Oh well. Best of luck. :) When the GM Goodwrench mechanics can tell you why GM uses hard sensors on 2011 vehicles when they could use VFS, please share the thinking with all of us. Current OS's support both hard and virtual sensing. And agreed, it IS in the software. If GM Goodwrench mechanics can tell you where, that would be great to know. :)Quote:
Originally Posted by samgm2
Which 2011 GM vehicles use a hard fuel composition sensor?
Quote:
Originally Posted by gmh308
If you are in the US you would know them as Pontiac G8. Holden Commodore. V6 and V8 models. Also known as Chevrolet Lumina in Middle East and Sth Africa.Quote:
Originally Posted by samgm2
The G8 was introduced in the US in 2008 and was produced until 2009 (2 years).
In addition, a search of alldata reveals that no fuel composition sensor was used in either year.
The Lumina was discontinue in 2001 in the US.
I have yet to verify the use of a fuel composition sensor after 2002, although I have found references to a couple in 2006. That said, there are inaccurate references in this thread for cars made in 2011.
That means the hard sensor has been gone for AT LEAST seven years in all cars and in most cars for more than a decade. So why would new computers support it?
The use of a hard fuel composition sensor in any vehicle is ill-advised. We should turn our attention to enabling the virtual function in ALL vehicles.
My experiments with E-85 tunes reveals that with proper advance (12-18 degrees), E-85 yields equivalent or superior mileage and power to gasoline.
Estimates of mileage based on combustion energy alone, border on meaningless. Equally important is the reversibility of the reaction. Alcohol burns much slower and is thus much more efficient for converting heat to energy.
There has GOT to be a parameter that turns the virtual composition sensor on.
Once I deal with VATS, I will test a 2009 Flex Fuel E-37 with a non flex fuel 2007 Cobalt. Either it will work or it will not.
If it works, it means that the function is FULLY enabled by software and we just haven't found all the parameters to enable it. If it doesn't, it means that an external signal is missing in the non-flex fuel vehicle.
If it is fully in software, I would guess that there may be a hunting rate parameter or a loop gain(s) parameter(s) that may have zeros in it (for non FFV).
Sam
Chemical/Controls Engineer
Quote:
Originally Posted by gmh308
Sam, don't take this the wrong way, but do some OVERSEAS GM vehicle research.
Check out Holden, Vauxhall and Chevy in other countries. The overseas Lumina is
a re-bagged 04-06 GTO.
-Justin
The 2011 Holden Commodore (G8 basis until Pontiac shut its doors, but coming back as the Chevy Cop Caprice) V6 and V8 flex fuel cars use a hard sensor (IIRC that may be all models for 2011). It can be purchased NOW as a spare at a GM/Holden dealer for the 2011 cars. The information, oddly enough, is accurate.Quote:
Originally Posted by samgm2
Really interested in how you manage to get better mileage out of E85 than gasoline when at stoich its flowing roughly 45% more fuel by weight.
VFS CAN be turned on in GM controllers. EFILive opened this door maybe 2 years back. It just doesnt want to work as it should. Even tried stock FF tunes and VFS wont run. So yes, there is an input missing as you mention that it needs to validate the process and then run the learn cycle. It uses both fuel level and fuel tank pressure to commence the cycle...though now I cant remember for sure whether I ran a simulation as well for the fuel tank pressure. Maybe I didnt. It was about a year back. Must swap the E67 out and put an E38 back in and give it shot again. :)
And as LS1Sleeper pointed out, just because something isnt available in the US, doesnt mean it isnt available somewhere else on the planet where the other 95%+ of the inhabitants of earth hang out. The rest of the world is not the 52nd and 53rd states of the US :), Chevy's are sold in the middle east (Dubai etc...they have cheap gas and a speed crazy... :cool:), south africa, and the car the G8 was derived from is the largest selling car in Australia, and also exported to the UK and Singapore and middle east countries (Chevrolet Luminas), etc, in some forms.
Relax a bit. This isn't a battle. If as a group we are able to find out why the flex fuel function isn't working, this will be good for everyone.
If Efilive can play a significant role in this???...
Or... would we rather continue to supply the middle east with oil dollars while at the same time the NON OPEC countries continue to be bled?
Yes, you can get better mileage from E-85 because the reaction is more reversible. I currently lead a design effort for an engine based on E-85, E-100 and M-100 (Methanol). The efficiency of a pure methanol engine running at high compressions is more than twice that of gasoline!
Yes, the energy content of the fuel is primary in determining mileage. Just as important however are:
1. The reversibility of the reaction.
2. The compression ratio.
The brake efficiency of a gasoline engine (assuming reversible conditions) is only 18%. The brake efficiency of an alcohol engine (at a CR of 20:1) is 48%! This exceeds even diesel which sits at 40%.
Gasoline is lousy fuel. Alcohol is superior in nearly every respect. Methanol trades for about $1.00 per gallon and the US currently produces more than 3.6 Billion gallons per year of it from Natural Gas. This is a fuel we can make rapidly here in the US.
Since I am talking only about code modification in this case and I am not altering the compression ratio. The gain in efficiency is due ONLY to the far more reversible reaction that takes place with Alcohol fuels. So yes, despite the fact that the energy content of E-85, a greater percentage of the energy in E-85 will convert to useful work.
In an Ecotec 2.2 liter engine the following resulted in a dramatic increase in mileage for E-85.
1. High octane spark table copied into low octane spark table.
2. Added additional 8 degrees to low octane spark table.
3. Added 12 degrees to high octane spark table.
Additionally, I have been heading a research effort at my company and have developed an optimized procedure for determining optimal spark. Once completed, I will release the algorithm (and likely, the full program) to the public.
Finally, your logic that at a particular flow rate of air the E-85 required will be 45% more than gasoline is flawed. That assumption presumes the same efficiency. What I am saying is that you will need less air and therefore less E-85 to make the same power because efficiency has increased.
Sam
Chemical Engineer/Research Scientist
Quote:
Originally Posted by gmh308
I would love to give money money to the farmers up in Queensland who produce our E85 fuel as you would like to see your money go to local US farmers, but when the cost price does not out way the additional fuel used what is the point?Quote:
Originally Posted by samgm2
For me, the Australian government stuffed up on the pricing. By my calculations, the extra fuel used on E85 it needs to be priced about 35 - 40 cents per litre cheaper, currently it's only 20.
I think I recall Buick marketing the direct injection turbo 4 in 2012 will get the same fuel economy on regular or E85.
I have been contemplating doing some serious tuning on my car on E85 to try to get the fuel economy better, but I don't 100% understand the ideal calculations on fuel ratios and timing for E85.
Ditto. In Sydney 10c per litre differernce at one station tonight :(. E85 costs more to run that regular ole gasoline.Quote:
Originally Posted by GMPX
:) I guess thats why you were battling the truth bru, and asserting inaccurate information was being stated :rolleyes:.Quote:
Originally Posted by samgm2
Great to hear there is work going on to unleash the efficiency potential of methanol.Quote:
Originally Posted by samgm2
Well if we are talking a regular production engines on E85, vs optimised designs running on methanol which at present are out of reach with very high compression ratios that will also run regular gas, if the engine is running closed loop, at 9.8:1 we are talking 45% more liquid than gasoline at 14.7:1. Yes or no? Approximately that is, give or take a few points of specific gravity differences. Maybe my math is wrong. :)
That said, appreciate your insight into how "reversibility" of the combustion process is applicable to a current and regular production engine. Isnt that getting in to a little Alchemy? :)
I head an automotive engine research division at my company.
The information I've provided is accurate. Moreover, my motives for disseminating it are pure and intended to help move us away from an unsustainable fuel source that continues to be the primary source of income for countries that hate us.
I would like to apologize to my friends from NZ. I had no idea that EFILive was based out of NZ until I ordered it Friday of last week. I had no intention of presenting the US as the only market out there. I simply have little access to the rest of the world in my day to day life and I mean no disrespect. On the contrary, I have always had the highest respect for the people of New Zealand and their respect for the environment.
That said, it is the attacks against alcohol fuels that are inaccurate. Alcohol fuels have yet to realize their potential. The engines being produced by the Auto manufacturers today can best be characterize as "ALCOHOL TOLERANT". Stated simply, they are gasoline engines FIRST and E-85 is simply an afterthought. Tuning PCMs to maximize E-85 efficiency WILL result in dramatic improvement - often exceeding the MPG and power of gasoline.
The book "Energy Victory" by Dr. Robert Zubrin is an excellent source of information regarding alcohol fuels, their potential and the reason we don't have them to any meaningful degree.
Gasoline enjoys a monopoly that is very difficult to break. Auto manufacturers aren't in bed with the oil companies. They ARE the oil companies. It is in their best interest to continue to destroy the efficiency of alcohol as a fuel.
Think of the car as the printer and gasoline as the ink. You can buy a very cheap printer because the inks are going to be a constant source of income for the printer manufacturers.
We will NEVER have a meaningful alternative fuel option if auto manufacturers have their way.
The assertion that gasoline has more energy per volume than alcohol is accurate, but energy content alone is not definitive for work output or determination of MPG.
There are two ways to dramatically increase the efficiency of an engine.
1. Slow the flame front.
2. Increase the compression ratio.
In both cases, alcohol wins. There is simply no competition. An alcohol engine can support compression ratios in excess of 20:1. Try that with gasoline.
As for a slower burn (a more reversible reaction), once again alcohol wins. The gasoline in E-85 actually hurts more than it helps with this. Since often the "gasoline" used in E-85 contains higher ratios of n-Octane to iso-Octane, the resulting octane number can be as low as 94. This is a dramatic reduction in octane number from the 105 or 106 for neat ethanol or methanol.
Gasoline is a pathetic fuel. It simply burns far too quickly.
Keep in mind that it was a waste product produced during distillation of crude oil in 1860 (the product they were after was lamp oil). For 40 years, gasoline would be dumped into the Ohio river. This resulted in the Ohio river becoming the most polluted river on the planet (catching fire 7 times). The perfection of the Otto Cycle by Nicholas Otto made available an engine that could run on a waste product. That made it cheap and desirable. But that doesn't change the fact that gasoline is a bad fuel. The only reason to use it is if it is available cheaply. This is no longer the case. Gasoline is becoming outrageously expensive and wreaking havoc on the economies of NON OPEC countries around the world.
EfiLive, along with other companies of their type and the DIY community is in a unique position to expose the truth regarding alternative fuels. The DIY communities have long been a source of inspiration to large manufacturers as well as a means of keeping them honest regarding what is really possible.
Sam
Research Scientist
Chemical/Controls Engineer
Quote:
Originally Posted by gmh308
Not alchemy but rather, thermodynamics.
I have seen much with regards to the application of Hess's law in determining and comparing potential mileage (a comparison of combustion energy). That said, Hess's law is to thermodynamics what kindergarten is to education. It is a beginning.
Thermodynamics goes far beyond simply comparing combustion energy. For our purposes, it examines reversibility and its effect on converting heat to work. The foundation of thermodynamics as a science begins with the Carnot Cycle. The Carnot Cycle begins by assuming a reversible reaction. You can think of a reversible reaction as one that is infinitely slow (one grain of sand being added on top of the piston at a time).
The faster the reaction, the less efficient it will be. Diesel engines have far more reversible reactions that gasoline engines - making them more efficient (not to mention their higher compression ratios which also make them more efficient).
On the molecular level think of the molecules that compose the lattice of the piston being hit by very fast moving combustion product molecules and a vibration being induced (heating) as opposed to displacement (work).
It is the difference between pushing your friend slowly with one finger vs slapping him. One causes displacement, the other heating (and perhaps a fight). We are not interested in HEATING our pistons, we are interested in moving them.
...but did you know that if you had a higher compression Otto-Cycle engine, it would be more efficient that a diesel engine? In fact, the otto-cycle is superior in efficiency to a diesel cycle. The problem is that we have to run compression ratios that are far lower than those of diesel BECAUSE of the poor characteristics of gasoline. The long carbon chains and non-polar nature of gasoline molecules make it an easy target for the oxidizer. Alcohol suffers MUCH less from these limitations. It's polar nature and the presence of a far less reactive Oxygen molecule reduce the number of reactive collisions and thus the rate of reaction (also known as the reaction kinetics).
Liquid fuels have proven themselves to be convenient and effective. We have developed the infrastructure necessary to support them. Methanol can be produced from many sources. It is easily made from Natural Gas, Coal, Biomass, etc. The US produces in excess of 3.6 Billion gallons of Methanol per year from NG. I imagine that NZ does as well. It trades for about $1.00 per gallon...
Methanol production can be sustainable, doesn't have to come from food products and can be made from fossil fuels until we ramp up production of sustainable non-food plant matter. The use of Ethanol now is a good way to start towards production of methanol in the future. Farmers will now have TWO crops. The part that humans eat and the part of the plant that is inedible and can be easily converted to methanol.
(Biomass or NG or Coal or Dog droppings) + Steam -> Syngas (CO + H2)
CO + 2H2-> Methanol (over copper catalyst)
CO2 + 3H2 -> Methanol + Water (same catalyst)
This is an old reaction that we have used for a long time.
So, why are we do obsessed with gasoline... The smear against alcohol fuels has been long winded and purposeful... It harms us all. Our planet is suffering because of this fuel.
So yes, methanol has half the energy of gasoline, but with the proper engine, the efficiency for work conversion will go up by more than 200%!
As an analogy, assuming that you have 100 Joules of energy available (from gasoline) and you can convert 18% of that energy into useful work. You would get 18 Joules of work out of your engine.
Now assume you only have 50 joules of energy (from methanol) but you can convert (48% of that energy to useful work). You would get approximately 25 Joules of work out of your engine. Half the energy, but more useful work performed.
This is what we are talking about.
Yes, for a given quantity of air, more methanol will be needed to affect complete combustion. What I am saying is that your throttle plate will be closed more because you will need less power output because your engine will be more efficient. Less air for more work and therefore less fuel overall.
I say again, the solution will begin in the DIY community. Perhaps embarrassing the auto manufacturers can affect some change.
Quote:
Originally Posted by gmh308
We're interested in lowering our ET/TS in the quarter on our current hardware and want to stay within our small budget (if something breaks we have to be able to replace it cost-effectively)... how can alcohol/methanol help us...?
( for the average car guy, this is what it comes down to )
:)
I say we cut this thread in half and send the second half to the Lounge ??
-Justin
Both E-85 and M-100 (Methanol) will increase efficiency. So power WILL go up even if you have to burn more fuel.
I recently "rough tuned" a 2007 Chevy Cobalt. Stock tune with gasoline was 122 HP at the wheels.
Copied the HO Spark Table into the LO Spark table and adding 10 degrees of additional advance to the HO table and 6 degrees to of additional advance to the LO spark table resulted in an increase in power to 136 HP (Methanol) and 134 HP for E-85.
Mileage tests on gasoline for a 262 mile test (highway)
36 MPG Gasoline.
38 MPG E-85 - no hardware mods required.
30.3 MPG M-100 - one 35 cent seal required.
No detonation for either E-85 or methanol. I've done some reading about NZ. Apparently your country imports ALL of its oil. A while back, there was a program to produce synthetic gasoline.
Methanol -> Dimethyl Ether -> Propanol -> gasoline.
Very expensive and there is no need. You can run very well on methanol alone. Increasing the compression ratio in your engines will result not just in improved efficiency but also avoids cold starting issues.
In about 2 weeks, I will be testing a new algorithm for determining the most efficient spark table and will publish the tables for engines as I test them.
Here in the US, the cost of gasoline is running about $3.50/Gal. E-85 is about $2.90. M-100 is trading for about $1.04-$1.23 per gallon (varies daily). Of course, I am forced to run Reagent/Lab grade methanol purchased at $3.00 per gallon.
If we are to compare cost of driving on Methanol to Gasoline. The gasoline vehicle would have to get mileage 3x that of Methanol to equal the cost per mile driven for Methanol. Methanol is just a great fuel.
Yes, I realize that most on this site are interested in quarter mile times. (As am I, since cars are both a hobby and a profession for me) but seriously, the average "Joe" is interested in mileage not the quarter mile.
As for cars, I was first to put a Corvette Z06 engine into a Mazda Miata ("LS1 Bound" on Miata.net). I have two Corvettes (one that ran in Bonneville at 276 MPH) and one that is currently being set up as an open road racer.
I just think that mileage is more important for BOTH of our countries.
Quote:
Originally Posted by joecar
Are you serious? People dumped gasoline, ongoing, into the Ohio river. My god we have come a long way...luckily.Quote:
Originally Posted by samgm2
Got you on the combustion speed of gasoline. The impulse of the reaction. Needs to be more like the application of energy by a person on a bike.
Thanks for the overview. Very in depth. Interesting what you got out of the Cobalt with no comp ratio changes. The power increase sounds typical. Was it still running closed loop? If so, it means that just increasing the timing created so much more torque, that the airflow through the engine was reduced by a considerable amount and MPG went from a typical 25-30mpg on E85 up to 38mpg.
Looking forward to your work on the optimal timing. That could get my E85 drinking LS7 down to much cleaner gas type mileage while still making a lazy 700Nm TQ. (well, clean, acetyldehyde and formaldehyde aside :( ).
EFIlive is not all NZ. :) GMPX is in "Melben" as his sig says. And Mr Blacky resides in NZ, but I believe he is an Aussie as well.
I know a guy in the oil and gas business in Singapore...he got into that industry 20+ years ago. Apparently there was an oil shortage back then as well and continuously since. Nothing has changed except the price. Yes I agree, its all about money.
Smokey Yunick managed to build a very thermally efficient gasoline engine maybe 30 years ago. High power, low fuel consumption. That didnt get far. Killed off I guess. Hope your work survives. :)
Good analogy on the bike. Imagine if you slapped the pedals really hard - it just wouldn't yield much.
The history of gasoline is very interesting.
It was called gasoline because it was so volatile. If you put a can of it down and came back a day later, half of it was gone. Hence: GAS-O-LINE. The first part means it turns into a GAS.
The word Kero as in Kerosine comes from the Greek "Kero" which means waxy.
Fortunately we no longer dump gasoline into the Ohio and it no longer catches fire because Otto's engine found was able to use the waste product.
Nicholas Otto's engine caught on, BECAUSE it burned a waste product - so the inefficiency caused by the extremely low compression ratios didn't matter. The stuff was almost free (you just had to pay transportation costs).
Had gasoline not been available, the engine would have run on alcohol and would have had a much higher compression ratio (perhaps 20:1). This would have radically changed its efficiency.
Quote:
Originally Posted by gmh308
Yes, full power on the crank of a bike at TDC will take one a long way right! Rising power to 90 deg probably most effective.Quote:
Originally Posted by samgm2
Very informative. Gas-o-line. How much damage has unburned HC from that evap source done over time to the planet? I would guess there is more HC burned each day as waste on oil platforms than the entire motor vehicle population of the planet. Roughly speaking, one single platform off the north west coast of Australia, in one day, from its waste flame, creates more CO2 than the entire car/truck population in Sydney (4.5m people) does in a day.
Sam, I wish I had more time to experiment with an E85 specific tune for my car. It's the 3.0L LFW V6, direct injection with 11.7:1 compression, factory flex fuel. Unfortunately there is no specific adjustment to the cam timing on these engines based on the ethanol content (or we haven't found the table), this is an area I've played around with on normal gasoline but it's too prone to knock once you start playing around with the dynamic compression by altering the cam timing.
Any mileage measurements on E85 Ross?Quote:
Originally Posted by GMPX
Wow......to think all this time I thought you were just a programmer....Quote:
Originally Posted by GMPX
...oh wait that's paul. Ha ha
-Justin
91 Octane about 12.4L/100 city, on E85 15.8L/100. Feels lazy on E85 too. This was only reading 65% ethanol too as the tank was not empty when I put E85 in, so I expect it to be a little worse on full E85.Quote:
Originally Posted by gmh308
I don't know, i just copied from something Google found :hihi:Quote:
Originally Posted by L31Sleeper
Oki doki thx. Your mention of the VVT raises a good point, as the combination of VVT and ethanol makes it difficult to see what the timing needs to be without VVT.Quote:
Originally Posted by GMPX
Anyone have a 2011 VE Commodore V8 tune they could post? Being a VVT free engine... :)
I will be developing a more accurate tune for several ECOTEC engines. We will also be developing a more sophisticated algorithm for valve timing.
With such a compression ratio, you should be able to surpass both power and efficiency dramatically with and optimized E-85 tune. It should easily surpass what is possible with gasoline.
Did your engine come with 11.7:1 compression stock?
Quote:
Originally Posted by GMPX
Yes, according to GM's press release the LF1 / LFW are 11.7:1 comp.
I'm working with a 3900 V6 LZG engine (VVT, DOD, & Flex Fuel ). So far it looks like it uses the E38. Any idea if the Flex fuel sense option will work on this version of the OS?
It'd be a great thing to have when I drop a VGT turbo on it (Assuming I don't need an E67).
I have yet to find anyone that has confirmed that the flex parameters actually enable flex fuel operation. So far I have confirmed that people can shut it off, but I know of no one that has turned it on when it was off by default. This was certainly true of HP Tuners. Their flex fuel stuff didn't work for turning the function on. EFILive appears to have discovered more of the parameters, however. I am very interested in the answer and might just go ahead and burn up another license to find out.
I am in the process of installing our dyno at work. I expect it to be up and running next week. I expect to be able to derive some really good tables for both E-85, E-100 and M-100. I will make them available when I finish. Unfortunately, all of these engines are 4 cylinder for now. I will move to a v8 next (L92). Probably a v6 after that.
Boy, no kidding. I am 50. The 555 was old when I was a kid! I wouldn't use a 555 for anything anymore.
I completely agree about the AVRs. They are awesome. I just wish that documentation from ATMEL was a bit better. I've currently developing with a UC3C0512c. Amazing part. 32 bit, 66 MHz, 100 MHz DSP, 16 A/D ports, 2 DACs, I2C, SPI, USB, Flash, external memory support, great RISC instruction set and an industrial rating! It blazes! All for less than $20 in low quantities! Now that ATMEL has switched their IDE to microsoft, even the development environment has taken a giant leap forward.
Quote:
Originally Posted by GMPX
Unfortunately lurking in the ECM is many untapped calibrations that may stop Flex Fuel working even though you tell the ECM it's a FF engine. For example, all the Northstar V8 tunes have no base E85 calibrations set up at all, like GM knew this engine would never go to FlexFuel, so why bother. As a 'loose' rule, if the ECM has some ethanol tables populated (eg, the Stoich table not all one value) then you might get lucky in that all the underlying calibrations that make E85 work maybe populated with functional base values.Quote:
Originally Posted by samgm2
A few years back I messed around a bit with the Freescale MCF51 series, a great 32bit processor with everything you need and cheap as, like $3 ea. Problem was the dev environment was horrid (for me) as it was focused around C only programming.Quote:
Originally Posted by samgm2
Our first hardware (V1) used an AVR Mega8, unfortunately at the time the AVR CAN series was 'pending', we decided to go ahead and design V1 with no CAN ability (this was back in 2004 or so). This was a good decision rather than wait for the new chip as it took Atmel about 4 years to get that AVR CAN chip to market, even then it had bugs. I found AVR studio not too bad to work with as it's not 'C' or 'asm' orientated.
Ira (Fish Tuning) and I often have discussions on AVR's (riveting conversation for anyone listening in).
I wish Freescale would make a small 32 pin Micro with a PowerPC core :shock:
555 was new when I was a kid LOFL. So its only a couple years before it got "old" then. Yes why use a 555 when you can use an AVR. I use them as engine simulators and as a "virtual" flex fuel sensor LOL.Quote:
Originally Posted by samgm2
Didnt I tell you that Sam? :) Didnt make any of the details up! It was all hours of work - WITH - production VFS flex fuel tunes. Have never come across a tune that wouldnt work with the hard sensor selected. But some do not run the sensor fail test and go to the default ethanol content.Quote:
Originally Posted by samgm2
The AVRs are a decent chip to mess with. I'm pretty sure there are other PPC chips available perhaps a ARM series, though my experience setting up the Dev tool chain with Cortex A8s has been less then great.
I don't see why the virtual sensing of E85 content can't be used. You could 'just' as easily add a few CHT and EGT sensors to combine with the O2 sensor to pretty accurately estimate E85 content.
The 3900 V6 I'm messing with has Flex Fuel capability stock. I'm fairly sure the fuel system is different to handle the E85. Only certain elastomers and polymers are compatible with E85. I'm not sure however if straight gas parts are the same part number or not.
E85 has a huge advantage as its published octane rating is well over 105. If memory serves around 110. It should also burn a bit cooler (hence the reason CHT and EGTs with O2 would give you a decent idea what concentration you are running... especially if you throw air mass numbers into it as well... the stochiometry then becomes a somewhat simple thermodynamic calculation which I'm pretty sure the CPU can handle on the fly or at least an external AVR could).
When I priced a new E85 fuel pump from my project car they were around $350-$450 US.
I'm guessing GM is using the same parts for all cars but I could be wrong.
GM "virtual fuel sensor" flex fuel control uses O2 sensors to estimate and adjust for ethanol content. For some reason they have recently started going back to hard sensors. This may be due to the price. Originally (several years ago) they were around $400 as a part. Now they can be found for ~$80. Always driving cost out. Given every platform needs to be calibrated for VFS to work properly, a low cost (GM cost probably $5-$10), a hard sensor is a simpler value proposition.Quote:
Originally Posted by NateD4
Have been running E85 for around 3 years now...all on stock fuel system. Steel lines - bare metal exposed, rubber hose, normal Walbro pump. There is no corrosion - even on bare steel. The rubber hose is fine. Injectors are fine. Though I would guess on a car or truck that needs to deliver to a 100,000 mile warranty, is why GM is now using nylon when it is not using coated steel.
The injectors and valve seats are made from a slightly different material to meet durability objectives on flex fuel.
FYI - Intake valve temp is about 30C lower on E85. Approx 130C vs 160C on gas. So nice and cool.
Cheers.
I have a setup that I wish to be a truly flex fuel compatible automobile but I do not have a E38. I have a gen III 1mb pcm. I wish to run flex fuel and use something to simulate the flex fuel sensor signal or the sensor itself. If this is possible for the E38 Is it possible for the Gen III PCM?Quote:
Originally Posted by gmh308
2006 Silverado 5.3L PCM does Flex Fuel. :)Quote:
Originally Posted by lt1stang
I failed to mention that it is turbocharged and I want to use a COS to run a 2 or 3 bar map.Quote:
Originally Posted by gmh308
Fuel composition sensor - GM part # 12570260 - for use with 2002 to 2005 Gen III Flex Fuel engines.
Regards,
Taz
Holy Rip-off Batman, $313 for a FF sensor!, must be made by Mercedes.
It would be interesting to know what the sensor is that GM Holden are using on the 2010+ Commodore's. Holden's (we are talking E38 here) don't use the virtual sensor algo's, they have a real sensor, I've heard it's part of the fuel pump?
Yes sir ... GM list price is just over $600.Quote:
Originally Posted by GMPX
Cheers,
Taz