Details about my car mods first:
2016 6MT Golf R, APR Stage 2 high torque, CTS high flow catted DP, APR intake, APR coils, RS7 plugs, Southbend Stage 2 daily clutch, stock intercooler.
61k miles, no carbon cleaning yet, plugs were at 12k miles.
The electrode from spark plug in Cyl 3 broke off. Car threw P0303 and P0304 (cyl 3 and 4 misfire) and P0300 (random/multiple cylinder misfire).
Compression, leak down test and cylinder boroscope visual check passed. No metal in the oil on the dipstick. Replaced the old RS7 spark plugs with new stock plugs, went back to the stock coils. Car ran totally fine for about 30 miles, babying it. Then I gave it a 1-2-3 pull with about 3/4 throttle and let off. Instead of hearing pops and bangs when I let off like I normally would, I heard a new ticking sound. Limping it home 1/4 mile, the sound came and went intermittently. Car threw P0301 and P0302 (cyl 3 and 4 misfire) and P0300 (random/multiple cylinder misfire). Pulled the new plugs, they all looked fine.
I disassembled the downpipe and did not find the electrode. Turbine blades looked perfect, no shaft play in the turbo. Started it with the catback removed in hopes of blowing any metal bits out. No luck. Perhaps the electrode was so small by the time it broke off that it disintegrated?
The noise:
After the noise happened with the new plugs and that one pull I did with them, every time I restart the car, the noise does not come back at idle. I think it needs to be higher in the RPMs to recreate the sound. Car ran totally normal with no bad sounds at idle. Ran it for about 15 minutes and brought it up to 2k without issue. Was too afraid to take it out of the garage to run it down the street as I ran out of free tows. I took off the PCV valve off to see if it was a loose/damaged rocker arm, could only see a couple of them, all looked fine.
My next steps:
1. Use boroscope in the PCV opening to inspect the remainder of the rockers arms / valve train components.
2. Change oil and look for metal bits
3. Reassemble, see if problem comes back and if it does, use stethoscope to pinpoint sound. It sounds like it is definitely top end, not bottom end sound.
What do you recommend?
2016 6MT Golf R, APR Stage 2 high torque, CTS high flow catted DP, APR intake, APR coils, RS7 plugs, Southbend Stage 2 daily clutch, stock intercooler.
61k miles, no carbon cleaning yet, plugs were at 12k miles.
The electrode from spark plug in Cyl 3 broke off. Car threw P0303 and P0304 (cyl 3 and 4 misfire) and P0300 (random/multiple cylinder misfire).
Compression, leak down test and cylinder boroscope visual check passed. No metal in the oil on the dipstick. Replaced the old RS7 spark plugs with new stock plugs, went back to the stock coils. Car ran totally fine for about 30 miles, babying it. Then I gave it a 1-2-3 pull with about 3/4 throttle and let off. Instead of hearing pops and bangs when I let off like I normally would, I heard a new ticking sound. Limping it home 1/4 mile, the sound came and went intermittently. Car threw P0301 and P0302 (cyl 3 and 4 misfire) and P0300 (random/multiple cylinder misfire). Pulled the new plugs, they all looked fine.
I disassembled the downpipe and did not find the electrode. Turbine blades looked perfect, no shaft play in the turbo. Started it with the catback removed in hopes of blowing any metal bits out. No luck. Perhaps the electrode was so small by the time it broke off that it disintegrated?
The noise:
After the noise happened with the new plugs and that one pull I did with them, every time I restart the car, the noise does not come back at idle. I think it needs to be higher in the RPMs to recreate the sound. Car ran totally normal with no bad sounds at idle. Ran it for about 15 minutes and brought it up to 2k without issue. Was too afraid to take it out of the garage to run it down the street as I ran out of free tows. I took off the PCV valve off to see if it was a loose/damaged rocker arm, could only see a couple of them, all looked fine.
My next steps:
1. Use boroscope in the PCV opening to inspect the remainder of the rockers arms / valve train components.
2. Change oil and look for metal bits
3. Reassemble, see if problem comes back and if it does, use stethoscope to pinpoint sound. It sounds like it is definitely top end, not bottom end sound.
What do you recommend?