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Hey guys, I had long tube headers installed on my 2015 C7 several weeks ago and the car was running great. I had it tuned and all. I took it out the other day and was really gunning the throttle and flooring it to feel the power. Towards the end it started lagging and stuttering a little. An engine light came on but then went off. I checked the code and is was Random Misfire Code P0300 . Any idea why this could be happening?
I hope so man! Im gonna get in there tomorrow and check things out.
Almost sounds like a knock sensor. The knock sensor detects the slightest knock and will send data to the ECM which will begin causing the car to become sluggish (on purpose). The sensor is probably ok and doing its intended job but you mentioned putting headers on the car. There may be an issue with the headers causing a knock. A possibility anyway!
I just had a flashback to days when there were no “codes”.. timing was set by turning the distributor clockwise or counter, plugs were all visable and accessible and headers usually meant just adjusting the jets in the carb.... now its rocket science.
aybe something similar to the random high rpm wide open throttle misfires I was getting on track. Check the coolant level in the intercooler reservoir. There may be too much air in the intercooler system causing high temp air to enter the cylinders. You don't want any more air in the intercooler than what is shown in this picture:
Bill
Last edited by Bill Dearborn; 11-14-2018 at 05:24 PM.
Looks like that's what it was! Maybe got knocked a little loose when they did the header install? The boot was pretty much off of the spark plug. Thanks for the suggestion!
aybe something similar to the random high rpm wide open throttle misfires I was getting on track. Check the coolant level in the intercooler reservoir. There may be too much air in the intercooler system causing high temp air to enter the cylinders. You don't want any more air in the intercooler than what is shown in this picture:
Bill
Ill check that out too just to be on the safe side. Thanks!
Looks like that's what it was! Maybe got knocked a little loose when they did the header install? The boot was pretty much off of the spark plug. Thanks for the suggestion!
Cool. I had just gotten my ZR1 back from the shop and it was doing something similar. Loose plug wire was the problem so I thought I would pass it along. Usually they recommend removing the plugs and wires so you don't crack them installing headers so I thought it might be the case.
Cool. I had just gotten my ZR1 back from the shop and it was doing something similar. Loose plug wire was the problem so I thought I would pass it along. Usually they recommend removing the plugs and wires so you don't crack them installing headers so I thought it might be the case.
Whoa... didn't realize you owned the ZR1. Congrats on that! Do you have any footage of that monster?
11-13-2018, 06:15 PM
Random Misfire Code P0300
