Spark knock ? ):

[j221282]

03 marauder 300a is now spark knocking under light/ moderate acceleration, she has 109k miles I pump 93 from chevron and Exxon, I have changed out the spark plugs didn't solve the problem, cleaned maf, changed out air cleaner , replaced egr valve, still pinging , tried seafoaming it no results, how do I know it's spark knock? Mhm it only pings when full operating temp , no engine light is on, took the car to a mechanic hooked on the computer and said everything checks out good, stock tune stock thermostat .. What's my next step??

[RF Overlord]

Could be carbon'd up. Do you drive with a light foot? If so, do an Italian Tune-up.

[fastblackmerc]

03 marauder 300a is now spark knocking under light/ moderate acceleration, she has 109k miles I pump 93 from chevron and Exxon, I have changed out the spark plugs didn't solve the problem, cleaned maf, changed out air cleaner , replaced egr valve, still pinging , tried seafoaming it no results, how do I know it's spark knock? Mhm it only pings when full operating temp , no engine light is on, took the car to a mechanic hooked on the computer and said everything checks out good, stock tune stock thermostat .. What's my next step??

If it really is spark knock then your motor will be self destructing shortly.....

If it only happens at operating temperatures check for loose or cracks in your exhaust manifolds.

[JoeBoomz]

If you restore to stock tune does the problem go away?

[RR|Suki]

If it really is spark knock then your motor will be self destructing shortly.....

If it only happens at operating temperatures check for loose or cracks in your exhaust manifolds.

This^ a long time ago I had a tick caused by my stock manifolds not being tightened properly.

[babbage]

03 marauder 300a is now spark knocking under light/ moderate acceleration, she has 109k miles I pump 93 from chevron and Exxon, I have changed out the spark plugs didn't solve the problem, cleaned maf, changed out air cleaner , replaced egr valve, still pinging , tried seafoaming it no results, how do I know it's spark knock? Mhm it only pings when full operating temp , no engine light is on, took the car to a mechanic hooked on the computer and said everything checks out good, stock tune stock thermostat .. What's my next step??

New Thermostat, new water pump, flush cooling system. Bet that cures it.

[ctrlraven]

How long has it been going on and was anything done or changed (replace a part, fuel up at a different station that normal) before it started?

[1stMerc]

How soon did this start after your last fill up? Maybe bad gas.

[boatmangc]

Or maybe a dirty fuel filter causing a lean condition

[j221282]

How long has it been going on and was anything done or changed (replace a part, fuel up at a different station that normal) before it started? i once let my sister drive my car and she pumped 87 but even then it wasnt pinging, started about 5k miles ago, increasingly getting louder, ive since stop driving the car on long hauls

[j221282]

Or maybe a dirty fuel filter causing a lean condition
i changed that out too sorry i did not mention that

[j221282]

Got advice by zach and burped the system, had decent amount of air in the system , pinging is so light you have to really pay attention and stick your head down under the glove box to be able to hear it,

[Zack]

Are you positive you don't have an exhaust leak?

[j221282]

Are you positive you don't have an exhaust leak?

The burping did help a lot in fact it almost fixed it but it's still pinging very lightly, and honestly I don't know , if there is an exhaust leak I would be able to smell the fumes from the engine bay correct ? I don't

[fastblackmerc]

The burping did help a lot in fact it almost fixed it but it's still pinging very lightly, and honestly I don't know , if there is an exhaust leak I would be able to smell the fumes from the engine bay correct ? I don't

Not necessarily.

[j221282]

Update , deleted rear cats , and tried some Lucas octane booster, sparck knock is gone for now, I pump 93 at Exxon or chevron, octane boost really worked but I still think theres something wrong I would hate to have to buy a 10$ octane booster every time I fill up anyone have any suggestions ?