Post Reply 
 
Thread Rating:
  • 1 Votes - 3 Average
  • 1
  • 2
  • 3
  • 4
  • 5
EFIE Question
Author Message
SloobyLoo Offline
Member
***

Posts: 12
Joined: Jul 2010
Reputation: 0
Post: #1
EFIE Question
Hi,

I have a slightly different use for the EFIE than the HHO norm around here, my car runs on LPG and Petrol. While running on LPG the AFR sensor returns readings that cause the cars ECU to run the car too rich on LPG. I want to apply a correctional voltage to the AFR signal while the LPG system is on.

I have looked at the Dual Wide Band EFIE and I can see how to hook it up but it appears to me that there is no place to hook up the incoming signal to the ECU. Am I correct in thinking that the EFIE does not apply a correctional voltage but in fact generates a completely separate and autonomous signal? I actually want to correct the signal by x% some of the time (while on LPG) but otherwise have the thing running as normal.

Making sense?

Thanks in advance.

S
(This post was last modified: 07-06-2010 03:02 PM by SloobyLoo.)
07-06-2010 03:00 PM
Find all posts by this user Quote this message in a reply
mike Offline
Senior Member
****

Posts: 2,020
Joined: Jul 2007
Reputation: 7
Post: #2
RE: EFIE Question
Yes, I understand.

The EFIE will apply a change to the signal that is proportionate to the position of its adjustment pot. To go back to stock, you just take power away from the EFIE. All of our EFIEs work this way, including those for narrow band sensors.

I will recommend that you not just treat your upstream wide band sensor(s), but also your downstream, narrow band sensor(s). If you write into us at support@fuelsaver-mpg.com with your vehicle make/model/year/engine size, we'll look it up for you to make sure you're getting the correct product.

[Image: signature.gif]
Visit Our Documents Page
07-06-2010 03:36 PM
Visit this user's website Find all posts by this user Quote this message in a reply
SloobyLoo Offline
Member
***

Posts: 12
Joined: Jul 2010
Reputation: 0
Post: #3
RE: EFIE Question
OK, I will email you.

Am I misunderstanding the installation? Do you break the sensor signal wire or graft it into it? If its is broken then where does the line from the sensor end up going? Is there wiring diags I have missed?
07-06-2010 03:45 PM
Find all posts by this user Quote this message in a reply
mike Offline
Senior Member
****

Posts: 2,020
Joined: Jul 2007
Reputation: 7
Post: #4
RE: EFIE Question
Not for the wideband or AFR EFIE. You do break the wire on the narrow band models. The wide band, when the power is off, becomes an inert device connected to your signal wire. Since you haven't cut the wire, but merely tapped into it, no relay is needed. See the installation instructions for more detailed info on this: http://www.fuelsaver-mpg.com/doc/afr_efie_install.html

But for the analog versions, the wire is cut and goes through a relay on our board. When the board is powered down, the relay falls closed and connects the signal wire directly to the computer.

Functionally, they both are the same. No power to EFIE = no affect to the sensor's signal. The signals go directly to the computer, unchanged.

[Image: signature.gif]
Visit Our Documents Page
07-06-2010 03:55 PM
Visit this user's website Find all posts by this user Quote this message in a reply
SloobyLoo Offline
Member
***

Posts: 12
Joined: Jul 2010
Reputation: 0
Post: #5
RE: EFIE Question
That is good! I can pickup the power from the LPG's injector controller so that it is only running when the LPG injectors are firing.
07-06-2010 03:59 PM
Find all posts by this user Quote this message in a reply
mike Offline
Senior Member
****

Posts: 2,020
Joined: Jul 2007
Reputation: 7
Post: #6
RE: EFIE Question
Yes, that should do nicely.

[Image: signature.gif]
Visit Our Documents Page
07-08-2010 09:18 AM
Visit this user's website Find all posts by this user Quote this message in a reply
missangelina Offline
Member
***

Posts: 1
Joined: Sep 2010
Reputation: 0
Post: #7
RE: EFIE Question
how will I know that the LPG is leaking or not?

_______________
pmp questions free
09-09-2010 10:24 PM
Visit this user's website Find all posts by this user Quote this message in a reply
SloobyLoo Offline
Member
***

Posts: 12
Joined: Jul 2010
Reputation: 0
Post: #8
RE: EFIE Question
(09-09-2010 10:24 PM)missangelina Wrote:  how will I know that the LPG is leaking or not?

Not sure how that is relevant but the LPG system runs its fuel rail at 3 bar so leaks are very apparent (would be quite spectacular really) anyway should it happen the pressure drop sets off a shut off valve.
09-10-2010 02:27 AM
Find all posts by this user Quote this message in a reply
SloobyLoo Offline
Member
***

Posts: 12
Joined: Jul 2010
Reputation: 0
Post: #9
RE: EFIE Question
Mike,

I finally set up the EFIE's! A bit bummed that the new product came out in the mean time, it was a big stuff around fitting the old ones neatly, modern 4's have no room under that hood, the new one is a much better idea! I have no idea about performance yet but I have set the AF EFIE up at around .20 of a turn and the 02 at 200mv. That appears to have pulled out around 5% out of the fuel trims at idle when running on LPG. After driving it appears to result in a -5% to -7% trim. I have no idea of mileage yet but I will be keeping a close eye on it and pulling my spark plugs regularly to look for signs of plugs that are running hot. Its very easy to fry valves with LPG!

Just by the way, I suggest that the folk that play with HHO and your products actually learn to read spark plugs for signs of an engine that is burning too lean. There are guides available on the web and its quite simple to pull a plug every few hundred miles until you are satisfied you are not doing damage to the engine. It may prevent the heart ache of a top end rebuild for some adventurous HHOer's. I only mention this because I have not seen mention of it anywhere in my browsing for info relating to EFIEs.

RE: The treatment of the post cat sensor.

I suspect that the post cat sensors is not actually used in fuel calculations at all but rather it is used in the calculation of the cat temperature. For a catalytic converter to operate efficiently it must burn in a certain temperature range so if the detected temperature is not high enough I suspect that the ECU is adding more fuel to make the temperature gains needed thus negating any gains made by just treating the AF sensor. As long as the ECU can add fuel and stay within its fuel mapping this option is probably taken, the assumption being that the AF sensor is not quite preforming to requirements or the cat is beginning to fail. Once the ECU hits the limit of its engine mapping my guess is you will get a code of one sort or another. This is why you will probably only face this issue with say Euro4 and newer/higher cat standards. Ironically we burn more fuel to get cleaner air. I am told that had we pursued "lean burn" technology as apposed to cat tech we could possibly have achieved the same air quality standards using a lot less fuel.

It is just a hunch but if you are experimenting with a car I suggest that you start to note the reported Cat temp verses its operating temperature thresholds and see if there is any correlation with loss of fuel savings provided by the treatment of the AF sensor. Preserving any gains made by treating the AF sensors may be as simple as raising the post cat sensor voltage until the cat's minimum threshold temperature is achieved.

If this is the case the downside to this is; its likely that overtime the catalytic converter will just start to clog up and fail because of the unburned debris. This is an assumption on my part, you'd need to talk to an expert but it makes sense to me. The remedy could be as simple as the occasional good hard run, in standard trim with enhancements switched off, just to burn the debris out of the cat. As I am running LPG, which is an extremely clean burning fuel, I'm not likely to find out if this is the case.

Anyway, just a thought... maybe you have already had it!

Cheers
S
(This post was last modified: 10-09-2010 02:36 PM by SloobyLoo.)
10-09-2010 02:23 PM
Find all posts by this user Quote this message in a reply
mike Offline
Senior Member
****

Posts: 2,020
Joined: Jul 2007
Reputation: 7
Post: #10
RE: EFIE Question
Good tip on checking the spark plugs. I'll get it into our documents somewhere. However, you don't hear about too-lean type damage, because it really just never happens. Using gas, we're really not trying to lean the mix. We're actually trying to un-richen it. The HHO fools the computer into adding more gas than it would normally. We're just trying to undo that action. Usually the vehicle's computer is resisting our efforts anyway, so it usually ends up still being correct, or even a bit rich in the final analysis.

You, on the other hand, don't have any room for error with that LPG. You don't have the quenching effect of the liquid fuel, so will be more susceptible to over heat.

As for post cat sensors, in some cases, they are only used for cat monitoring, as you suggest. However, as models get into later years, more and more of them are using the downstream sensors in air/fuel calculations. The Dodge pickups, for instance, have been documenting this use of the downstream sensors since before the year 2000. Honda was similar. But now most makers do this. Fords still don't document it (that I have seen), but we have debugged a number of F150 projects by adding EFIEs to the downstream sensors. It is prevalent enough, that we now make our EFIEs to treat all the sensors. See our Digital and Wideband series. Both are equipped now with analog EFIEs for the downstream sensors as well as the upstream EFIEs.

Lower fuel mileage is not actually considered to be in the best interests of the largest vested interests in the automotive industry. That's why it hasn't improved. My old 75 Toyota Corolla used to get over 40 mpg in combined driving. Now you have to get an electric hybrid to get that mileage. And they still haven't improved on it. What does that tell you?

[Image: signature.gif]
Visit Our Documents Page
10-11-2010 12:00 PM
Visit this user's website Find all posts by this user Quote this message in a reply
Post Reply 


Forum Jump:


User(s) browsing this thread: 1 Guest(s)