Loving my LTG ATS but Fighting Tip In Knock. Flex Fuel Tune Attached.
2014 ATS with LTG 2.0 AWD Turbo. Loving the car, had about 6 months and just starting to play with it. Getting knock at tip in. Please help/advise if you can.
Mods are
Injen cold air intake.
Car has one heat range cooler plugs. NGK?s.
E85 sensor and flex fuel tune.
Otherwise stock.
Attached log is a drive after adding E85 onto 1/2 tank of 93 octane.
You can watch the E85 sensor (ethanol fuel % channel, alcohol percent channel) increase as I drive
By the way, does anyone know why these ethanol/alcohol channels lag each other? Given enough time, they will match.
I get knock at tip-in. I can hear it sometimes.
Happens on 93 more often than E85, but I do hear it on occasionally even on E85.
Car seems to be down on boost as well. I see 28-29 psi. Been told that these cars run 32 when everything is happy.
Car has 80,000 miles. Seems like it was well maintained. Recent oil change with Mobil 1. I am starting to wonder if it has a bunch of carbon buildup on intake valves. I ran some of the seafoam GDI (gasoline direct injection) cleaner through the intake, not sure if it helped. Certainly didn't hurt anything. Currently running a can of seafoam through the gas tank.
Before I pull the head off and deep clean this thing, I want to chase down any other known issues.
Log and tune attached. First example of what I am trying to fix is at time 2:13. Second example at 5:10. There is very little timing in it, and I just don't understand why it knocks so easily.
Regarding the knocking, that's just what these engines do. You'll get a good calibration running, and you'll find it still knocks audibly, seemingly randomly. It even happens on the stock calibration. It might be related to the reason that they are known for breaking pistons also.
Those boost levels are way too high unless you're considering the absolute MAP to be "boost". In which case "29psi" is ~200kPa absolute pressure, which is, at sea level (atmosphere 100kPa, so 200 - 100 = 100 * .145 = 14.5), actually about 14.5psi of boost, and, yes that is low for these engines. You need to figure out if its the calibration or hardware that's limiting you.
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