Civic HX Lean Burn "Econo" Light - Page 6 - Fuel Economy, Hypermiling, EcoModding News and Forum

Chrysler kid · 03-25-2015, 07:54 PM

No clue man. My vacuum gauge offers little insight

firehawk618 · 03-25-2015, 10:19 PM

I did confirm it only goes into 16 valve mode under heavy acceleration.

I plugged in my Genisys OTC and monitored the Vtec solenoid.

Sure enough, under heavy load it kicks into 16v mode right around 2800 rpm's.

Under light acceleration it stayed in 12v mode all the way to 5000 rpm's.

For the record the Vtec-E only has a single profile on the cam unlike the D16y8 found in the EX as well as damned near all other Vtec engines.

When Vtec-e engages all it does is lock the other 4 intake valves to the only cam profile there is.

EDIT:

I hooked up a LED to the vtec solenoid and will correct my observations.

16 valve will engage at 2800 under heavy throttle. It will engage at 3100 no matter what including light throttle.

This MAY be the reason you lose LB after 3100 rpm's no matter what.

Chrysler kid · 03-25-2015, 10:59 PM

Hmm odd never thought it did that. The power range in 4 v mode must just be for vtec then

I hooked up my volt meter gauge to the white red wire on connector d for my secondary 02 sensor readings and you were right I can get into lean burn in any gear, in fourth at 45mph it will lean burn

The car also.idles in lean burn aafter the initial injector bump to smooth it from decelerating

I'll have to post a picture of this little volt meter. It is extremely tiny and I think it looks great!

Chrysler kid · 03-26-2015, 12:06 AM

Samsung sucks for night time shots but I am very please with this little volt meter

While the car can lean burn in other gears it is extremely difficult to get it to stay in lean burn. I'm thinking a grille block would help

You almost have to trick the car into lean burn flicking the throttle back and forth

firehawk618 · 03-26-2015, 02:02 AM

Quote:

Originally Posted by Chrysler kid

Hmm odd never thought it did that. The power range in 4 v mode must just be for vtec then

I hooked up my volt meter gauge to the white red wire on connector d for my secondary 02 sensor readings and you were right I can get into lean burn in any gear, in fourth at 45mph it will lean burn

The car also.idles in lean burn aafter the initial injector bump to smooth it from decelerating

I'll have to post a picture of this little volt meter. It is extremely tiny and I think it looks great!

That's great.

When you say it idles in lean burn do you mean decelerating in leanburn?

That is actually DFCO where your fuel injectors shut off under deceleration if your foot is completely off the throttle.

They will kick back in when you touch the throttle or the rpm's dip below 1200.

firehawk618 · 03-26-2015, 02:04 AM

Quote:

Originally Posted by Chrysler kid

Samsung sucks for night time shots but I am very please with this little volt meter

While the car can lean burn in other gears it is extremely difficult to get it to stay in lean burn. I'm thinking a grille block would help

You almost have to trick the car into lean burn flicking the throttle back and forth

Through my testing so far I have found that 2700 rpm's is the sweet spot whether you're in 3rd, 4th or 5th gear in my car.

I have found if it's being stubborn if I floor it then release gradually back to cruise that will normally kick it in if it's in the mood.

Right now I have a very small yellow LED to monitor 16 valve mode and another very small LED as my shift light.

Much better than a full blown light on the cluster face. Easy t o ignore yet there if I want to see it.

Chrysler kid · 03-26-2015, 09:15 AM

Quote:

Originally Posted by firehawk618

That's great.

When you say it idles in lean burn do you mean decelerating in leanburn?

That is actually DFCO where your fuel injectors shut off under deceleration if your foot is completely off the throttle.

They will kick back in when you touch the throttle or the rpm's dip below 1200.

My secondary 02 sensor reads 0 volts at idle when the car is warmed up after a few seconds at idle. Under deceleration in gear it also reads zero, in lean burn readings go to zero and there is a noticeable drop in power

When cold my numbers are very lean about half what they are when the vehicle is warmed up, I can see why the egr was needed for emissions.

In the picture I posTed the car is zero volts at idle, it's highest reading is usually around .6 when accelerating. I verified the voltage readings using a live data function on my obd2 scan tool

At idle when warm the intake has an audible whistle noise as it draws air in through the intake

firehawk618 · 03-26-2015, 07:40 PM

My 2nd o2 reads as high as .85 when really on the throttle and will drop to zero on LB. At idle it averages .125 or so. The only time it's zero on my car is LB or DFCO.

I wired up a main relay cut off switch so I can kill the engine on long down hill runs and coast.

I found a very big negative to this on our HX's. This to the ECU is the same as turning the key off which resets the LB timer.

I am going to instead experiment with killing the +12v feed to the injectors to kill the engine and see if this also resets the LB timer or not. If it does not I will use this method. If it does then I will just deal with it.

Chrysler kid · 03-27-2015, 10:24 AM

Yeah mine reads zero at idle. I am running iridium plugs and a short ram intake

When cruising in neutral the car will read voltage at idle I assume to adjust to the air being forced into the intake from the outside air

firehawk618 · 03-27-2015, 11:37 AM

Quote:

Originally Posted by Chrysler kid

Yeah mine reads zero at idle. I am running iridium plugs and a short ram intake

When cruising in neutral the car will read voltage at idle I assume to adjust to the air being forced into the intake from the outside air

Does your gauge read into the thousanths? If not that's why you see zero.