Instructions for custom tuning the truck with HPTuners.

Coincidentally, I was considering doing the same thing with what you've shared about how you go about tuning the engine. Maybe test back and forth between what I have for my transmission and stock too.

 

I wired in the Prolink+ to send my PSB-1 AFRs to show in VCM Scanner Chart vs. Time display. Of course I seem to like graphs too. So I tried making up one of those, unsuccessfully. For C vs. T, there is the option for the data to be rendered in AFR Ratio which is of course what I've done. Trying to set up a graph, the only option is to have the data rendered in V, which is fine as color shading can be utilized to give a quick visual reference of rich vs. lean. But....nothing shows in the graph so obviously I have it wrong. So....has anyone else tried constructing a graph for AFRs?

Here's what I have:

 

I don't know what you're saying with all your letters, but this is what I do with the stock narrowbands just to get a quick lay of the land that it's richening out when I want.

'

 

Ya, I don't know what I'm saying when I don't know what I'm saying. Can become a word salad, and salad is worthless.
HA! I got it this time!

 

Does anyone have any theories as to why I might be getting what seems to me to be these random bits of Knock Feedback, as well as the occasional greater ones? Just cruising down the highway. When I'm out trying to fine tune the timing tables, I have to make sure that I'm going through the log and filter out what I might call noise and just making adjustments where it looks like it's legitimate, otherwise I'm thinking that I'm dialing it back way too much, hurting power. In other places of the log, it's as flat as can be. When I had the blower off a few months ago, I made it a point to look at the knock sensors and wires. They looked fine, and I've never had rodent issues.

 

That is weird, I've never seen that on any log. Maybe there's something tapping the engine triggering it?

 

https://youtube.com/shorts/LONT1oboJrs?si=Z3CIx3N62kertEoc

 

Does it occur all the time. Some light reading said loose bolts or loose heat shields shouldn't be picked up by the knock sensor. What fuel are you using? That was one of the suggestions that could cause random noise or detonation being picked up.

 

I went out and did some laps on my nearest test loop as three separate logs. It's not literally all the time, it seems more intermittent. A little blip here and there and sometimes more of a minor spasm. I searched around some using terms like "intermittent/fake/phantom knock feedback" (a lot of Subaru related hits). Some suggested loose items, so I tried hitting some of the rougher spots in the pavement with no correlation. One troubleshooting video attributed a case to clapped out engine mounts. Interestingly, I have solid engine mounts. I have my converter anti-theft plates and they might be doing some sort of weird resonance thing that's traveling to the block via the engine mounts, I guess I could pull those and get a log. That remains a hypothesis. I tried surging the throttle manually to see if it was related to engine load, nothing. Sometimes there's a blip during a slow cruise on a smooth section of pavement. I went through the three logs and dialed back the timing one degree in the cells that showed feedback. I likely won't mess with it until this coming weekend unless something more solid occurs to me. Sometimes I find the strangest anomalies...

 

@Wynnded that's what I found. Subaru tuning sites talking about those anomalies. I wonder if it's present on anyone else's rig with solid engine mounts?

 

I thought of that too. @reywcms is the only one who comes to mind. I think he may have a set, but I don't know if he's installed them yet though.

 

I have them installed as well but I’ve never combed through my logs looking for it. DAP nor 4firemandan that has done some tuning for me has ever mentioned anything about it, but maybe it’s not worth mentioning.

 

Well, I went to HPT forums and looked at most all of the logs posted there in the repository, including the ones that I uploaded, as I've deleted them from my computer. Some logs have the behavior and some do not, so it appears that it's not something to fixate on.

 

Anyone have any thoughts on why my truck won’t go into PE at the TPS% it’s set at in the tune? It’s set for on at 30 off at 25 for the last two files I flashed, and logs on both indicate it doesn’t go into PE until 40% TPS. Is COTS being active somehow to blame? Any ideas are welcome.

 

PE activation isn't measured from TPS, it's degrees of throttle actuation.

So if it's set at 30deg, and the total motion is 86deg then that's really ~35% TPS. And I think those numbers are a bit off, the truck might not look at 0deg as full closed. If it thinks full closed is 6deg open, then that's really 30deg/80deg = ~38% TPS. What you're seeing is normal, my truck is set at 30deg and activates at ~40% TPS too.

 

Thanks for the help! I’ve been getting confused by this very thing as the channels I was using for logging seems to have about 5 different methods of referring to throttle angle and it’s hard to tell what’s what, half of them sound the same. There’s :
Accelerator pedal %, TPS%, accelerator position D (SAE), throttle position (SAE), Relative throttle position (SAE). I mean, what the heck! I started using a different set of channels since. I may try lowering mine a tad more as I’m getting 3psi of boost on certain hills before ever leaving stoich up to that 40% TPS mark. I’d like it to be in the 12s-13s when seeing that bit of boost/high load and low RPM situations.

 

I only look at TPS% personally.

That is one of the logic arguments I have with myself with PE. It'd be nice to do a small enrichment at low boost, like interstate cruising for a hill, but then that's dropping PE up to like 3000rpm and if I floor it from a stop I now want it to dump fuel at low rpm and high boost. The only way to really get around that is trying to manipulate the COTS table like the TRD tune does to give you a more dynamic enrichment versus the on/off of PE.

With that said, high boost doesn't usually = low rpm, and when it does it'd be for a split second so maybe running low PE at low rpm is fine. Despite that I still set PE under the assumption the truck can see full boost at any rpm and hold at that rpm, which isn't realistic but is also conservative so I decide to live with the mpg hit when those hills come up.

 

I also set PE enable/disable to a 2deg spread nowadays. I did do 5deg for a long time, but that's such a large throttle difference (at least at the low throttle levels we're talking about) that the truck would enter PE on the interstate and then just never get out of it, I'd have to turn off cruise control, get it out of PE, turn cruise back on and then it was fine. 5deg at 25-30deg is a good percentage of the total throttle being used. My logic with 2deg is that's enough of a difference that it wont flip flop in/out of PE constantly (like might happen at only 1deg of separation) but is small enough that the truck can easily get out of it when it does accidentally step over the threshold and doesn't need a massive throttle drop to exit PE. Trying to toy that fine line there...

 

I am not making the adjustments by myself in this case, 4firemandan is helping me out since he scaled my MAF a while back. He seems to think we can get it in the 13 AFR range in these situations but I’m not sure how exactly he is accomplishing that. I haven’t really consulted him on this PE thing either yet, just asking questions based on what I saw in my logs vs the tune settings as I try to learn more about it and not bug the crap out of him lol. I know he has of course adjusted the PE settings down gradually, but he has also increased the injector pulse width at varying low/mid range engine load % so maybe that’s how he is getting it to richen up without going full PE dumping AFR into the 10s? I’m just comparing files, maybe he adjusted those things for entirely different reasons. But he hasn’t done anything with COTS yet. On the prior logs from prior revisions I was seeing AFRs in the 13s in that low boost, low rpm, high load scenario before ever hitting 40% TPS so he definitely did something with it that was a step in the right direction.

 

He might be using the cylinder multipliers too. I've never tried screwing with those besides turning them off, but keep the thought as a last resort type of thing if the tune isn't working well. Since with that you can adjust individual cylinder fueling during a specific load/rpm range and it's independent of PE. Maybe/probably other ways to.