I really appreciate the input! Actually that makes total sense, i dont currently have a BOV.... it just pushes back through the blades and makes cool noises! Wow... i think thats 100% whats going on actually... cause when its surging its making all kinds of flutter noises, building boost at idle, then not! it would fuck everything up! Soooo is my best bet to add a BOV? or could i switch the maf too the turbo inlet?
Hard to believe you don't have a BOV and even harder to believe anyone helping you hasn't questioned that. You absolutely need a BOV and you probably need to move the MAF into a larger tube. That'll be the easiest way to get it where it needs to be tune wise. You basically need to put the MAF table back to stock and configure the intake until it's close to the stock numbers. Reverse engineer it.
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Yeah John. What the heck, unbelievable. I can't believe that's even a possibility. A blow off valve isnt always used in a turbo set up. Didn't you say you pulled it off an edge or some other Ford vehicle? Would be pretty believable to assume the system is in proper working condition.
These logs from a day ago still look the same as three weeks ago. The MAF is reporting 300 microseconds, when it should be more near 500 microseconds. AS far as I recall you are using a stock housing so the transfer shouldnt be crazy far off in these lower airflow regions. This reported amount of air at 300 uS is putting you at over 1.0 load in idle conditions. Stuck BOV or no BOV can cause strange things, but probably not this.
In a condition where it should be flooded with fuel in OL, when it goes into CL I would expect it to pull fuel out, but instead it begins to attempt to add even more fuel like 50% before dying.
Actual fuel pressures are reaching target fuel pressures. This is DI so you probably didnt mess with swapping out injectors.
How/ where did you install your O2 sensor(s) in the hot side of this turbo kit? Catalytic converters still in the mix? If it wasnt a bad MAF sensor thats the next sensor I would be looking into. Do 2012 focus even come with widebands or just narrow?
I feel like HPT scanner isnt mapped right for your front O2 sensor. Its always around 1.2, then 0 when the engine is in OL. Thats not typical for a WB reading lambda. I would try to scan it using another software like SCT or PCMtec and see what those logs channels say.
Try adding some of these voltage channels to the next log.
Screenshot 2024-02-28 192557.png
Last edited by murfie; 02-28-2024 at 11:30 PM.
No converters and it was a brand new 02 sensor about a month ago! Its in a 3inch down pipe and probably 12 inches from the outlet of the turbo! I loaded the stock tune and took a log, it shows .3 airload for idle. So i took another log with my current tune file and it shows around 1.0 airload at idle... why would there be a change in the airload its reading with just a tune change?
Last edited by TireJohn; 03-11-2024 at 07:10 PM.
The air load changing is going to be from something physical like the BOV I believe you installed. The tune isn't going to change air load, only desired air load.
You can change load with changing the MAF transfer or the injector data. What Im worried about is if your O2 sensor was giving you bad fuel trim data and you entered it into the MAF transfer. Im seeing a 75-95% increase in the idle period range(550-350us) of the MAF between your two tunes.
That much of a change, especially if you are using the stock MAF housing should not be needed. Plus it didnt seem to make a difference as its still asking for 50% more increase, just seems like HPT is not reporting correctly, or you have a bad sensor giving bad data.
airload times engine displacement(0.00135LB) you get per cylinder airmass. multiply that by 2 intaking cyclinders per revolution for a 4cylinder. multiply that by RPM and you get lb/min
reverse this and:
For a 4 cyclinder it would be MAF (lb/min) divided by RPM divided by 2 cyclinder intakes / revolution divided by engine displacement you get airload.
I ended up having a bad 02 sensor, once i replaced it everything was alooot better! I installed a boomba BOV aswell! Right now idle is pretty good but im getting a little surging at part throttle. Mostly stock tune seems to work the best down low... can someone try theyre hand at making some changes?
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