Joined: 18 Jul 2017
|Posted: Fri Sep 15, 2017 11:41 am Post subject:
|olafu wrote: |
|What BIN number you are using?
I did some research about that at last year with 623 BIN. Unfortunately seems like there is no IAT correction for TPS based "Alpha-N" limp map.
BUT there is somekind "knock prevention map" or something at E044. It is air temp and engine coolant temp dependent 3x4 map. It starts from E039 like this "D7 03 0D 0E 2D D3 04 14..." and map data starts at E044. D3 is IAT and D7 is CLT.
As higher as map value is, it's reducing ignition advance and adds fuelling. Original map has positive coefficient to IAT and CLT.
When i said there is no IAT correction, i mean, i tried to fill with "00" whole map, and replaced IAT sensor to adjustable resistor. If whole map was "00" or filled something else "fixed" value, there was nothing changes in injector open time altough i tried to change "IAT" value by potentiometer. So, with this information, there is no other things to adjust injection time by IAT.
So, was that map whatever, it's effect to fuelling is INVERTED of real IAT correction, and so it GAINS effect of IAT to AFR. Try to clear what value ECU reads in "normal conditions", fill whole map by that and check what happens. You can also try to use this map for real IAT correction, but you must remember this map also effects to ignition advance.
In case of 8.5ms "Basic load value" i tried to add +40 (dec value) to every cells in this map, and that reduces about 25 crankshaft degrees of ignition advance, and increases injection time by 6ms. Unfortunately i didn't write RPM's in my notes.
So, try to fill whole map by fixed "normal conditions" value, it would help your AFR problem, but remember, it can propably change your ignition advance.
Sorry about my bad english.
EDIT: There is propably usable 8x5 map at D7E5. It starts from D7D4 like this: "CE 08 02 08 0C 19 19 19 32 6A D3 05 28 28 28 28..." and map data starts at D7E5. This is originally filled with 128 (dec).
This is translated direct copy from my notes:
0xD7E5 table - original value 128dec at every cells. Measured first at 5900rpm:
"Load" is set to produce 6ms real injection time:
Decreasing cell value by 100 reduces injection time from 6ms to 1.7ms.
Increasing cell value by 100 increases injection time from 6ms to 10ms.
"Load" is set to produce 10ms real injection time:
Decreasing cell value by 100 reduces injection time from 10ms to 2.5ms.
Increasing cell value by 100 increases injection time from 10ms to 17.5ms.
"Load" is set to produce 19ms real injection time:
Decreasing cell value by 100 reduces injection time from 19ms to 3.7ms.
RPM value changed to 2900rpm from 5900:
"Load" is set to produce 19.4ms real injection time:
Reducing cell value by 100 reduces injection time from 19.4ms to 4.7ms.
"Load" is set to produce 10.2ms real injection time:
Increasing cell value by 100 increases injection time from 10.2ms to 17.9ms.
Decreasing cell value by 100 decreases injection time from 10.2ms to 2.7ms.
Injection time is injector pulse width, measured by scopemeter.
Tests are done by running ecu out of the car with only crank trigger signal, without cam signal. Crank signals was produced by playing crank rotation sample in loop from a computer through soundcard. Main sensors was replaced by adjustable resistors or voltage dividers. Coils and injectors was replaced by dummy loads.
"LOAD" signal was measured by Bosch KTS test equipment.
You can also try to change MAP descriptors. I did some tests by changing map descriptors by step to step from 00 to FF. Some "low value" descriptors was kicked ecu to run weird and messy, looks like it's resetting or crashing continuously. You can change any map to read any value from these descriptor values. I think these descriptors are RAM addresses what map research routine reads, so it's more or less a lottery to change the descriptor values, because these can carry unfinished data between different routines.
As you propably knew, you can also resize every map axis by reducing it's size in X axis and increasing it's size in Y axis, and vice versa, but it means you must re calculate all map axis and map data by hand, and new map cannot be bigger than original.
There is "MAP address table" in end of data section of ROM (as you know), wich offers nearly free hands to do what you ever want, but i don't know how much these can be tamper without hidden fatal problems.
I use a 403 DME with Bin number 950.
I see exactly what is the 8x5 table you tell in your edit This must be the first table I tell in my first post, this one:
I was quite sure this was an IAT fuel correction but when tracing I'm always in the 60°C column, at different temperatures. The sensor seems to be good because the resistance changes with temperature, I need to verify if wiring is ok. I also wanted to put a variable resistor in place of the sensor to verify if the column change by varying resistance.
For changing table size it should be OK since I did it on the alpha N table to make it 16x16, I talked about that in another thread if you're interested to talk about it : http://tunerpro.net/forum/viewtopic.php?t=4419
The big problem is that I'm not sure what really is the IAT descriptor in this DME