e85 and emissions!

[Adam Connell]

Any one know if e85 will help with emissions... my car has a brand new cat, but a blocked EGR. I am very reluctant to re enable my EGR because of how much smoother my car is running with it blocked... It passed C02 with flying colors but failed the NOX my almost double yesterday... SO I am going to change the oil(it's time to do it anyways), Change the plugs, and run it on a 50/50 E85 93 mix. thats what I normally run the car with anyways, but I put straight 93 in it for testing with the TT emissions chip... and I am going to change the fuel filter.

So do you think e85 will help or hurt my NOX readings?

Other than that I ran the car with a 3/4 mix of e85 in it today and it ran like a bat out of hell. Never ran it up to full boost, but it was extremely responsive and felt very strong... I think I might just have to think about a full e85 conversion!

 

[Pablo]

Any one know if e85 will help with emissions... my car has a brand new cat, but a blocked EGR. I am very reluctant to re enable my EGR because of how much smoother my car is running with it blocked... It passed C02 with flying colors but failed the NOX my almost double yesterday... SO I am going to change the oil(it's time to do it anyways), Change the plugs, and run it on a 50/50 E85 93 mix. thats what I normally run the car with anyways, but I put straight 93 in it for testing with the TT emissions chip... and I am going to change the fuel filter.

So do you think e85 will help or hurt my NOX readings?

Other than that I ran the car with a 3/4 mix of e85 in it today and it ran like a bat out of hell. Never ran it up to full boost, but it was extremely responsive and felt very strong... I think I might just have to think about a full e85 conversion!

It should help with NOX emissions significantly... so does EGR. NOX is formed by the very high temperatures that occur during combustion, it also is formed by the CAT since they run so hot. Believe it or not EGR cools the combustion chamber by recirculating exhaust gas. E85 should do the same thing since it runs so much cooler than gasoline.

 

[b4black]

I'm not sure it will help. E85 runs leaner at the same fuel level. I suspect the ECM will just dump in more fuel (from lamba sensor readings) to compensate until the injectors are maxed out. Once maxed out, the engine will go lean and hotter, making more NOx.

 

[Pablo]

I'm not sure it will help. E85 runs leaner at the same fuel level. I suspect the ECM will just dump in more fuel (from lamba sensor readings) to compensate until the injectors are maxed out. Once maxed out, the engine will go lean and hotter, making more NOx.

The injectors wont max out at part throttle. Your max injector duty cycle is going to be at peak torque @ wide open throttle. You wont be anywhere near that during any sniffer test.
What may happen is that you may reach the closed loop correction factor limit which iirc is around 15%. Generally I have seen people on average getting by with 20% more fuel at part throttle on e85.
To avoid this becoming a problem, you don't have to run straight e85. This is assuming you don't have another means of increasing the fuel flow via chip/translator/ fuel pressure. I personally would just bring up the fuel pressure for the purpose of the test.

Actually I would probably just reconnect EGR which should make it pass fine, this in addition to some E85 would be a pretty safe bet.

All things considered, even at a leaner AFR I'll bet the e85 has significantly less NOX emissions. It has a much higher latency of heat than gasoline. The only problem is that if you max out your BLMs (the correction factor) you'll end up with SES light which will probably automatically fail you (I'm guessing texas emissions are like anywhere else)

 

[Adam Connell]

Ok, so it failed again miserably on NOX with the E85... with the fresh Oil, fresh plugs, and new fuel filter... I had it set to 38psi on the emissions chip, so my guess is that it's lean. Im going to call the shop and tell them to bump up the pressure to 45psi and see if it makes any difference tomorrow... if not then Im going to have to pull the plenum off and drill the RJC plate(and I really dont want to do that...)

I bet this thing is just lean as hell and thats whats going on.... the C02 is almost non existent so I have some room to play with on tuning.

 

[Pablo]

Ok, so it failed again miserably on NOX with the E85... with the fresh Oil, fresh plugs, and new fuel filter... I had it set to 38psi on the emissions chip, so my guess is that it's lean. Im going to call the shop and tell them to bump up the pressure to 45psi and see if it makes any difference tomorrow... if not then Im going to have to pull the plenum off and drill the RJC plate(and I really dont want to do that...)

I bet this thing is just lean as hell and thats whats going on.... the C02 is almost non existent so I have some room to play with on tuning.

You ran straight e85? That's surprising. Mind posting your before and after numbers? NOX, HC, Co2, etc

Another thing that affects NOX emissions is timing. If you have part throttle timing too advanced, your NOX emissions go up. If egr is enabled in your chip, and you aren't using it, then you definitely have too much part throttle timing. When EGR is active there is timing added to the base spark map to compensate for the slower burn that EGR provides.

 

[Adam Connell]

You ran straight e85? That's surprising. Mind posting your before and after numbers? NOX, HC, Co2, etc

Another thing that affects NOX emissions is timing. If you have part throttle timing too advanced, your NOX emissions go up. If egr is enabled in your chip, and you aren't using it, then you definitely have too much part throttle timing. When EGR is active there is timing added to the base spark map to compensate for the slower burn that EGR provides.

I have not received any papers yet with any numbers on them, I just know that the car has failed twice. I will post up numbers when I get them... Im wondering if the emissions chip thinks my EGR works... What I do know is that my CO2 is next to nonexistent and that my NOX were double the allowed limit... if adding more fuel works, then we will see what happens.... I really just want the damn sticker... it's obscene that a car that is 20 years old and sees less than 3k a year has to even be emissions tested... 25 years is the grandfathered age in Texas... LAME! Since my CO2 is so low I may just keep on having them turn the fuel up if 45lbs does not cut it... we will see I guess.

 

[GNVYUS 1]

Post some data for us on your tune via Scanmaster etc.
Pablo has a good point on the EGR and timing so I'd look into putting the EGR back on for the test.

I don't get the RJC plate and the drilling, are you talking about opening up the EGR towers hole in the intake as if you have it filled and welded??

How old is the 02 sensor, coil pack and what's your plug gap?

The 50/50 E85 should've dropped your NOX, it sounds like it's pretty much the same, true??

 

[ijames]

Don't drill the rjc plate itself, just take it and one gasket out for now! If the manifold has been welded you probably can't drill it all back out, and if you have ported iron heads the egr passages there might be filled with aluminum (and if you have aftermaket aluminum heads they don't have the passages anyway). Try to get all the numbers from each test and post them along with all the changes for each test.

 

[b4black]

All things considered, even at a leaner AFR I'll bet the e85 has significantly less NOX emissions. It has a much higher latency of heat than gasoline.

The heat absorbed by ethanol going from liquid to gaseous is small when compared to the addtional heat from leaner combustion or lack of EGR.



Notice that FFV's running on E85 still use EGR and they can't brag about better emissions. "Clean" ethanol is a myth left over from the gasohol days when cars didn't have computers and running lean helped lower HC and CO.

 

[Pablo]

The heat absorbed by ethanol going from liquid to gaseous is small when compared to the addtional heat from leaner combustion or lack of EGR.



Notice that FFV's running on E85 still use EGR and they can't brag about better emissions. "Clean" ethanol is a myth left over from the gasohol days when cars didn't have computers and running lean helped lower HC and CO.

You are only leaner if you're tune isn't correcting for it (automatically or otherwise) so the difference there should be a net decrease in NOX

The EGR may be so, but don't forget the additional timing the computer adds when it thinks EGR is operational.

As far as E85 not being cleaner... everything I've seen and read thus far has been that it is cleaner with large reductions in carbon monoxide. Admittedly I haven't looked at it in depth, care to share your sources that have found otherwise? I'd like to take a look.

 

[bsdlinux]

E-85 is definitely cleaner in some areas such as Monoxide as Pablo said. However it does produce increased emissions of other gases and pollutants as compared to gasoline.

One of the best things about of E-85 is the reduced particulant matter ie, carbon. E-85 cleans the hell out of the combustion chamber, exhaust, etc. In fact my tailpipe turned from black to an almost grayish color inside. My spark plugs are always white and you cannot fuel foul plugs with E-85. It is definitely cleaner and better for the engine in regards to harmful deposits. A cleaner engine is a happier engine..no doubt:biggrin:

I've passed emissions with E-85 just fine. One of the nuiances of running E-85 though is that if your serious about running it, take your 160 tstat and chunk it and put nothing less than a 180 degree one in. I run a 195 degree tsat. The E-85 will really appreciate the extra heat and it will also help you NOX readings and mileage. I know using a hotter tstat is counter intuitive of what we all do here but E-85 takes a little different approach to tune it and get the most out it.