate not available in Canada, if there is anyone in bc want to let me know where I can find that stuff in concentrate?)
- check engine light IS on, code P0420, cat below threshold, is currently in the works, however would this affect mpg if it is emissions related? (my province no longer requires emissions testing)

This car is city driven, non-vtec'd, consistent 3500 rpm gear changes and no harsh acceleration. I am consistently filling up for 37 liters(9.77gal) and driving roughly 350km(217 miles).

Are these numbers ideal for this car or is there anything else I can do maintenance wise to squeeze the most mpg out of it?

Bently_Coop

I would check or have your ignition timing checked and also figure out what is wrong with the catalytic converter. If you cat is plugged it can rob mileage from you. 22 mpg seems kind of low, I would think 25+ should be average for a B16.

purgat0ry

iTrader: (3)

I got 29mpg average with mine, mixed city/highway, something is definitely off.
Check to make sure you actually have an O2 sensor and your catalytic is functioning properly (or that you have one of those as well...)

frost6

I have checked my o2 sensors, not voltage wise but they are there and they aren't throwing off a code either but I've posted here before if they can go bad without throwing a code, specifically the primary one, is there anyway I can test it? The o2 sensors look pretty caked on and are in a very difficult spot for me to change on the fly without taking down the exhaust and heating it up or using a breaker bar...

tony_2018

city driven will always yield low mpg, thats because of the stop and go traffic

frost6

Yeah I figured that's the reason for the low number, the car is entirely city driven, just making sure if there's anything else mechanical other than the cat or basic maintenance that would help.

purgat0ry

iTrader: (3)

Your right, but I never got 22mpg with mine even when driving it like an *******.

tony_2018

It depends but the 22mpg is about right since I'm sure we're all pumpin that corn juice, bout 10% here in every station. There was a gas station in Chalmette, La that had pure gas. octane 91. I pumped it and on my way home to Austin, Tx my mpg jumped like a ****. I mean granted I'm in eco mode with the d15z7 but dude I went all the way to Beaumont, Tx and had half a tank. I usually get 1/4 of a tank when I get there.

tony_2018

For me, every oil change I dump in chevron fuel system cleaner, I've made it religious that I ensure my spark plugs are replace on time, same goes with my ignition system. Air filter is replace after 3 oil changes or depends on how dirty it is. I don't wait until **** breaks down, I get to it.

Before I had a b20/b16 combo my mpg was about what you were getting.

frost6

Any suggestions other than changing the cat?

frost6

I've tried to avoid those little known gas stations and always fill up at a chevron using only thier most premium octane because of the supposed techron additive they mix with thier fuel since that stuff is no available in concentrate where I live. also in my province chevron 94 is supposed to be pure gas with only techron, no ethanol.

tony_2018

tire pressure is key

frost6

Checked that a few times, brand new rubber and oem si wheels, filled to manufactured specs (I think 33 psi if I'm not mistaken or somewhere around that) wheels and rubber are in good order, no sign of premature wear due to lowering the car either.

eghatch9295

iTrader: (1)

overfill a bit for increased gas mileage.

tony_2018

When i had my em1, I always had them at 35psi. On my honda civic with skinny tires, I go 40psi, thats dangerous no doubt but my mpg has increase. I just don't drive stupid and start taking corners at 60mph.

frost6

What do you specifically change in the ignition system?

tony_2018

spark plug, wires, coil, igniter, rotor cap(with gasket). Check ignition timing while I'm at it.

B serious

iTrader: (1)

Poor MPG is most often linked to driving habits. Driving habits have a huge impact on MPG.

OP...short trips? Do you let the car "warm up"?

Beyond that....
A cat that is below threshold won't necessarily reduce MPG. But...the cause of the cat being below threshold may be that the car is constantly running rich for some reason.

22MPG is on the low side for suburban driving with a stock EM1. For straight up city driving, that's probably close to normal. Not many people actually do city driving, though. Unless you're a cabbie in Chicago or NYC or you commute in LA, you probably only dabble in city driving. Most city folk don't drive...unless they're driving to/from the burbs.

There's people who comment in every thread with unrealistic things like "my EM1 gets 29mpg uphill, across Manhattan, in the rain with no shoes on, and it has respect for its elders too!". Who cares? This isn't directed at anyone here, btw, before we all get offended.

frost6

I do let the car warm up slightly (not until full operating temperature, but just about once the rpm drops to around 1k.

Beyond that the car is entirly city driven, literally from the east side of the city to the west, vice versa total trip is probably 25km round trip which is around 15 miles. I do live in vancouver which is hilly and mountainous so that could also be a reason for the low mpg as well, I would rate my driving habit as non aggressive simply because there are a **** ton of speed traps along my route because of school zones which doesn't really let me "stretch the cars legs" so to speak.

B serious

iTrader: (1)

The low temps this time of the year in Vancouver are...what? 50's? 40's? (Farenheit)

There's really no reason to let the car idle at all unless it's well below freezing. Even in the shitdepth of winter, I might give the car 1min max. Like...if its -10 F or colder, maybe 2 mins...and that's ridiculously long.

How long does it take you to go 15 miles?

frost6

Yeah I don't idle ridiculously, just about 10-15 seconds does it, I usually do it just based on the idle rpms and not the actual temperature, takes me half an hour to get through my morning drive.

B serious

iTrader: (1)

15 miles. Half hour. Thats a 30mph average. Thats not city driving. Thats solid suburban driving. If you wanted to go 15 miles in a crowded city thru traffic, it would likely take an hour or more. Even if you are driving through a city, a 30mph average isn't sitting in bumper-to-bumper traffic. A 30mph average describes a mix of "highway" style driving and "city" style driving.

You're doing it right by not warming up the car. Get in. Wait 10 seconds. Drive conservatively until the car comes up to temp. When the car comes up to temp, drive normally.

Forget 3500RPM. Shift when it feels right to shift. Anywhere between 3500-7000 RPM is my normal shift point in a B16 car, when accelerating. FWIW, when I had an EM1, I would average 30mph on my way to work, and that netted me like 26-27 MPG normally, and I think those are realistic numbers....if you need some bench mark. Everyone's mileage is different. But I would bet that 80-90% of people fall into the 25-27 mpg average just driving around town.

Beyond that, just make sure the car is properly maintained. Use a good 5W30 oil. Use NGK/Denso spark plugs and O2 sensors.

22 is a bit low for your type of driving. Even with hills.

purgat0ry

iTrader: (3)

This guys got it right.
When did you do a full tune up last?
Filters (air, oil, fuel), ignition parts (Rotor, cap, wires, plugs), etc.

frost6

Not even 10k kms yet, did it very recently.

Obviously your definition of city versus highway is much different then mine. now vancouver isn't no NYC or LA, but for Canadian standards, this is a full fledged city. The route does not take me anywhere near a highway, and is through 100% residential areas of the city, right in the middle of it.

As far as warming it up, I judge it based on the rpms and do drive very conservatively (hence the 3500 gear shifts) but am very slow to pull out because of that reason alone.

tony_2018

Like i said, it varies. There is no EXACT mpg given. All are estimate mpgs for city/highway so there is room for error. Don't be like that fat lady who was trying to sue Honda for incorrectly giving mpg's on there hybrid car.