R-Spec Very Rich @ WOT

[JeffGST]

Another experiment:

At half tank (of the 20% E85/80% 91 Octane mixture) I decided to add more E85 to the tank in small increments and then observe closed and open loop engine operation. The motor ran perfectly up until I added 1 full additional gallon of E85. Closed loop operation began to show some very slight hesitation at the 2200-3000 RPM range during part throttle. But WOT performance is through the roof! Not only is the leaner full throttle AFR's increasing performance, but the additional octane from the Ethanol is probably adding more timing advance. I don't have any sort of datalogs to prove this. I wish I had software available to view and modify the stock tables.

Previous mixture 20% E85 + 80% 91 Octane
Half Tank = 2 Gallons of E85 + 8 Gallons 91 Octane
New mixture = 3 Gallons of E85 (27%) + 8 Gallons 91 Octane (73%)

Afterwards, I added 2 more gallons of 91 Octane, and the part throttle performance is back to normal. From my experiment, I will not fill more than 5 gallons of E85 to a full tank of 91 octane. Even though full throttle performance increased at a higher E85%, I don't want to sacrifice idle and part throttle, since that where I drive the car 99% of the time.

I don't recommend anyone to do this. I'm just describing what I'm doing to my 5.0L to lean out the full throttle top end and decrease black soot on my bumper.

 

[amartz]

Go to your dealer because cloud of black smoke under acceleration is not normal!

If it's the first time in a while that you've stomped on it, it's very normal, for any manufacturer. If it does it every time, and never changes or clears up, well, that's a different story.

 

[amartz]

Any time the driver applies more than half throttle, the ECU goes into Open Loop operation and it ignores the O2 Sensor.

I wouldn't have guessed half throttle. I thought it had to be more like WOT.....

 

[JeffGST]

I wouldn't have guessed half throttle. I thought it had to be more like WOT.....

If you've ever driven a car with a Wideband O2 sensor, it is obvious when open loop begins. Idle and cruising is the only time you see 14.7 ratios. Anytime you are half throttle and above, you are dipping into the 12's and much lower AFRs. This is where you lose all your MPG at.

With a datalogger it's even easier. The Front O2 in closed loop will constantly oscillate from 0V to 1.0V at idle and very light throttle. Once you give it some throttle, it stops moving in open loop and becomes a steady line anywhere from 0.80V to 1.00V depending on how rich the mixture is, with the higher voltage meaning richer.

 

[amartz]

If you've ever driven a car with a Wideband O2 sensor, it is obvious when open loop begins.

You assume a lot. Actually, I have. It was a 98 Jeep Wrangler, with a stroker in-line 6. It took 3/4 throttle or better to see the a/f ratio drop to 12. And I think it would take similar throttle input with the 3.8 to get it out of closed-loop mode. My opinion.

 

[JeffGST]

You assume a lot. Actually, I have. It was a 98 Jeep Wrangler, with a stroker in-line 6. It took 3/4 throttle or better to see the a/f ratio drop to 12. And I think it would take similar throttle input with the 3.8 to get it out of closed-loop mode. My opinion.

I don't know what you read in my post, but I never assumed you didn't.

The absolute tell tale sign of Open loop mode is the non-oscillating Front O2 signal as I stated before. I'll have to get a datalog from a OBDII scanner and find out exactly when and where the ECU goes to Open Loop.

 

[Turboba6]

I've run about 6 or so 1/4 mile passes with my Low mile 2013 Equus, and Every Pass is pretty much 14.00@101.00mph, now mph is the Important number of course, and that is at a Weight of 4700Lbs with me in it ( I weight 160), so I'll Add 2 gallons of e85 to a Half tank, allow it to Mix well, and make a few more passes, as THAT is the Only Real world test, short of a Wheel Dyno....

 

[PMCErnie]

You drink mixers are entertaining, but I still maintain that if your pipes are smoking regularly, ya got an engine problem. See the dealer!

 

[JeffGST]

You drink mixers are entertaining, but I still maintain that if your pipes are smoking regularly, ya got an engine problem. See the dealer!

This is how that will go if I ever take it in.

Customer: My Genesis seems to smoke a lot when I get on the throttle

Dealer Underwriter : That seems normal to have black smoke, but we will have the guys take a look at it.

1 hour later

Dealer Underwriter : Our techs took a look and found no engine codes or anything out of the ordinary with the motor. Everything is fine.

They will blame the 115F weather or the fact that I drive my car 2000 feet above sea level, when the real reason for all the black smoke is the overly rich programed fuel map in these cars. This probably affects the drivers that are at higher elevation than those closer to sea level due to the air density thinning out.

 

[qstarweb]

This is how that will go if I ever take it in.

Smoking is not healthy we all know that.

Dean

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[svensk]

Every GDI car I've seen does this under WOT. My turbo sonata ran pig rich.

 

[Tonfinnhead]

To revive a dead post. I've been running 6 gallons of e85 to 14 gallons of 93. I a data log daily. Timing has since gone up from a Max of 24° up to 27 and sometimes even 28° I've seen on my logs. The engine definitely makes adjustments with the e85 blend. I've also picked up mph in the quarter mile from 106 to 109-111 depending on my launch (traction is a huge issue). Part throttle the O2 sensors take care of you. I watch closely as the fuel trim adjust with the e85 and it adds the fuel to equal what the factory requires. Wot you are ok because you need 30% more fuel for e85 wot and Hyundai has this thing running super rich. Under wot I get a blip of black smoke and she's screaming away.