Mag's OSE 12P Thread

[mag]

VL400 was it a holiday or work, either way hope it was successfull. Thanks for taking the trouble to investigate my problem.

Happy that 2 bar MAP voltage scaling is ok, my logging data confirms that the MAP values being used by the bin, at least at the point where the ALDL reads, are correct. My problem appears to centre around what the 2 bar $12P program does when the MAP values apprioach & then exceed 60kPa. My bin also has AFR of 14.7 up to 80kPa yet the AFR dives to 12/13 when above 60kPa. I cannot even hazzard a guess at where it is getting the AFR from.

Clutching at straws, I am running the last of the developmental versions of $12P but believe this is the same as the public realease version. As the 1 bar setup works ok in my version of $12P, I have dicounted a corrupt file, or is it possible that the 2 bar code within the $12P could be corrupt & the 1 bar code ok.

In desparation, I have ordered a GM 2 bar MAP to test against my DIY one, but do not believe this is the solution as the voltage from my DIY appear correct from the logged data.

[VL400]

Got a log of it doing that?? Whats the baro measurement when its not getting the correct AFR??

[mag]

Any MAP value approaching 60kPa starts to shift the AFR down & once it reaches 60kPa it takes a dive. Also, abrupt throttle changes cause a dip in the AFR. May have already attached these logs earlier in post but save you having to search here thay are. They are for the same journey give or take driving conditions/delays etc.

[delcowizzid]

i reckon the dodgy map has a lot to do with it it hits 2.75 volts when it changes to 13.3:1 2.75V is about 118kpa on a gm 2bar map sensor looks like the alternator is toast barely pulling 13v

[Holden202T]

well i can tell you now, that 2 bar log is not running in 2 bar mode ...

do you have a seperate tp5 adx thats setup for 2 bar ? you can't use the same adx for 1 and 2 bar .... hense why the scanner pro adx's attached to the $12P thread have different ones for 1,2 and 3 bar!

[VL400]

Adding to what holden202 has pointed out with the ADX files, you have a baro of 67kPa .. thats why your getting the strange results.

In the log you never give it more than 30% throttle so its not resetting to 100kPa - why its at 67kPa I cant tell from the short log. Can you get a log from startup and until it changes??

[Jayme]

was gonna say, that was some strange shit in that log, whats wrong with your right foot mag, holy grandpa driver batman. give it some stick once in a while lol.
on top of that, I have just noticed, even from my own logs - the MAP voltage seems to be incorrect in 2 bar mode, I mean it shows 4.61V as 97kpa, and I had a 2 bar map sensor on it... that MAP voltage is the same between the 1 and 2 bar defs too. its like its scaled to 0-100kpa no matter what..

[mag]

have checked the battery voltage to the ecu & it is 14 volts. the low battery volts reading in the logs is caused by a scaling error in the resistors on the ecu PCB that feed the ecu a/d converter. changing the surface mount resistors is too much trouble, could change the adx coversion equation to get a correct reading but this would not change the value used by the program. small error should not cause significant adverse effect.

with regard to the 1/2 bar adx issue, I thought the adx is only a means for presenting ALDL info. if so & you only consider the target AFR info, whether it is a 1 bar or 2 bar adx should make no difference. if the 2 bar bin is functioning ok & the input sensor data is good what is causingthe crazy target AFR numbers under load. the MAP values for the 2 bar log at first glance are a bit odd because i did not change the 2 bar adx MAP conversion equation but MAP voltage & scaled MAP values are what I would to expect from good 2 bar MAP sensor. so if MAP data is good & only bin change is selection of 2 bar mode, why the crazy target AFR which coincides with MAP>60kPA & poor acceleration. cruise performance is ok with MAP<60kPA & steady 14.7 target AFR, as recorded in the log.

[VL400]

on top of that, I have just noticed, even from my own logs - the MAP voltage seems to be incorrect in 2 bar mode, I mean it shows 4.61V as 97kpa, and I had a 2 bar map sensor on it... that MAP voltage is the same between the 1 and 2 bar defs too. its like its scaled to 0-100kpa no matter what..

Yep, the value your looking at is a scaled value. 4.61v = 97kPa when using a 1 bar sensor. The code reads the MAP sensor voltage and saves the actual value for all things that have a boost table. It then converts this actual value into the 1 bar equivalent for all items that have just 20-100kPa tables and saves that as the scaled value. Its done this way to keep the code easier to work with when having multiple MAP sensor types.

have checked the battery voltage to the ecu & it is 14 volts. the low battery volts reading in the logs is caused by a scaling error in the resistors on the ecu PCB that feed the ecu a/d converter. changing the surface mount resistors is too much trouble, could change the adx coversion equation to get a correct reading but this would not change the value used by the program. small error should not cause significant adverse effect.

with regard to the 1/2 bar adx issue, I thought the adx is only a means for presenting ALDL info. if so & you only consider the target AFR info, whether it is a 1 bar or 2 bar adx should make no difference. if the 2 bar bin is functioning ok & the input sensor data is good what is causingthe crazy target AFR numbers under load. the MAP values for the 2 bar log at first glance are a bit odd because i did not change the 2 bar adx MAP conversion equation but MAP voltage & scaled MAP values are what I would to expect from good 2 bar MAP sensor. so if MAP data is good & only bin change is selection of 2 bar mode, why the crazy target AFR which coincides with MAP>60kPA & poor acceleration. cruise performance is ok with MAP<60kPA & steady 14.7 target AFR, as recorded in the log.

Your problem is the baro, get a log starting from before you even start the car and then also with some driving around under mixed loads. The target AFR uses the baro to have an altitude referenced lookup, so with a 67kPa baro it will be using the 100kPa column when the MAP says 67kPa.

Just a side note I have found that the battery voltage on the ECMs I have tested are pretty much spot on, always within a tenth of whats at the power feed to the ECM. There will be a voltage drop from the battery to ECM.

[mag]

battery voltage to the ecu is ok, my problem is that the resistor divder on the ecu pcb, that scales the battery voltage to the a/d converted chip appears to have drifted & consequently the value read by the a/d converter is incorrect.

if baro value is cause of my problem with 2 bar setup & the only hardware change from 1 bar to 2 bar is MAP sensor why do I not have a problem with a 1 bar setup.