CO2 tester: for Air/Fuel mixture

[biglang_liko]

Thanks Sir Niky, the car I'm refering to is a genesis coupe 2.0 turbo. The reason I'm asking about air fuel ratios is to make sense of the results of a mileage experiment I did to determine which is the best fuel to use since the manual is pretty vague on that (all it says is the car can run on 87ron and is e10 compatible).*

Using pure gasoline Blaze 95 octane, I averaged about 7kms per liter. Using petron super unleaded e10 93 Ron *I averaged around 6.5 kpl. *

What's puzzling me is when I used xcs e10 95 Ron, which I was expecting to register a mileage reading somewhere between the two previous fuels, my mileage actually dropped to below 6kpl!

And even stranger is the oil level on my dipstick showed a small increase in level (both cold and warm readings), possibly indicating fuel contamination in the oil which i read could be a result of *running too rich. I'm pretty sure it's not coolant getting into the oil as there's no indication of coolant loss. The engine runs fine with no knock on all three fuels so I assume the ecu is doing it's job making all the necessary adjustment automatically. *

If it is excess fuel bleeding into the oil as a result of an overly rich AFR, that would definitely account for the drop in mileage using e10 95ron.*

I also assume the ecu is programmed to run the engine in the most efficient way possible.

MY QUESTION IS: why would the ecu run an overly rich mixture on e10 95 ron and not on e10 93ron and pure gas 95 ron? If anyone would care to speculate. TIA**


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[BJ71]

Forget the emissions center, take your car to a performance shop with a wideband. Most emissions centers only have readouts for HC, CO and particulate emissions. While you might be able to tell if the car is running incredibly rich from the HC readings, you won't have the tuneability you'll get with an O2 sensor.

Yes, a modern five-gas analyzer will do O2 also... but local emissions centers are only required to measure HC and CO. Nobody does NOx or O2 testing at the smoke places.

Hi sir niky, What performance shop do you recommend here in manila?

[bambino]

Thanks Sir Niky, the car I'm refering to is a genesis coupe 2.0 turbo. The reason I'm asking about air fuel ratios is to make sense of the results of a mileage experiment I did to determine which is the best fuel to use since the manual is pretty vague on that (all it says is the car can run on 87ron and is e10 compatible).*

Using pure gasoline Blaze 95 octane, I averaged about 7kms per liter. Using petron super unleaded e10 93 Ron *I averaged around 6.5 kpl. *

What's puzzling me is when I used xcs e10 95 Ron, which I was expecting to register a mileage reading somewhere between the two previous fuels, my mileage actually dropped to below 6kpl!

And even stranger is the oil level on my dipstick showed a small increase in level (both cold and warm readings), possibly indicating fuel contamination in the oil which i read could be a result of *running too rich. I'm pretty sure it's not coolant getting into the oil as there's no indication of coolant loss. The engine runs fine with no knock on all three fuels so I assume the ecu is doing it's job making all the necessary adjustment automatically. *

If it is excess fuel bleeding into the oil as a result of an overly rich AFR, that would definitely account for the drop in mileage using e10 95ron.*

I also assume the ecu is programmed to run the engine in the most efficient way possible.

MY QUESTION IS: why would the ecu run an overly rich mixture on e10 95 ron and not on e10 93ron and pure gas 95 ron? If anyone would care to speculate. TIA**


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check the fuel trim ,and see what it says.

[niky]

Some of the big performance shops will have a wideband and a dyno (Autoplus, Speedlab, Autotechnika), and will be able to perform diagnostics on the car. Retuning AF, however, will require the ability to hack the stock ECU (Autotechnika and Orange have this... Orange does it for Subies only, though... I think) or a piggyback controller.

This all depends on what you want to do with the car and what modifications you have on it (knowing what your car is will help).

MY QUESTION IS: why would the ecu run an overly rich mixture on e10 95 ron and not on e10 93ron and pure gas 95 ron? If anyone would care to speculate. TIA**


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Because RON is only half the story.

Local gas labels are all over the place. Performance on differing gasolines for engines that require higher octane will vary widely.

Your manual states 87... but that's AKI, a US measure. One that's roughly equivalent to 92-93 RON, but not exactly. But if it runs without "tope", then it's safe.

If it runs more economically on Blaze, then your ECU self-adjusts to higher grades of gasoline. Here's the rub. Blaze may be "only" 96 compared to XCS's "95", but it's got better additives. Blaze and V-Power actually do perform better than similar 95-97 RON gasolines. On the dyno, the previous formulation of V-Power was better than Blaze. Don't know about the reformulated one, but it's the high octane gas my tuned engine is happiest with. (with my aggressively advanced timing, V-Power gives me the smoothest running at cold start-up)

As for oil dilution... if you're running even slightly rich, yes, the alcohol content of the gasoline can actually dilute the oil as it washes down the cylinder. You'll have to observe over time whether the oil level still goes up and if it looks like it's changing color.

E10 is a royal pain in the ass.

[biglang_liko]

*Bambino - Sir, the casa said all computer readings are normal, but I'm kinda concerned with the black soot thats coming out of my tailpipe. I wipe it clean every morning but when I get home in the afternnon, meron nanaman. So I suspect the car is running too rich even if the engine analyzer says all readings are normal. I also get the feeling na parang walang alam yung casa after they put in the wrong viscosity of oil kaya hindi rin ako masyado nagtitiwala sa sinasabi nila



*Niky - Sir, here's a picture of my oil which is only two weeks old, its supposed to be fully synthetic Elf 5W-40, according to the casa. Dati nasa "dot" lang yung oil level, now its upto the "F". Medyo madumi nga ang itsura for two-weeks palang na gamit. Hindi kaya nagkamali-mali ang settings ng ECU sa pagpalit-palit ko ng fuel? I read na pwede i manually reset ang ECU by pulling the battery to return it to its orig settings, malalaman ba ng casa yun if I reset it myself?

[niky]

Most likely the first time you checked the oil hadn't settled. It should be at "F" after an oil change. Just check once a week first thing in the morning and see if the level changes.

Oil doesn't look too bad. You have to understand that many turbocharged engines that don't have direct injection run fairly rich... a short search on the internet shows that the Genesis turbo runs a piggish 12:1 at full throttle... going down to 9:1 at high rpms. (that's even richer than the Evo!) It should run at 14:1 at part-throttle in cruising, but if your engine has learned around bad gasoline, it can throw off those ratios.

Yes, you can reset it by disconnecting the battery. No, it isn't a warranty issue.

One toy you can get to see how your engine is running is the Scangauge II. There are local vendors for this now... it's a plug and play device that can display a number of parameters for your engine, including fuel economy, engine load and open/closed loop operation. For maximum economy, you want to keep it in open loop (at 14.7:1) as often as possible.

http://www.scangauge.com

[biglang_liko]

Thanks very much Sir Niky, your inputs were very helpful in putting my mind at ease. I'll try resetting the ecu when I get a new tankful of ethanol-free gasoline. I only hope Blaze doesn't go e10 too in the future.

That scanguage looks like a great tool to have. I have been planning on getting a boost guage, but this scanguage is way more versatile (I suppose the manifold pressure reading also functions like a boost guage). I'll definitely check it out

[roaman]

sir need hepl pinaayos ko ung sasakyan ko pinalitan ung engine valve pero biglang nasira ung airflow sensor pag kinakabit siya namamatay ung makina pero pag hinde ok siya kaya lang matakaw sa gas lancer glxi 94 po siya please need ungent help-thanks