So I've getting some pretty bad negative corrections at WOT lately. This is on a Dizzy Stage 2 tune for 93 on the stock turbo, but I've experienced the same when I switched to the Cobb Stage 3 OTS tune. OAR has no problem getting to -1.0 under mid throttle and normal driving, but as soon as load gets high in anything higher than 2nd gear, I get a ton of negative corrections and OAR plummets back to anywhere from -0.5 to -0.2. Even part throttle on higher gears can get some pretty nasty negative corrections at times. Jason has been helping where possible, but I know he's busy and I'm hoping someone here has had a similar experience and found a fix.
I'll start by saying I don't think it's bad gas. I have gone to at least 10+ gas stations so far and in 4 different states, a vast majority being stations with Top Tier gas, yet the behavior is the same. Other than that, I've tried: changing out my old plugs to new NGK Ruthenium plugs pre-gapped by Ron to 0.028 (more like 0.026-0.027 when I double-checked them today, but I'm not going to open them back up for a 0.001 inch difference), changed my factory coils with 60k miles on them for Whoosh coils, and walnut blasted my intake valves.
Here is an original data log: https://datazap.me/u/plisky/dizzy-stage-2-old-plugs?log=0&data=7-9-10-11-12
and here is another after the new plugs, coils, and cleaned intake valves: https://datazap.me/u/plisky/dizzy-s...s-and-cleaned-valves?log=0&data=7-10-11-12-13
The only thing that has had any effect so far was yesterday when I added a gallon of E85 to my 8 gallons of 93 then drove around for 15 or so miles before going WOT in 3rd from 2500-6500 rpm (sadly I didn't log this since my log monitors were empty). At first I still got negative corrections, but they were far less this time, with -2.25 max rather than the usual -6~, and this was also the first time I've ever gotten any positive corrections at WOT, as past 3500 it actually started adding positive corrections. OAR still dropped from -1.0 to -0.93 when the pull was done, though, and knock count for cyl 1 hit 7, which sounds bad. I know some may say that this points to bad gas, but if I have gotten bad gas at every individual gas station so far, then I don't think good gas actually exists.
Things I've not tried yet which have been recommended to me include checking the motor mounts to see if they might be introducing false knock, checking the knock sensors themselves, and checking the timing belt.
Before applying the tune I had the timing belt replaced at a shop and it was a total shitshow; they couldn't get the car started for a week afterwards and I'm guessing it's because they were struggling with the timing, and after I got it back I found some sloppy work, like one of the driveshaft bracket bolts being almost completely out. After telling Jason about this, he thinks that the belt could have jumped a tooth and said he would send me some instructions to check it myself soon. In the mean time, if anyone else knows what I can do aside from opening the timing cover up, I'd be happy to know.
My modifications are a Whoosh Motorsports V3 intercooler, NGK Ruthenium HX plugs gapped to .028, ST200 air intake with Velossa Tech Big Mouth Ram, Whoosh street-spec RMM, and a symposer delete.
I'll start by saying I don't think it's bad gas. I have gone to at least 10+ gas stations so far and in 4 different states, a vast majority being stations with Top Tier gas, yet the behavior is the same. Other than that, I've tried: changing out my old plugs to new NGK Ruthenium plugs pre-gapped by Ron to 0.028 (more like 0.026-0.027 when I double-checked them today, but I'm not going to open them back up for a 0.001 inch difference), changed my factory coils with 60k miles on them for Whoosh coils, and walnut blasted my intake valves.
Here is an original data log: https://datazap.me/u/plisky/dizzy-stage-2-old-plugs?log=0&data=7-9-10-11-12
and here is another after the new plugs, coils, and cleaned intake valves: https://datazap.me/u/plisky/dizzy-s...s-and-cleaned-valves?log=0&data=7-10-11-12-13
The only thing that has had any effect so far was yesterday when I added a gallon of E85 to my 8 gallons of 93 then drove around for 15 or so miles before going WOT in 3rd from 2500-6500 rpm (sadly I didn't log this since my log monitors were empty). At first I still got negative corrections, but they were far less this time, with -2.25 max rather than the usual -6~, and this was also the first time I've ever gotten any positive corrections at WOT, as past 3500 it actually started adding positive corrections. OAR still dropped from -1.0 to -0.93 when the pull was done, though, and knock count for cyl 1 hit 7, which sounds bad. I know some may say that this points to bad gas, but if I have gotten bad gas at every individual gas station so far, then I don't think good gas actually exists.
Things I've not tried yet which have been recommended to me include checking the motor mounts to see if they might be introducing false knock, checking the knock sensors themselves, and checking the timing belt.
Before applying the tune I had the timing belt replaced at a shop and it was a total shitshow; they couldn't get the car started for a week afterwards and I'm guessing it's because they were struggling with the timing, and after I got it back I found some sloppy work, like one of the driveshaft bracket bolts being almost completely out. After telling Jason about this, he thinks that the belt could have jumped a tooth and said he would send me some instructions to check it myself soon. In the mean time, if anyone else knows what I can do aside from opening the timing cover up, I'd be happy to know.
My modifications are a Whoosh Motorsports V3 intercooler, NGK Ruthenium HX plugs gapped to .028, ST200 air intake with Velossa Tech Big Mouth Ram, Whoosh street-spec RMM, and a symposer delete.
