Myszkewicz

iTrader: (2)

And yet the Split Second (RRM) piggyback reads and modifies the signal, but displays it as voltage, not frequency. I'm beginning to think it's been that simple all along.

DangerousDan

iTrader: (8)

yeah, but the damn thing won't work like that. there may be a problem with the frequency itself, didn't you say you had an o-scope?

DangerousDan

iTrader: (8)

this is the map I have built. Looks like what is in the split second unit recordings I have

DangerousDan

iTrader: (8)

hahaha, I am closer now. Split second has sworn me to secrecy, and I am not sure it will even matter anyway I will let everyone know if I get the mapecu2 working, and how I did it if so, but I won't be telling anyone anything more about the MAF circuit. sorry guys, but it took three or four emails (and they weren't short emails either) to cajole him into helping me with a competitors unit. needless to say I think I will have to purchase the split second unit anyway, but at least now I will know why.

Myszkewicz

iTrader: (2)

Info or BAN.

DangerousDan

iTrader: (8)

there is a 1k ohm oull up resistor between pin 63 and ground in the ECU. just measured this myself

hackish

A resistor between the MAF signal and ground would be a pulldown resistor not a pullup resistor. Yes the MAF is an analog signal. I'm playing with it right now trying to get a haltech miniceptor working.

-Michael

DangerousDan

iTrader: (8)

ok, pull down resistor. have you gotten it to work yet?

hackish

Yes, I did, in fact your suggestion of a 1k resistor is pretty close to the load the factory ECU puts on it. I suspect they do this for noise immunity and fault detection.

Unfortunately I'm having some trouble because it requires a certain amount of throttle to enter power enrichment mode and less than that throttle causes it to go into boost. I don't mind running a car a little lean under a few PSI but above 5 PSI you definitely need that extra fuel to keep things cool.

I've tried modifying the TPS value but of course this confuses the computer because it throws a TPS CEL as it's a hybrid DBW system (they use a cable to make it feel like a real throttle). I'm going to try patching into the MAP signal to see if they also enable PE mode from the MAP value.

Ultimately I suppose I should try to figure out how to reflash these. I opened the ECU and it's a fairly run of the mill processor so if I had the extra time I'm sure I could get a ROM image and disassemble it.

-Michael

DangerousDan

iTrader: (8)

it would be nice to have reflash capability. I've been trying to get people smarter than me working on this for a long time.

I don't believe the MAP sensor has any affect on the fuel trims. I could not change afr no matter what voltage I put to the sensor.

there is more to the MAF circuit than you have discovered thus far. I'm not sure how much you have talked to haltech about it, but I am sure they would be more than willing to help you get the miniceptor wired up and running 100%.

the MapECU2 has o2 adjust, which lets you offset the o2 sensor voltages so you can tune for turbo without throwing a cel or having the stock ECU try to adjust the fuel trims in closed loop, does the haltech unit have this? short of flashing the ECU you need to be able to trick the ECU into thinking it's running ~stoich in closed loop.

also, the MapECU2 has a tps enrichment table, I think it's 1000 to 10000 rpm in 1000 rpm steps, that it uses to calculate the fuel needed for quick throttle changes.

hackish

Fiddling with the O2 voltage will only help if you can keep the STFT and LTFT's in check but that is generally done through tuning not through O2 foolery unless you wanted to make it think it's running stoich when it isn't. PE mode will by definition disable closed loop operation which is why I'm aiming to make sure it comes on when I need it to. Since we're not changing the displacement or VE characteristics of the engine the TPS enrichment feature you speak of is not of significant benefit.

If I were to embark on developing a reflash then it would require significant time and money investment and I'm not sure there is enough market to recoup the costs.

-Michael

DangerousDan

iTrader: (8)

that's backwards. the o2 sensors are what make the fuel trims change. if you modify the signal you can set the target afr to whatever you want and your fuel trims will be 100%

that's exactly what you need to tune your partial throttle low boost driving

are you talking about when the ECU changes from closed to open loop, or does the miniceptor have an enrichment function that is vs tps?

your trying to tune turbo though aren't you? that means EVERYTHING is different, and when you punch the gas at 4000 rpm from a cruising condition it's pretty likely the stock ECU enrichment will not be able to keep up.

the reflash is *almost* a reality for this ECU, I'm not trying to be an *** or anything but there are many many things you still need to read up on if you think you'd be putting yourself out developing a flash method. almost all the work has been done at this point; the latest opinions are pointing to the ecuflash program not having either the correct init code, or an incorrect address for the init sequence itself.

hackish

Maybe I didn't explain it well but the closed loop operation on most ECUs targets stoich. It does this because that is all it knows. The bosch stuff and a few other ecu manufacturers are different with their latest generation using wideband for closed loop. If you adjust the O2 inputs then you have to do both or you'll be throwing cat inefficiency codes. You can be successful in shifting the entire closed loop mixtures around which doesn't really help. Alternatively if your ECU supposed a translation table you might be able to get it working but you would need to know exactly where each STFT and LTFT cell starts and ends.

I have been keeping an eye on the OpenECU group but they are basing a lot of their assumptions on the outlander turbo that one guy "apparently" reprogrammed. The point is if I spent the time necessary to crack it then it would be a matter of weeks before someone reverse engineered my method and gave it away. That sort of thing doesn't make money.

-Michael

hackish

TPS enrichments are only to combat a sudden change in intake velocity that tends to knock the fuel out of suspension. Turbo or not you're unlikely to be outside the factory parameters. I've tuned a few cars with absolutely no TPS enrichments and the difference of adding them was very subtle.

If you're instead thinking of alpha-n as used for ITB tuning then it's definitely not appropriate for a turbo car as airflow is independant of throttle position as the turbo spools.

DangerousDan

iTrader: (8)

It sounds like you are a businessman, and also that you are going an awful lot on assumption about the openECU progress on the 4g69. and I can tell you that it won't matter if you try and crack it or not, someone will do it for the betterment of the community instead of to make money.

the unit I was referring two will offset your voltages for both o2 sensors, in a large table, mapped against manifold absolute pressure(with either the built in sensor or most popular three wire sensors). you can fine tune your closed loop AFR's using this map and the MAF emulation map without affecting the stock fuel trims at all; the ECU will not be able to see the actual AFR. Instead, it will think it's running stoich. the tps enrichment feature is there if you need it, as are many other features. www.mapecu.org if you are not already familiar with this particular piggyback.

This is the ralliart forum, what does another manufacturers use of a wideband o2 sensor have to do with the RA MAF sensor circuit? it's obvious you have an understanding of cars, but some of the things you are posting either don't apply or only apply in certain situations. the basic net shift o2 adjustment you are inferring from my posts can be easily accomplished with any wideband controllers configurable analog output, such as the LC-1 that I have. what I am actually talking about is likely not possible with your interceptor, and is not possible with the split second units, but is fact with the mapecu2. you can run whatever AFR you want, whenever you want, and still pass inspection if you have the right piggyback. no cel, 100% fuel trims, even catless if you wanted to, although I really frown on that

I encourage you to look into this unit. I will be installing the prototype converter so I can eliminate the maf tomorrow, once I am done testing and report back to performance motor research they are going to pretty it up and offer it for sale to the general public. If you are having AFR problems under boost this is one potential solution for you