Mf2 help!

[sexoturbs]

does any one know much about the mf2? i have just fitted a fith injector 2 bar map sensor to my vtr but the mf2 dosent seem to function as it should all im getting is 1 red light come up when i plug it in.

[gd16]

If all you're getting is 1 red light, i'm guessing the RPM feed hasn't been connected. The lights along the top should light up every thousand RPM if set up correctly.

You also need to set up the threshold limit - IE the pressure level at which the MF2 starts firing the injector(s). This will set off another light any time the threshold is passed.

Then you need to adjust the fuelling at each load point to suit the AFR, which will in turn light up another light when the injector is firing.

[sexoturbs]

ok yea the light that is comin up red says input threshold...

i dont no much about this but i wired it up as the manues sed...

white and black - earth
blue and orange - 2 bar map sensor
red - battery (fused) and injector
brown - injector

its just the yellow im unsure about. it says coul pack. thers a plug on the top with 4 parts i could connect it to. i put it to the 1 that goes to the earth wer the little box is?

and their is a brown cable tht comes off my map sensor but im unsure where that goes?

anny ideas?

[gd16]

Yellow cable will be the RPM feed. Wire number 425 you'll find either coming off the ECU, or you'll find another at the diagnostic port probably.

MAP sensor will have 3 pins on it - one earth, one 5v, one signal.


Haven't got the manual in front of me - but it should tell you which wire from the MF2 you hook up to each pin on the MAP sensor.

[sexoturbs]

ok cheers m8 how can i find this wire no425? in a saxo manuel? at least i no wer i went wrong. yh the map sensore is set up right then it was just when i earthed the map senser the input threshold light went off. didnt no weather that was good or bad. but when i started the car up no lights came on. so it must just be that yellow cable. do you no if it matter wat year the saxo is?

[gd16]

Should be the same wire (425) in all saxo's/106s. Its the wire that sends the tacho signal from the ECU, to the diagnostic port, onto the dash.

Haynes manual should be able to tell you where it is.

[sexoturbs]

ok cheers

[sexoturbs]

i just downloaded that haynes manuel and had a look but couldnt see it anywhere. it has alot about standard mods. i found a diagram on the net...
( http://media.photobucket.com/image/saxo%20vtr%20ecu%20diagram/Saxo-Harv/wiring.jpg )

this shows wire 425 it says its a green cable that comes off the ecu but their is more thn 1 green cable :S

[sexoturbs]

ok, my mf2 is wired up now, it is reading my car fine as its lighting up as it should when my revs get higher. but the fith injector is not spitting no fuel. i have tested the injector alone and it works. but wen its all wired up no fuel is coming out :S any one no what this might be?

[gd16]

Does the threshold light show up on the MF2?
If not, adjust the MF2 to come in on the transition between vacuum and boost.

If that lights up, does the injector light show up on the MF2?
If not, adjust the fuelling using the pots along the top for each RPM step.

If you want to test it, just set both really low. IE threshold right down low so the threshold is easily met, then set the injector pot to kick in at the first RPM step.

If you're getting both the threshold, and injector lights on - but no fuel out the injector. Check the ohmage/impendance of the injector is correct and not burning out the driver, and check the wiring for it is correct.

[sliderz]

very usefull info that was ,due to do my mf2 very soon

[sexoturbs]

ok, when i start my car no lights come up at all, when i rev the car it starts to light up and matches my rev range every 2k 3k 4k...

i will try what u said. do i need to do this on a rolling road? or when driving? its under my bonnet so i cant see how its workin when im driving only when its parked.

[gd16]

To set up the boost threshold, you don't need a rolling road. As long as the MF2 has power and is getting a MAP signal, find someway of making the map signal no boost/no vacuum.

For adjusting the fuelling - if you've installed it under your bonnet - then you've got two choices.

Either map it on a rolling road, as you wont be able to adjust the fuelling ect whilst driving on the road.

Or (what i would do either way)

Spend a fiver at a computer shop, and get a 2/3/5 meter serial cable extension. Remove the MF2, plug one end of the extension into the red serial connector, feed the extension into the passenger compartment, and plug the MF2 into the other end. Means the MF2 is still wired in, but now you've got a lot more freedom, and more importantly its in a place where you can make adjustments whilst driving (or should i say, one person can make adjustments whilst another drives)


If you're mapping the fuelling yourself, you'll definately need a wideband AFR gauge (not a narrowband one, or a display that hooks up to your standard sensor). Even if you're getting it mapped at a rolling road, i'd advise an AFR gauge so you can keep an eye on the fuelling day-to-day. Last thing you want is it running lean and melting pistons :O

[sexoturbs]

ok what i will do, ill take the whole thing off agen then wire it thru the car so i have the mf2 inside.

i no my mf2 is getting power as it lights up as i raise my rpm. but my 2 bar map sensor dont have any light on it at all so not shure how its working. its wired up as to the manuel but thers a pipe tht comes off it and has just bn pushed into my down pipe tht goes to inlet manifold. should their be a sensor on the end of this?

could i not t piece the 2 bar map sensor to the pipe i have going to my boost guage?

http://cgi.ebay.co.uk/52mm-BLUE-DIGITAL-WIDEBAND-AIR-FUEL-RATIO-AFR-GAUGE_W0QQitemZ110411899299QQcmdZViewItemQQptZUK_C arsParts_Vehicles_CarParts_SM?hash=item19b50fe1a3&_trksid=p3286.c0.m14&_trkparms=65%3A2%7C66%3A2%7C39%3A1%7C293%3A1%7C294 %3A50 them afr's are expensive! would one like this be suitable?

[Spanky]

sorry to hijack the thread a little here but this is a damn good read :)

Im also going to be doing the same as you mate so just keeping an eye.

couple of things id like to ask though (saves making a new thread :homme:)

I will have mine wired into the car for the mapping side of things as me and a friend are just going to drive the car and map along the way.

Will have a AFR gauge in place.

Is it basically just a case of keeping the AFR gauge in the "optimal" section at all times through out the rev range.

for example, could i drive along keeping it at 4k and set it so its optimal, then increase it abit to 5k and set for that??

just thought it would need mapping on full throttle maybe...

im unsure.

As obviously more fuel is going in at full throttle compared to half throttle so how do you map both up??

God ive probably made that sound very complicated :S :S

[sexoturbs]

mf2 is workin all good :D fith in jector is on.. threshold light is on constant. my map sensor was blocked some how :S but its all good now. i will get my car remaped. and tune my fith injector on the rolling road...

[Dboyvts]

In my opinion i would always run a mf2 with a sid con3. As stew has said just make sure your injectors are the right impedance cose if they are to high a ohm or to low they can cook the mf2 driver.

[sexoturbs]

yea i will check that, its one that came with the kit but will check it still.

[sexoturbs]

whats a sid con3??

[gd16]

ok what i will do, ill take the whole thing off agen then wire it thru the car so i have the mf2 inside.

Serial cable will be much easier. Also means that you once you've mapped it, you can plug it back in under the engine bay and it stops you or someone else playing about with it potentially messing up the fuelling



could i not t piece the 2 bar map sensor to the pipe i have going to my boost guage?

http://cgi.ebay.co.uk/52mm-BLUE-DIGITAL-WIDEBAND-AIR-FUEL-RATIO-AFR-GAUGE_W0QQitemZ110411899299QQcmdZViewItemQQptZUK_C arsParts_Vehicles_CarParts_SM?hash=item19b50fe1a3&_trksid=p3286.c0.m14&_trkparms=65%3A2%7C66%3A2%7C39%3A1%7C293%3A1%7C294 %3A50 them afr's are expensive! would one like this be suitable?

Yes, you could T piece the MAP sensor vacuum hose into the same one as your boost gauge. Anywhere were it'll get a true inlet pressure reading will do.

Proper wideband AFR's are expensive, but cheap reassurance that your fuelling is fine. Also means you can map your car yourself - which pays for itself if you need it mapped twice, as a garage will be £80+ each time to map it i'd guess.

That one would be suitable. However - i would get one that can also output the wideband signal, in case in the future you upgrade to a standalone ECU, you can use this wideband AFR with it. Saves buying a compatible one at a later date. Also - personal preference, but you might want one that shows coloured LEDs instead of a number. Depends what your visual correspondance is like. If you're using it to map the fuelling, i used to find it a lot easier to work out if more/less fuel was needed by how many LEDs were lit up on my AFR, instead of working out if the AFR number is too high or too low.

The one i had was a Weber AFR, but didn't have the signal output i suggested above;

http://i52.photobucket.com/albums/g39/gd16/s413and/cconsole.jpg
Weber AFR is the one with coloured LEDs where the head unit normally goes, KMS wideband in the cubby hole.



I will have mine wired into the car for the mapping side of things as me and a friend are just going to drive the car and map along the way.

Will have a AFR gauge in place.

Is it basically just a case of keeping the AFR gauge in the "optimal" section at all times through out the rev range.

for example, could i drive along keeping it at 4k and set it so its optimal, then increase it abit to 5k and set for that??


More or less as you've said. Once you've set it up, made sure that the RPM readings are correct (every 1k rpm, but not neccesailry at 1000,2000 etc, maybe at 1234,2234,3234 etc) on the MF2, and that the threshold light comes on at the vacuum/boost changover point, and that the injector fires when set - your ready to map it.

Best bet is to find a very long private straight. One person driving, one mapping. The driver stays off boost and gets the car into 4th at very low revs. Then basically foot to the floor. Obviously private road is needed as you'll not only get to the top of 4th gear, but you'd have to deal with traffic ect otherwise.

Person mapping then looks at the AFR, and makes sure that it is constantly at the correct fuelling level by adjusting the MF2. Theres loads of adjustment pots along the top, the one thats lit up corresponds to the one you want to adjust. Obviously if things are happening to quick, get the driver to slow back down and redo the points again and again.

The reason the driver has there foot to the floor, is it means that the max boost pressure is seen, and that the fuelling is mapped for max pressure at that revs. Because we're mapping against a MAP sensor, it means that if you hit the same rev point, with only half the boost pressure, it'll only fire the injector half of the max fuelling.

Likewise, say the first fuelling point fires the injector 30%, and the second fuelling point fires the injector at 50%. Half way between these two points (revs) - the injector will fire 40%. Basically, it interpolates not only between rpm points - but also between the boost threshold pressure and max pressure for each point. Basically a 3D map.

Once you've gone over the full rpm range, and you're happy that the fuelling seems fine, do the run a few more times just to make sure. Even when i was doing minor changes i'd go over it 2 or 3 times doing the changes, then another once or twice to make sure i was happy with it.

Also bare in mind that the MF2 is a fairly primative fuel injector driver. It doesn't take into consideration inlet temps, coolant temps, etc etc. So if you map it on a very hot, humid day - the mapping needed might be slightly different for a dry, cool day.

So if the fuelling is spot on on a very hot day with high inlet temps, less oxygen will be getting into the engine and therefore less fuel is needed. If this fuelling is kept and then ran on a very cool day - lower inlet temps means more oxygen going in, which needs more fuel. Because the MF2 doesn't do temp corrections - it'll still be set to put the same 'smaller' amount of fuel it needed on a hot day, and the engine will run lean due to too much oxygen/not enough fuel - and eventually pistons wont want to play anymore. Good reason to buy a decent AFR gauge and keep an eye on it, also a good reason to map on a cool day - as overfuelling on hot day IMO is slightly better than underfuelling on a cool day, and really - is the best reason why you might want to move from MF2 > Standalone ECU.

whats a sid con3??

Miss-type from Neil. Sig Con 3 = Signal Conditioner 3

Basically an electronic box of tricks sold by GMC, that stops your standard ECU from fighting with the extra fuel that the MF2 is chucking in. I'm not 100% sure its needed tbh, although i did run one on mine. The theory is sound, but weather you'd actually notice much difference with/without one i don't know.

Basically the standard ECU adjusts the fuelling dependant on many things, one being the standard lambda signal. With the MF2 chucking in extra fuel on boost, the standard ECU may think too much fuel is going in and try to lean out the standard injectors. Which is bad obviously.

Now the standard ECU ignores the standard lambda signal if TPS (Throttle Position) is fully open. So basically if your foots to the floor, it ignores the standard lambda signal - so wont try lean out what it would think is the engine running rich (as it has to run a bit richer than standard with boost)

However, you'll quite often get points where you're on boost, but not got your foor to the floor. So the MF2 chucks fuel in with the extra injectors, the standard ECU removes fuel from the standard ones. Stuttering/Poor fuelling results. The Sig Con basically tricks the engine in to thinking that the TPS is fully open whenever boost is seen. Because of this, whenever boost is seen - the standard ECU ignores the standard lambda sensor and chucks in the default fuel for that RPM. And the MF2 chucks in the extra for the boost. Making boost at low throttle openings nicer/smoother.

[gd16]

I'm surprised theres no character limits on posts :) Didn't think that would all post in one lol :y:

[sexoturbs]

haha i had to get my reading glasses out for tht lol, gr8 post tho it all makes sence now :)

i see what you mean with your afr being much easier to read. i will definatly look into getting one of them..

i went outside to re-wire my mf2 it looked like a whole load of work for nothing, i saw tht the fith injector was workin turned everything bk down n strolled back in :) it will be tuned on a rolling road end of the month so i will leave everything on low untill then

sig-con3 sounds like a good tool, i will have a look around for one.

when my mf2 is finished (tuned properly) sould i take my car to get remaped after? or before?

[gd16]

when my mf2 is finished (tuned properly) sould i take my car to get remaped after? or before?

Slighty confused as to what you mean by this.

The MF2 is basically adding the extra fuel needed for boost - so instead of getting the ECU remapped to add extra fuel, the MF2 is doing it for you.

[sexoturbs]

ok. i just for it would be better if i got my standard ecu mapped aswell. but if u think it will be ok just doing the mf2 then i will get that done.

[sexoturbs]

http://i970.photobucket.com/albums/ae185/sexoturbs/DSC00019.jpg

[gd16]

Nope - no point getting your standard ECU remapped as well as an MF2. One or the other, no point in doing both as either one would do the job*



* Standard ECU remapped would need the 2 bar MAP sensor, and 4 uprated injectors instead of the standard ones.

[sexoturbs]

yep, well im gonna se how well this runs for a wile then i will buy a new car and start over with the saxo rebuild and do it all properly. :)

[Spanky]

Thanks alot for that, shoud be stickied imo