2020 JLU Spark Knock

[BuffDad]

Folks, I have a 2020 with manual trans and the 3.6 Pentastar, with 30K miles. I have a spark knock that requires 93 octane; the mid-grade 89 octane still produces occasional spark knock. I’m thinking the oil catch can mod might be beneficial as oil in the intake produces carbon which can cause spark knock.

Would appreciate all of your thoughts and suggestions. I am aware of the TSB but the cost would be prohibitive.

Sponsored

 

[speedymart]

Normally running 89 solves any knocking with the upgraded 3.6.

That being said, the TSB is just a cleaning procedure with an excessive amount of detail to it. The fix is to replace the PCV valve with an updated part 68609110AA ---

Suggest replacement of the PCV valve and do your standard fuel injection service which involves running a cleaner through the intake. Once you do that go drive the piss out of it. The idea is to get it as hot as physically possible to burn off any carbon that may still be left. The problem will become less and less after it is driven.

The TSB has you remove both cylinder heads to physically clean the piston surfaces which is honestly ridiculous. Though it would be covered under your powertrain warranty, which it appears you probably are. Have your dealer run this LOP: 09353093 to see if it's covered.

I'd be skeptical of a dealer technician actually carrying out this procedure instead of just running cleaner through it and driving the piss out of it after replacing the PCV. 11 hour isn't very much considering the work involved in removing both heads on a JL. Cash pay is like 18.

 

[BuffDad]

Normally running 89 solves any knocking with the upgraded 3.6.

That being said, the TSB is just a cleaning procedure with an excessive amount of detail to it. The fix is to replace the PCV valve with an updated part 68609110AA ---

Suggest replacement of the PCV valve and do your standard fuel injection service which involves running a cleaner through the intake. Once you do that go drive the piss out of it. The idea is to get it as hot as physically possible to burn off any carbon that may still be left. The problem will become less and less after it is driven.

The TSB has you remove both cylinder heads to physically clean the piston surfaces which is honestly ridiculous. Though it would be covered under your powertrain warranty, which it appears you probably are. Have your dealer run this LOP: 09353093 to see if it's covered.

I'd be skeptical of a dealer technician actually carrying out this procedure instead of just running cleaner through it and driving the piss out of it after replacing the PCV. 11 hour isn't very much considering the work involved in removing both heads on a JL. Cash pay is like 18.

Good thoughts! Thank you! What do you think about me running SEAFOAM through the throttle body?

 

[speedymart]

Good thoughts! Thank you! What do you think about me running SEAFOAM through the throttle body?

Seaform is technically the same thing. At the shop we use the MOPAR air intake cleaner p/n 68597177AA and run it through a tool that's hooked up to shop air to spray it directly into the throttle body while we have the engine running at ~2000 RPM. Then we go drive the piss out of it and you'll see a MASSIVE smoke cloud and get some misfires as it works its way out.

 

[BuffDad]

Seaform is technically the same thing. At the shop we use the MOPAR air intake cleaner p/n 68597177AA and run it through a tool that's hooked up to shop air to spray it directly into the throttle body while we have the engine running at ~2000 RPM. Then we go drive the piss out of it and you'll see a MASSIVE smoke cloud and get some misfires as it works its way out.

Thank you!

 

[BuffDad]

Thank you!

BTW, MOPAR is calling for P/N 68210345AC for the PCV. Does P/N 68609110AA replace 68210345AC?

 

[BuffDad]

BTW, MOPAR is calling for P/N 68210345AC for the PCV. Does P/N 68609110AA replace 68210345AC?

Looks like 68210345AC replaced 68609110AA. https://www.jlwranglerforums.com/forum/threads/new-version-of-pcv.113454/

Sponsored