So I've diagnosed an issue particularly with VE. MAF doesn't seem so effected.
From startup, after driving for say 30-40 minutes when the cars at full temperature ........ The AFR swings massively once the engines oil temp finally climbs up above like 86 degree's.......
at say 84 degree's it may range in the 14.7 mark, 87 it's running 5.3's, 89'c 15.7's, 91-94..... up into the 16's.......
I've been looking at different compensating methods via transient impact and evap tables....... what happens with the merging of the maf and the ve correction factors in a mixed mode situation and so on.
Now I haven't found a real full proof way around controlling it....... Does any of the more technical tuners have any other idea's here. I feel like i'm chasing my tail. The guy I had run a mafless tune up the dyno I dont think had a clue about this wild AFR issue.....
It makes it rather difficult to tune at present, so what I'm looking for is matching the closest MAF or VE tune against the entire temperate board and then focusing on bringing each area to where the car idealy wants it but i keep hitting stumbling blocks......... eg. sometimes I might change something then the car wont run properly, claiming some weird TPS issue or something....... it seems like the Gen4's a bloody picky as hell.
I cant just 'tune VE and MAF' and have it work. As it has a 20% swing ........ no matter virtually what I throw at it, I keep getting mixed results .......
Idealy the end goal is to archive where the AFR's should be with what the car requests...... It's driving me nuts.
Outside the transient tables, maf and VE.......... how else can I control it. Some things may bring the AFR's more inline but then effect drivabily due to swings either direction with EVAP or Transients etc......
I looked at the manifold air temps, and all the various various with IVT etc to try and pinpoint a particular location to control it ...... I figure if I can get VE inline across the board and just retouch the maf it will work correctly in mixed mode closed loop.
I've been at this a while now and I've only just worked out this massive swing and the fact it seems to correlate with oil temp ........ in particular. I did a standing IAT AFR test...... and it was fine, didn't get effected until over 54'c......
So I've done my homework....... and now I'm looking at ways of nailing down the issue. Ultimately if there was a OIL TEMP multiplier for the custom OS for VE I'd have it sorted immediately but there's not.
All my issues cant link to things I can control........ My only option is to use 'everything' to sort this out........ a little on each....... seems rather time consuming.
A little transient impact/evap..... a little manifold air temp control, a little charge temp/bias adjustment, a little this that and the other.
I can see why tuners go for 'maf' as it's the closest and most consistant.......... not to mention easiest....... but the maf cant deal with certain throttle response....... and hence this is where VE makes the magic....... so idealy i'm trying to archive how the car was intended to be used...... a mixed setup.
Seems like alot of effort....... but I'd like to solve it, as it's bugging the hell out of me.