Supercharged Lean Out Issues

Any update @snivilous ?

 

Haven't seen the truck yet, still traveling for work. Hoping to get in it this week and start datalogging and see what I can find. Will keep this updated as I know

 

So non-update.... Update? Went through a cluster fuck of getting the truck geared (5.29) but got it back last week, just got home from my first trip down the hill towing the can am and same exact shit happened coming home, maybe even worse than before. Out of curiosity I pulled up engine load on my phone, and (especially in 5th gear) I lean out hardcore in the 80-90% load range, sometimes in the 75-95% range but if I drop to 70% load the afr goes back to holding 14.7. I'm not sure what engine load from the OBD2 is actually representing (either I don't understand it well enough, or the technical definition is different) since I can easily hit 100% load and still have a lot more pedal left to give it (and boost). Regardless, engine load seems to be a metric that was reliably bracketing when I could expect to see the AFR lean out. Course that didn't help much when cruising was almost always in that 80% range climbing a hill.

I can still floor it and afr richens out, and below 70% load it never leans out.... So it has the feeling that it's a tune issue. I'd like to try and replicate it on the road without a trailer now that I have some idea of what variable to shoot for to make it repeatable (then I wouldn't have to tow a trailer up a mountain to test ideas) or find a dyno. I'm leaving on Monday to drive to Colorado for the week for work, and will see if I can figure anything out on that drive. Once I get back I'm thinking of talking to OV Tune and see what he says, and also datalog my next tow trip.

This was a long post concluding nothing, but I'm beginning to hone in on the specifics of when it's occuring which is progress

 

@snivilous Does Torque Pro have the "loop status" PID programmed into it so you can observe whether the ECU is operating in closed/open loop mode? I'm wondering if you are running into a situation where you're in open loop enrichment but there is not enough fuel being added, and thus you're seeing those lean conditions.

80-90% load range is most likely in the open loop range, but that may not necessarily be correct on the OVtuned provided tunes.... the other big thing that stands out is the replacement of your air intake, I believe the open loop enrichment relies on the MAF sensor data (amongst other sensors) as inputs to determine the correct amount of fuel to inject, and if your air intake is different enough that your MAF readings are slightly different, this could maybe be why you're seeing these conditions.

 

I'm not sure, I'll look into that. I went over all the hoses again last week, drove to Colorado, everything seemed fine and then on Saturday towed the trailer and same issue again. My next move was gonna be to swap the old intake back over and see what that does. The injectors all seem to be seated, all the hoses seem fine (I'm gonna replace the PCV and hose since it seems to be weeping), the new intake has all the correct through ports, throttle body is fully seated, etc. Seems odd the Air Raid would be happier than the Magnuson intake, but if it's not that it'd seem like a hose is compromised or something happened when I installed the blower. The fact I can only get a reliable reading while towing a trailer doesn't help speed things up either (I was able to make it lean out coming back from Colorado on some passes, but it's pretty hit or miss and hard to tell if it's staying leaned out for a long period).

 

Correct me if I'm wrong, but wasn't the process of having the OV Tune setup for your truck that Mat provided a base tune, then you go out and do a couple runs while performing data logging at which point he's able to take the logged data and tweak the tune to bring your power back?

The fact that you're saying your AFR is plenty rich when under WOT leads me to think it's not a pinched hose or anything like that. Just to confirm, the boost ports on your supercharger are all plugged/capped, correct?

How are you measuring your AFR?

 

While yes on the OVT part, I never actually did that. The whole process seemed like a pain in the ass, and the truck was running fine so I never had him really tweak it. I'm hoping with his new tuning suite (and it being 18 months later) that his latest base supercharger tune is just an updated version of the file I already have (which I've always been happy with). I'm not worried about making a lot of power if the tune is safe.

And yes, all the supercharger ports are going off to other things. There's the three ports off the blower (one to brake booster, one to PCV, and whatever the other one is to), then the supercharger boost sensor port in the back that I have going to a stand alone wideband/boost gauge in the truck, and then there's the two ports going into the intake tube (one to fuel pressure regulator, and other to valve covers I think?). I've done plenty of pulls lately, and the truck will richen out at certain points and at WOT will hold steady at 11:1 through shifting at redline, so I don't think it's a fuel flow issue either.

I have the Torque app monitoring AFR as well as attempted AFR (so I know what the truck wants to be at), and the trucks narrowband is backed up and almost always dead nuts with my wideband.

Now to go into more more recent weirdness. So after I towed my trailer a week ago and found that at 80%+ load it starts leaning out, I drove up and down the highway and was able to replicate the lean out with no trailer in the same load regime. I climbed through the engine bay, checked all the fuel fittings, checked and pressed on the injector plugs, put new/better hose clamps on anything that seemed weird (namely the brake booster side hose, and the intake tube side valve cover hose didn't have clamps but they were both tight, but added clamps anyways), and retorqued the throttle body. I tried to replicate the lean out and could not, and on my whole way to Colorado on Monday I could not get it to lean out, and I had long stretches over passes where I'd have cruise at 70 and set it to 5th gear so load was at 80-90% and it would not lean out. Seemed fine. Then on the drive back from Colorado, on some passes (going opposite direction now) it would lean out, and then this weekend towing the trailer it was doing it again. So I don't know if I actually fixed anything in the first place (and if I did, and it became unfixed, I have no idea what I would've done). Like I said, the PCV is the only hose I haven't replaced the clamps on purely since it's a bitch to get to. I'm thinking reclamp/replace the PCV, swap the Air Raid back on, and check torque on all the supercharger mounting bolts. If that doesn't fix it, I'm at a loss besides tuning it. I posted on the VF Tuner forum and the main guy there didn't think it was a tuning issue, which I'm 50/50 in agreement on since a lot changed, but also I'm making about the same boost as I was before getting the supercharger rebuilt so it doesn't seem to be a big enough airflow difference the tune couldn't keep up.

Excuse the long post, just trying to put every possible glean of information and data I can find in case that points out the obvious to someone.

 

Not much help. The trucks AFR sensors are wideband, was going to add one till I stumbled across that.

 

I was under the impression that Mat was providing "converted" vft files (along with a corresponding master key/unlock credits) to existing OVTune users. Have you been able to look at the data within the tune file yet?

I believe the third hose of the three on the pre-rotor side of the supercharger goes to the VSV solenoid... are you sure that the other end of the VSV solenoid is connected properly (and that it is closed as it should be by default)? I don't know when the ECM decides to trigger the VSV solenoid but I wonder if it's acting like an air leak.

@Vizsla It is my understanding that the trucks have "wideband" sensors but that they do have a lower range where they no longer read... I could be wrong though.

 

Touche, I don't know what's considered a wideband but my standalone reads way further than the stock one does (or what Torque Pro reads) which maxes out at 12-18 iirc, and the truck will richen out way past what the truck will read to.

You are correct, Mat is converting files to vft, since my tune is effectively the base OV Tune there's nothing that needs to be converted. I'm just one of the lucky few where VFT won't currently flash my truck for whatever reason, which is what I'm waiting to be patched so I can flash the VFT base tune and tweak on that and see if any changes are made.

Ah I see, well all the VSV stuff seems to be hooked up correctly. Maybe I'll check all those connections and reclamp all of them too. It's too bad there isn't a brand new hose kit I could buy and weed out any holes in any of the lines.

 

Does this mean that you already have the VFT license and can examine the tune? If so, you should be able to look in it to see if you would be running in open loop at that point...

The other end of the VSV solenoid goes to the charcoal canister above the fuel tank from my research, which is quite a bit of hose. You could potentially plug it, but it's probably easier to smoke test the hose/solenoid to see if there is a potential leak from this.

Just to confirm,


you have this barb hooked to your boost gauge, where is


this barb hooked up to?

 

You're probably correct on the first part, I'll snoop around.

I haven't smoke tested anything, I've tried spraying fluids at the hose junctions and seeing if there was a change in idle or any variables and haven't found anything.

And yes, first port is to boost gauge. Second one isn't a port, it's just a stud.

 

Makes sense. I've found pictures online of the TRD supercharger with plugs over it so I wasn't sure, just wanted to check. I know that on some superchargers there is a barb/port there that has to be plugged as well, but it doesn't look like yours is machined for it. On the Magnuson it is just a set screw/plug.

 

The tune that @snivilous is running is in .p5f format and cannot be read by the vF Tuner software. Only .vft/.vfc files can be read, that's why some are asking for conversions. At some point all .p5f files with be converted to .vft/.vfc.

Additional: I had to look it up. The stock A/F ratio sensor won't read below 12.0:1.

 

I understand this, but @snivilous is saying that the base p5f that was provided by Mat and the "supercharged "calibration that comes with vfTuner are very similar... although thinking about it, the Toyota Flash Tool is able to flash `.vft` files, so maybe you could try using that instead of the vfTuner built-in flash tool....

also, are you absolutely sure they are the same? From my understanding, the files that come in the vfTuner are "stock" calibrations, which would be different from the one Mat was originally providing as base tunes for his enhancement...

 

They should be the same.

I think I recall reading this. I will have to try this for a test of something unrelated that I'm looking at with my tunes.

Unknown.

 

@snivilous are you still running that smaller pulley?

 

Yup, been running it as long as I've had the blower

 

I guess I had assumed the vft files in the supercharged calibration folder had any bugs worked out, and were "stock" and essentially had all the normal shit turned on and tuned for a supercharged truck. I applied all my credits to the base supercharged calibration for my ecu, though if that calibration is different than the one I originally have with gearlock and everything then I'll have to get that worked out.

 

Another thought to add to all of this, if the stock sensor can't read below 12:1, then the truck isn't really aware of how much fuel it's dumping when it's going to 11, 10, I've even had in the high 9s. Could that indicate issues with the tune? When I had the TRD tune it'd run in the low 10s/high 9s all day long at WOT, the OVT is a bit more conservative but not by much. Is the truck just blindly injecting a shit load of fuel and making assumptions about the true afr, or is there something else actually reading it? Or does it not even know how much fuel it's injecting and it thinks its at 12:1 and really it's at 10:1? Just food for thought. I emailed Superchargers Online to see if they have flow test results from when they had my injectors and if any of them seemed off.

This whole thing process has been confusing trying to read stuff, most tuning and AFR discussion is about WOT and nothing else.

 

My understanding is that at high load/WOT, the ECU goes from closed loop (where it targets an AFR value) to open loop, using input data such as MAF and temperature to reference against a table but NOT using the O2/AFR sensor to attempt to target a low/rich AFR value. This is what led me to my thinking that your tune is switching to open loop, and subsequently not injecting enough fuel for the given MAF values that the computer is seeing. Of course, this is entirely speculation and I'm only a software engineer in a completely unrelated field who knows very little about actual vehicle performance tuning, but has spent a lot of time reading things on the internet.

 

I have no reason to expect that Mat's "stock" S/C'd files are any different than the TRD S/C'd tunes (no GL, etc.), just converted format. I could most certainly be wrong though.

Now that @Oats87 has remined me that the older Flash Tool can flash .vft/.vfc files, I'd like to experiment to "feel" the difference in the progression of the tunes I have from Mat. Free time is at a premium right now though...maybe the weekend.

 

Guess I said that wrong or something... I don’t doubt the factory wideband has less range if it’s not useful/needed.

WOT goes rich, how much I don’t know obviously. PE is about adding fuel to cool for longevity, past ideal AFR.

 

@snivilous I was thinking about this some more, and had a thought -- you said that you changed from the "Air Raid" intake to the Magnuson-provided intake. I may be wrong about this, but it is my understanding that the MAF tube diameter is bigger on the Magnuson-provided intake to allow for MAF scaling, if this is the case, your "Air Raid" intake would be providing "stock" MAF flow rates, and the Magnuson air box lid would theoretically provide lower flow rates, hence leading to being lower on the table and not injecting enough fuel, especially if you're in the enrichment (open loop) portion of the map. Have you been able to swap the original intake you had back onto the truck?

EDIT: Yep, the more reading I do into this, it looks like the TRD/Magnuson air box lid has a 98 mm diameter, whereas stock (and most N/A aftermarket intakes) is 91 mm...

 

I haven't swapped it back yet, I plan to this weekend before I hook up the trailer and see what happens. I like your theory, however it seems like the tune should be setup for the larger intake diameter, or at least be able to compensate for it since it's the one that should've been on the supercharger originally. It seems weird the tune/ecu would get tripped up with going to the "correct" intake? Though I guess that's assuming everything was correct from the get go, maybe the air raid was providing faulty numbers that were actually correcting the afr to richen out...

 

MAKING PROGRESS! Huge thanks to @Oats87 for the idea and what he researched. I swapped intakes yesterday, and stuck a tape measure through the MAF port and roughly measured 3.50" on the Air Raid tube and 3.75" on the Magnuson (additionally, the big nipple goes before the MAF on the Air Raid and after it on the Magnuson if that matters). I didn't change anything else, didn't even reset the ecu or anything, and today loaded up the trailer for 150+ miles and it never once leaned out incorrectly. Now there is a grain of salt, I wasn't driving the same path I have the last few times, but all the miles were through the mountains so lots of extended high load sections in every gear and speed, so it should be a fair comparison to the big hill I was seeing the lean outs on before.

Interestingly too, and I guess to be expected, I was actually seeing richer AFRs than usual. Even before making boost it'd be dropping into the 13s, even 12s at times, where as before it seemed pretty locked in to 14.7 unless I really got on it. To further support the intake diameter theory, which I hadn't thought about before: the TRD tune AND original OV Tune both ran really rich, which I never thought anything of, but I've always had the Air Raid (used supercharger, and truck came with the Air Raid so I made the two work together). I actually had talked to OV Tune about leaning out my original tune right after I got it, since one thing I wanted was to get away from the very rich TRD tune. It would make total sense that the TRD tune and first OV Tune were setup for the Magnuson intake, and my intake was seeing higher intake velocity so ran extra rich. OV "corrected" that (as much as possible without datalogging and me giving him some information), so the OV Tune got leaned out and then I got the correct supercharger intake and now that same tune is too lean when originally it wouldve been correct. All the pieces line up, why all my tunes were too rich and then why the not rich tune is suddenly too lean, and the only "big" change was the intake area at the MAF increased by ~15%! In conclusion, I think @Oats87 is on the money and the tune is indeed off because of the different intakes. I'll keep the Air Raid on for now and see how it compares and eventually do a pull with the trailer up the "baseline hill" to confirm its not leaning out, but the truck seems richer and similar afr to what I remember already.