Greetings all,
I have a 2016 Golf R with around 13,000 miles. I bought it earlier this year and haven't driven it a ton but when I did, everything was perfect. It was bone stock.
I recently installed a cat-back exhaust on it and it was driving fine after that as well. Then, my battery died.
I'm not sure if the battery dying has anything to do with everything that came after, but it was the start of a bad string of luck. I replaced the battery and started it, got a million alerts on the dash screen (from trying to start it with the dead battery), things like traction control and tire pressure, all of which were fine. Those went away and I took it for a drive.
When I hit high RPMs the car begins to chug, the EPC light comes on, and it goes into limp mode until I shut it off. Once I shut it off, I can turn it back on again and it runs perfect UNTIL I hit higher RPMs again (around 5-6k).
The code I get is for a cylinder 4 misfire.
After all of this I noticed that the coil in cylinder 4 is a replacement coil, so this must have happened to whoever had the car before me (in the first 12k miles) and they replaced the coil.
I'm tempted to just replace the coil again, but replacing that coil twice in under 15k miles seems... not right, and I'm thinking something else is going on here. I've read a bunch of threads about P0304 and some of them mention rolling back their ECU tunes and whatnot, and I don't THINK this car has a tune, but I honestly don't know for certain (I bought it from Carvana).
What is the next step here? Roll the dice on a new coil? If something else is causing the EPC issue and then it goes into limp mode, and the car misfires in limp mode, the misfire code might be a red herring and I might be chasing the wrong problem. I don't know if the exhaust has anything to do with it, like if there's a massive leak (I don't hear one, but who knows) that is causing cat issues or something?
Thoughts?
I have a 2016 Golf R with around 13,000 miles. I bought it earlier this year and haven't driven it a ton but when I did, everything was perfect. It was bone stock.
I recently installed a cat-back exhaust on it and it was driving fine after that as well. Then, my battery died.
I'm not sure if the battery dying has anything to do with everything that came after, but it was the start of a bad string of luck. I replaced the battery and started it, got a million alerts on the dash screen (from trying to start it with the dead battery), things like traction control and tire pressure, all of which were fine. Those went away and I took it for a drive.
When I hit high RPMs the car begins to chug, the EPC light comes on, and it goes into limp mode until I shut it off. Once I shut it off, I can turn it back on again and it runs perfect UNTIL I hit higher RPMs again (around 5-6k).
The code I get is for a cylinder 4 misfire.
After all of this I noticed that the coil in cylinder 4 is a replacement coil, so this must have happened to whoever had the car before me (in the first 12k miles) and they replaced the coil.
I'm tempted to just replace the coil again, but replacing that coil twice in under 15k miles seems... not right, and I'm thinking something else is going on here. I've read a bunch of threads about P0304 and some of them mention rolling back their ECU tunes and whatnot, and I don't THINK this car has a tune, but I honestly don't know for certain (I bought it from Carvana).
What is the next step here? Roll the dice on a new coil? If something else is causing the EPC issue and then it goes into limp mode, and the car misfires in limp mode, the misfire code might be a red herring and I might be chasing the wrong problem. I don't know if the exhaust has anything to do with it, like if there's a massive leak (I don't hear one, but who knows) that is causing cat issues or something?
Thoughts?
