KR, Negative LTFT, Low Boost

Nice that'll do it to glad the code is fixed

 

Just wanted to update the page. The problem is still unresolved. I thought that my extreme post intercooler temps were to blame for my knocking. So I installed a 250cc methonal jet with a fully “custom” kit that I pieced together. It definitely helped with the temps. In this weather a 0 to 100 pull would send my temps skyrocketing over 160 degrees in full boost. Now it’s around 100. I have noticed that the knock isn’t as bad (according to AP) now that the meth kit is on. I’m still seeing 5.95 KR above 5k. Next on the list is boost leak test, ethanol content testing on my “no ethanol 91” and a custom tune. At this point I’m just posting my findings in case anyone else in the near future is having this issue.

 

Something very odd happened tonight. I found the launch control feature on my AP so I had to try it out. I also adjusted the wastegate duty multiplier just to see what happened. I boosted it around launch after launch just having some fun. Then it wouldn’t rev past 5k rpms. Sounded the exact same as the launch control limiter. Launch control worked at 3500rpm but it wouldn’t rev past 5k in any gear or speed including neutral. I stopped and reflashed the stage 1 +sf map with 0% duty multiplier and the same launch control settings. It HUALED ASSS after that. What I noticed was my check engine light wasn’t on. I check my codes often. I always get the same codes (egr, shutter valves, and one tire pressure code). This time they never came on. The car pulling and I mean pulling all the way to redline with .30 KR. my question is. What have I done for this to “fix itself”. I don’t have any hope that it will be like this in the morning as this car has shot down my ideas one after another. I’m just hopeful that with each clue it will lead me to the big issue.

 

Sounds like A bad flash was corrected with an ecu re-flash.

For the record you're crazy trying launch control and wot while having issues like this good way to blow things up.

 

Yea I do know better. I’ve just gotten really used to not going above 5k (which is where I get knock). So is there a possibility of the actual tunes being bad rather than a mechanical issue. I’m going to drive it again sometime to see if it’s still not knocking.

 

I’ve got another lead on the issue. Now to explain the situation. I just bought a very nice MS6. I pulled into a hutches and put some 91 in it when I first bought it. It ran fine all the way home no knocks. I live in the middle of no-where. (There is actually a town called “no-where” very close to me). So I only have one “91” pump to use in a neighboring town. I asked the store owner when I first bought my ms3 if he had ethonal in his fuel. He went into a big spill about his truck not running right on ethonal so he made sure he had a 91 no elthonal pump. After filling up at the local watering hole the MS6 starting knocking at cruising rpm and boosted pulls. Currently weighing my options of having a little talk to the store owner about my low compression engine and his Mis-advertised fuel. I’ll be getting a ethonal tester just to see how much he’s lying to me. I only have 87 ,89 no ethonal, 91 ethonal and “91 mystery sauce but advertised as no alcohol” to choose from in a 60 mile radius. Hauling fuel in drums or driving an hour for fuel is my first two options. I’m curious if there’s any remedy’s. I know of paint thinner but it’s extremely expensive. Octane booster doesn’t work. I’ll be going to another town after siphoning this fuel out to test my theory. The only other thing I can think of is hauling fuel in some of my 55gallon drums. I just don’t like storing fuel and having to pump it out of a metal barrel. Evaporation is a killer with that too. Any suggestions. At this point I’m venting. I apologize.

 

Maybe it was just a one-off where he got a bad batch of gas? Or maybe try the regular, ethanol containing 91 next time instead of the mystery 91? Shitty situation no matter what though. I know I'd be skeptical about filling up there in the future if it happened to me but your other options don't sound great either.

 

I tested my findings by going to another gas station an hour away. I bought 90 dollars worth of 91 “ethanol free”. These pumps clearly said no ethanol but I’m still skeptical. I sucked my tank dry and filled with the new gas. Same knocking. The only thing I realized is that both gas station are supplied with fuel from TOP TIER fuels. I emailed top tier with my story and situation. I don’t expect to hear anything back. The only other fuel I can abtain and store is airplane fuel. It’s around 4 or 5 dollars a gallon and it’s around 100 or 105 octane. I can’t remember what my friend said. He’s a local pilot and hauls fuel for his airplane. I know you don’t have to change jetting or anything because the local fire dept runs all their equipment motors on it as it doesn’t EVER go bad. I plan to come back and live my life here after college so I need to find a permanent solution. Is their any gas commission that I could call? I appreciate any input on what I should do.

 

I drove to Lawton (the closest largest city). I went to Walmart, sams, 3 different comer stations and love’s on the interstate back home. EVERYTHING has ethanol in it. Lawton is basically a military base and with that comes all the turbo sports cars that military men and women drive. I wonder what they get. I found 110 race gas but it’s over 8 dollars a gallon at the pump. I’m going to try airplane fuel first on the ms3 and see what happens. At this point I’m looking at getting the Cobb tuning software because I could tune for the 10% 91 or what ever it is. This situation is screwed up in every way.

 

Are you still on an OTS tune and not a better dialed in tune? Throwing higher octane in isn't going to solve your issue.

 

I just purchased and went through the entire Cobb tuning course. I learned that the ecu logic doesn’t learn octane. it’s a strictly “reactive” based knock control system. I also learned that going into high det mode is extremely rare for these cars. I will be setting more parameters and more excessive adjustments when knock is heard to protect my engine. I’ll be turning up the “knock enrich” as well as tuning a tad richer in case of ethanol.

 

Just to update the thread. Problem is still unresolved. I drove my MS6 to college and got very proficient at tuning on these cars. MS6 is an absolute blast. I decided to bring the ms3 up here and start tuning. I ported over my e10 16psi tune from my MS6 to the ms3 and it’s still knocking. I’ve noticed on wot to no throttle that It hits 8 KR on one cell. So for Christmas I’m getting motor mounts and a full suspension kit. The suspension is really loose and popping, maybe it’s causing noise in the motor. I’m gonna switch the knock sensor over from my MS6 and see if it’s a knock sensor. The car really doesn’t feel like it’s actually knocking. It’s retarding up to -5.5 total ignition timing at 5500-5600 and it feels like 2 step. I’m selling a few cars so a basic engine rebuild might be in the works.