I have a NA OZ-Rally 5speed Lancer with bolt ons that I'm trying to re-tune after a few mechanical changes.

The car was tuned after the intake, header and exhaust, maybe not tuned to its full potential but down to under 3 counts of knock through the powerband and the correct 12.5 AFR. Was doing good with little to no issues.

I then did a bunch of random stuff with several different mafs, evo roms, some tephra conversions, and evo throttle body and it threw the car all out of wack. Serious idle and stalling issues, no start issues, and all sorts of random stuff. So i cleaned it all up, worked through the issues one by one and i got everything back to a stable state that i can start trying to tune again.

So after all that i now have a 501 maf and scalings, a random issue with my rear O2 sensor ill have to correct in the soon future, back on a Non-Tephra Stock Lancer Rom, Evo Throttle Body matched to a stock Lancer intake manifold. I still had some serious idle issues and found the exterior manifold solenoids to be at fault so EGR disabled and lines vacuum caped (my 10 vacuum crappy idle became a 22 vacuum stable idle with a rare 200rpm surge after warm up that comes and goes).


I moved on to the tune and did some brief logs and i'm getting some odd results. On my first tune my load never went above 94 and my new load is into the 140's. Mind you, the stock lancer maps only go to 100. I can rescale the maps but i wanted some input before doing so because the high load doesn't seem correct. Secondly, right around the 3.7k - 4.2k rpm range i am seeing this high load, high air flow into the 700's, 10afr, 0 knock, and some serious falling on its face effects. (The high and low octane maps are the same for tuning purposes to void out the rear o2 issue).

I know the fuel and timing all need to be adjusted due to the maf changes but this particular area is not being effected by fuel and timing map changes and im sure its due to maf scaling or smoothing to some effect. So before i progress i wanted some opinions and maybe a hand getting this straight so i can move on to the next step in the tuning process.


Heres a link to my ROM: ROM L4R _LancerOZ_2012.08.15_001

and the below attachment is the log.

 

When you increase MAF size, the load range will increase. That's why after the new MAF you see different normal loads. Also that's throwing off your afrs, making the car go super rich, and falling on it's face.

 

As long as its normal that's fine. I can just rescale the load on my fuel/timing maps to cover the new range. Unless theres some sort of way to scale the maf back into a 100 load range?

As for my rough spot where things go a little nuts, what's the best way to correct this becouse normal fuel adjustments are not gonna fix it. Gonna be a 16 afr in a cell surrounded by 11.5's and such. Edit: Ill try a bit more timing in the area of the problem to see what that does for me maybe.

 

I upped the timing a bit in the problem area and didn't see any change. I didn't push it but a few more degree's and may try more on the next log but i keep seeing this same issue on every Log. I have the maf load scaled down now so im only seeing 108 load at peak instead of 145 load like i was last night but at 4000RPM it keeps going crazy and then quickly recovers again.

The afr drops to super rich and it falls on its face. I don't see a change in timing in the area, the load jumps up crazily and beyond where it should be and the maf airflow hz go crazy but after 4k i see the same airflow's and no issues. The big constant is that it happens at 4k full throttle every time. Is there a transition map i'm missing or enrichment map to fix this?


Happens every time... (I cant move on with the tune until i solve this hiccup.)

 

I nearly doubled the timing in the problem area and still no change of afr, load or knock readings.

 

Getting no love on this... :'(

 

Wait, let me try to understand what you are doing. Are you using an evo rom now or lancer rom?

Do you have resolution for the 145 loads or have you not rescaled yet?

 

Im on my Lancer Rom right now. I did it with 100 load and rescaled the top of the map to include a 140 load but saw no change.

My maf maps were changed to the new maf settings, i then converted it to Hz and spent yesterday rescaling it with the help of short and long term fuel trims to better optimize the load.

The big constant is the problem blimp is the RPM. The airflow jumps up to the 700's during the issue but you can see later that the maf again sees 700 at a higher rpm and it handles it fine.

As a side note I honestly don't understand why the load is jumping that high during the blip when compared to the rest of the run's load which never exceeds 109. Where is this random jump to super high load coming from, and why do i only see it at 4K rpm?


Something is happening at 4K rpm and its not my fuel map because no mater what fuel i load into the cell it goes super rich, up to 18 degree's of timing from an original 7 degrees so don't think its the timing map, its not the open loop to close loop transition because i'm long into open loop when this happens, and its not the maf scaling because the airflow logs read good through out the width of the scale when not at 4k rpm.


I'm open to any suggestions or tests that may lead to a cure. I have my money on something simple being the culprit but i cant point it out.

 

Wait, if you're using a straight up Lancer rom that's a problem. If I recall correctly, the stock rom has fuel, and load limits. Load being a 100 limit. I think that's may be the reason why it's doing weird things like not going past 100 load. (Not sure if a na Lancer can even hassle that hard.) There are many draw backs to the lancer rom. Low resolution, fuel cut, load cut, no knock light... The list can go on.

Since the ecu extrapolates numbers its missing maybe that's the point where the ecu wants to keep pushing but no room to move. Don't quote me but I honestly think you may be running into this. When the early turbo guys trying MAF scaling to get rich because of fuel limits they were definitely running into this problem.

Here's an idea to try, flash big maps with your timing and all and see if things go weird like they are now. Yes, you will throw an automatic transmission code but I'd say it's easier to edit that out than work with that lame lancer rom.

 

Pretty sure the limit was 120 load and i mean real load not the calculated thing your using now which is generally off by quite a bit. Fuel duty had a similiar hitch in it only going to like 70% or something then capping out.

I'm not sure why he hasn't just used an evo rom but yes mine would work in a manual too. The all circuit bypass code should probably remove the cel too.

 

Ok, so to give it a try i put an Evo Tephra rom back on the car. I built a new one from scratch to ensure i didn't change anything in the previous tests.

The start up idle was a little screwy but ill play with that later and after my runs i did get some of the notorious "Throttle Hang Up" which had the car stuck at 5K rpm permanently until i re-engaged the car into gear (as i was finishing the pull i just tossed it into neutral and when i did the car stayed stuck at 5K till i slowed down and put it back into 1st gear).

Now back to the problem at hand... with tephra i was able to see 1byte load which is a better representation of the correct load. And with STOCK 501 MAF SCALING i still ran into the same issue. At 4000k rpm the car goes super rich and falls on its face. The load through out the run does not go over 100 load except in this one area where i spikes to 118. It seems that anytime the car is over 100 load theres an issue. I have the large maps with tephra that go into the 350 load range and i have it setup that anything at or over 100 load is the same settings as the 100 load column. Basicly if anything reads over 100 load it should act like its in the 100 load column, it doesn't but that's how i have the map setup.


As you can see, my fuel maps are out of wack and im getting 27 counts of knock again. I'm hoping its "not enough timing" knock because i cant really see how my timing can get any lower, i had to drop it a bit in the first place to remove the factory perma knock. This is also the same timing i had on my first GOOD RUNNING tune self converted to the larger tephra maps. That or the tephra knock maps are causing me to see a lot more knock then whats really there but if that was the case you guys would have made not of that already i hope.

Take a look at the same issue here on an evo tephra rom. I'm gonna correct the fuel and timing a bit and see if i can clean it up so that i have a better log to show whats happening.

 

Corrected the fuel maps, dropped the timing until it hit 0 and no change. Crap loads of random knock and, and still falling on its face at 4k rpm.

What a nightmare... i have some 50+ runs up and down the street and getting no where fast, pun intended.

 

Theres just too many issues with running the tephra map, so went back to a Lancer Rom, and put the stock 602 Maf back on the car. It doesn't fall on its face anymore but I can still see the 4000 rpm issue. The car is richer 80 load to 100 load at 4000 rpm no mater what i do. You dont feel the effects as hard with the smaller maf but its still there.

I really don't want to be stuck with a 2in opening for a maf, i can literally see the car choking on it. But with out some sort of insight on whats causing this craziness what is my option. No mater the rom, no mater the maf, its still there and i just don't see how something mechanical can effect the car at 4000 rpm full throttle and no where else. Partial throttle and its fine, under 3900 rpm and over 4100 rpm and its fine, i just don't get it.

 

Even stranger.... the same hiccup is on the 100% stock ignition map. What causes it, how do i fix it and why am i feeling it so hard on my car?

 

I would stick with the tephra map. The car is going to dump lots of fuel to try and save itself with knock counts that high period.

If your confident your not hearing knock like stepping on rice krispies kind of sound then there is a strong change your getting vibration like a rattle in the installed parts and the knock sensor is going crazy with it.

Also what injectors do you have and whats their scaling? There is also the possibility you have larger injectors than you think and it will go super rich if its scaled too small.