Hey guys, I’ve been having an intermittent issue with my 2016 when I go full throttle (usually in first or second gear) where it feels like the throttle snaps closed and I loose all power around 4500 RPMs for a couple of seconds and then I comes back after I shift and doesn’t set any DCTs or CEL. I’ve searched through the forums for anyone experiencing the same problem but I haven’t been able to find anything that is close enough for me to to think it’s the same thing. I have a couple of mods (intercooler, intake, muffler and resonator delete) and most recently a Cobb access port with the OTS stage 2 93 octane tune but I have been experiencing the issue even on the stock tune although it might be a tad bit more frequent with the tune.
I posted something about this on the fiestaST subreddit and under advice of a comment checked for boost leaks and found one coming from the diverter/blowoff valve spacer that the previous owner installed so I removed it and that seems to have fixed the leak but still the issue persists. At this point I’m thinking that it’s either LSPI or something to do with the traction control system since I spin tires a bit in first and second gear at full throttle but I’m leaning towards LSPI for 3 reasons. I never spun tires in second on the stock tune and I’ve experienced the issue with traction control disabled, I’ve noticed my knock detection parameter on my access port go up 1 when I’ve experienced the issue, and finally I just installed step colder plugs gapped at .025”yesterday and I felt like the issue got worse when I took it on a test drive last night.
All of this to say I’m pretty unfamiliar with how the ECU handles knock detection on these cars but is it common for the throttle to snap closed when knock/LSPI is detected? I have also never really experienced what it’s like to have timing pulled aggressively so maybe that’s what’s happening but I don’t realize it. My next course of action is probably going to be changing my oil to royal purple full synthetic 5W-30 since I think I used a synthetic blend last time I changed the oil. Any tips or suggestions would be appreciated, Thanks!
I posted something about this on the fiestaST subreddit and under advice of a comment checked for boost leaks and found one coming from the diverter/blowoff valve spacer that the previous owner installed so I removed it and that seems to have fixed the leak but still the issue persists. At this point I’m thinking that it’s either LSPI or something to do with the traction control system since I spin tires a bit in first and second gear at full throttle but I’m leaning towards LSPI for 3 reasons. I never spun tires in second on the stock tune and I’ve experienced the issue with traction control disabled, I’ve noticed my knock detection parameter on my access port go up 1 when I’ve experienced the issue, and finally I just installed step colder plugs gapped at .025”yesterday and I felt like the issue got worse when I took it on a test drive last night.
All of this to say I’m pretty unfamiliar with how the ECU handles knock detection on these cars but is it common for the throttle to snap closed when knock/LSPI is detected? I have also never really experienced what it’s like to have timing pulled aggressively so maybe that’s what’s happening but I don’t realize it. My next course of action is probably going to be changing my oil to royal purple full synthetic 5W-30 since I think I used a synthetic blend last time I changed the oil. Any tips or suggestions would be appreciated, Thanks!
