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ike84 · 07-30-2021, 05:14 PM

The dme analyzes feedback from the knock sensors to detect preignition and detonation. Low octane gas in high compression motors can cause both, although detonation (aka knock) is fast more likely. These events do not throw a code per se, but instead causes the dme to retard timing in an attempt to minimize this from occurring.

Misfires, on the other hand, are caused by lack of detonation in a cylinder and are picked up by variations speed calculated from input from the crankshaft position sensor relative to what cylinder is (or should be) during at that moment.

In other words, bad gas usually doesn't cause a misfire. It just makes the engine run like **************** until the dme pulls timing to compensate and then you lose power.

I would pump out the gas, put in fresh 93, and hope for the best. If it continues to happen, double check your work. And call a priest, because yo **************** is haunted.

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07-30-2021, 05:14 PM	#162
ike84 Registered User Join Date: Oct 2020 Location: KY Posts: 1,214	The dme analyzes feedback from the knock sensors to detect preignition and detonation. Low octane gas in high compression motors can cause both, although detonation (aka knock) is fast more likely. These events do not throw a code per se, but instead causes the dme to retard timing in an attempt to minimize this from occurring. Misfires, on the other hand, are caused by lack of detonation in a cylinder and are picked up by variations speed calculated from input from the crankshaft position sensor relative to what cylinder is (or should be) during at that moment. In other words, bad gas usually doesn't cause a misfire. It just makes the engine run like ************** until the dme pulls timing to compensate and then you lose power. I would pump out the gas, put in fresh 93, and hope for the best. If it continues to happen, double check your work. And call a priest, because yo ************** is haunted. Sent from my SM-G970U1 using Tapatalk __________________ 2000 Box Base, Renegade Stage 1 performance mods complete, more to come When the owners manual says that the laws of physics can't be broken by this car, I took it as a challenge...