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air fuel ratios???

9K views 62 replies 12 participants last post by  Con 
#1 ·
Hi just installeed a fuel air meter today and found that my car runs lean to stoic at light throttle and part throttle....At full throttle it reads full on stoic and does not ever hit the rich sector at all .It does not run rich....are these the ideal readings?
 
#8 ·
not yet...I am skeptical at how much a chip really does...If a chip simply modifies air fuel ratio at low to moderate throttle..then i think i can do it..If a chip can advance the timing..again I think that I can do it..The only thing I am not certain of modifying yet is wot air fuel mixtures..The car is said to go into closed loop mode and reads of the programmed ford maps..These maps are always running a rich mixture on all cars..the ego sensor is then ignored .....if I think I am close to doing it myself .the difference if I pull it off is say around 40 dollars useless kit as opposed to 1300 dollars odd for a unichip...people like you and me made unichip..not god..and while it is great I like to push my mind to the limit and further my limits ..so once again id like to try...I will ..if I cant ..i will probably call spiro..
 
#9 ·
useless your not still trying to crack the eec-V ?

Its been around a while and I don't think anyone has been able to do it!

You can bypass it thorough the OBD port and use interceptors but reflash it with your own custom program sounds like too much work. If you do it you would be crazy to then give it away in kit form for a few $

Wait for the chip challenge stuff from Casper if he ever gets it finished and see what the chiptorque and unichip did in a fairly well controlled back to back test.

The results whatever they are will be hard to ignore.

By the way I am amazed yours runs so lean even with the DEV4 as mine is so rich its not funny. I checked my plugs again today Autolite 985 (Dev spark plugs) and they are black and sooty!!! SO is the tailpipe, tailgate, garage door where I park etc.

I got to get this Unichip soon!
 
#10 ·
jonbays said:
useless your not still trying to crack the eec-V ?

Its been around a while and I don't think anyone has been able to do it!

You can bypass it thorough the OBD port and use interceptors but reflash it with your own custom program sounds like too much work. If you do it you would be crazy to then give it away in kit form for a few $

Wait for the chip challenge stuff from Casper if he ever gets it finished and see what the chiptorque and unichip did in a fairly well controlled back to back test.

The results whatever they are will be hard to ignore.

By the way I am amazed yours runs so lean even with the DEV4 as mine is so rich its not funny. I checked my plugs again today Autolite 985 (Dev spark plugs) and they are black and sooty!!! SO is the tailpipe, tailgate, garage door where I park etc.

I got to get this Unichip soon!
Mate no one..not even unichip have cracked the eecv.It is merely a matter of locating the electronic inputs to the vehicle which tell the computer how to behave.And beleive me that I have run it in my mind a million times.As you know car electronics is my life.And I have installed laptop computers in cars rf leakage detectors and items which people did not know existed...If you can alter the input signals to suit yourself then you will be essentially altering the parameters of your vehicles responses in its pcm computer.I find it fairly simplistic in theory..And I am so confident that I will be able to tailor my car in the near future with a turn of a dashmount dial or 2..OR..even via the power button place in our centre consoles...Lokk at the shift kit for example...we can already flick a switch and the gears go well.Why not air fuel mixture?Why not timing?I beleive I am really close Jon but as you know it may well be a flop..But im a cluey guy at this sort of thing and while I have the utmost respect for unichip and the likes it does not hurt in trying...


ps do you remember when we were asked at autotech day why putting on an exhaust creates a richer fuel mixture??Well I somehow knew the answer...and answered it correctly..its just the way my mind works...
 
#15 ·
Might very well be a dud MAP sensor in mine all right as the symptoms are very similar. If its a dud though its just out of calibration from factory and the ecu is obvoiusly designed to cope with a variety of sensors all at the wrong end of their calibraton or service life by running rich.

The thing is if i put in a unichip it will intercept the dud MAP info and correct it!
So do I do both?

I have dialled the cam in a million times trying to fix a doughy bottom end and mid range and bascily learned a lot but got no where in particular. My plugs were fine a nice mid brown till I put the cam in though though never white.
 
#18 ·
jonbays said:
The thing is if i put in a unichip it will intercept the dud MAP info and correct it!
So do I do both?
The unichip can only dial out so much, its parameters are not infinate. If its running too rich it may not be able to pull enough fuel out or have enough tuning points to compensate totally. This makes for an "interesting" setup.

Oh, and yes, I know this for a fact LOL. Fix the mega rich problem first...trust me.
 
#22 ·
Jon Bays..think about it.....Our pcm rely on tps ,ego ,map sensor to monitor air fuel ratios..right?So what does the tps do?? Well it is nothing but a potentiometer..a resistor like a tv dial ..no big deal...The resistances it relays to the pcm(computer)determines how open throttle is ..ok?
So if you alter the resistances a little (like to a slightly more open throttle position)should that be the first step to tricking the pcm to alter the fuel mixtures????I think yes....it thinks the throttles opened more ....
Then at the same time we have our lovely map sensor which is telling the computer the flow of air going into the throttle body ok?So I can only asume that it sends either low voltage pulses tio the pcm or a set of resistances..right?..Yep I think im right...Lastly we have the poor ego sensor coping the heat and measuring the oxygen left after each combustion cycle...From memory it gives out avariable reading to a maximum of 1 volt ..to indicate to the pcm either a lean or rich mixture..ok?
See where I am coming from???It can be done ..I am pretty sure of it..But as always Bloody Murphys law is in the wings to screw me up
 
#23 ·
I agree useless, there isn't that much to most of those aftermarket chips.
Another easy way to fool the ECU into changing the mixtures is changing what it sees from the temp sensor, and this is also achieved with resistors.

We may need to get together and work this out matey....

Rick.
 
#24 ·
Mate I totally agree but we better do it soon ....At the end of next month I will be tied up in a big way...You have the mechanical know how and I my brain loves electronics...and we are both not scared to take on a challenge.Ps I dontsee why we cant have the economy button to make our cars have a "stock" and "hot" mode..and control a few of these variable including ignition timing...One press of a button I like it... :angel:
stav
 
#25 ·
I think my MAP may be stuffed like Caspers or at least far enough at one end of the normal factory range to be too rich through most of its range. I will get the multi meter out and look at some voltage values and see if its in range or what. I have a MAP sensor Kpa and voltage table but I am not sure if I can test it properly

I think I will pobably change it and see what happens. I would like to get a dyno run with A/f ratios done first so I can quantify the difference but I will be spending money I want to spend on the Unichip so I am not sure whether I will bother.

The TPS I have played with quite extensively ( trying to get a nice idle) and this isn't the answer. its a dumb potentiometer all right but the ecu really only reads it as off idle mode, on run mode and WOT full throttle. So the ecu only looks for three settings. Its easy to test with a meter though just put a meter on it and check the voltage moves smoothly from 0.7v to 4.5v. Smoothly is what you're looking for.

The air and coolant temp sensors are also easy to test and modify. if its richer you want thats easy (I could really stuff my idle up with this) but if its leaner there are problems. I have tried leaning it out and the ecu decided the engine was cooking and went into limp home. You know beacuse the FAIL on the dash LCD display and all of a sudden the launch goes from bad to sad as it stays in third gear.

I am an electronics technician by trade and I have tried to see what could be done but I am coming round to the Unichip interceptor as the best way forward to tune t he falcon for themoney I would spend on my car. My only gripe is they don'y let you get some real time stats out of it and let you reload multiple interception programs from a laptop.

I have to keep telling myself its not a race car its not really worth it but i just can't help tinkering anyway.
 
#26 ·
Hahah...Jon bays ..legend...you have just answered my question without even knowing it!!!
If voltage moves smoothly from 0.7v to 4.5v.then guess what the computer would be reading this every step of the way!!!!Think about it....If the pcm only read it as off idle mode, on run mode and WOT full throttle then it would not be important that the voltages be smooth...You would only have 3 trigger points and not a smooth voltage increase!!!! The existing pcm setup must compensate at all throttle positions or the car would have a lean misfire or be running really rich!!!Like the old carbies...in response to venturi effect and releasing more fuel!!!

Youve done it mate youve done it!!!So,,the next step is to find the finer added resistance to lean this out!!!

in the same step you have pointed me inthe vague direction of gear shift points..
 
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