04 K1500 Spark Knock

04 4x4 Ext cab Short bed It's a 5.3 auto, 3.73 gears

Purchased Oct 18 with 24 miles. It now has 5600 miles on it. Spark Knocking like crazy.

I've ran several tanks of 87 octane through this with no improvements.

Problem: On part throttle, it has predetonation intermittently. When I say intermittently, I mean to what degree is intermittent. It always spark knocks.

On full throttle, it spark knocks like crazy over 3500 RPMs. Its bad enough that I can hear it over my exhaust (Flowmaster original 40 series through the stock piping).

Is this problem typical of this year? Any common fixes?

I am planning for a lift and looking for software to support upgrades in the future. If spark knock is something that's common for this engine and typically blown off or can't be fixed without seriously affecting performance, it will probably nix the planned performance upgrades.

I plan to take it in to have it evaluated, but I always like to know if my problems are typical or not.

Thanks,

Marc

Reply to
Marc
Loading thread data ...

Spark knock is not normal for ANY engine. Take it to the dealership for a warranty repair.

Doc

Reply to
"Doc"
87 octane? Where do you live? In my area thats the lowest octane, try to find some higher. Are you sure you are hearing spark knock (not to be a smartass) and not something else that may be loose or making the noise? Definately take it to the dealer, should be a warranty repair. tad
Reply to
ottertailfamily

why run something else if that is what the book calls for? I live in S GA.

Yes I can tell the difference between Spark knock and rattles. Thanks for the suggestions though.

Reply to
Marc

Marc's truck is MADE to run on 87, and would run shitty on anything lower (if it exists) or anything higher - I've even heard some makes say it will void your warranty. The last year of TBI would have been the last year you could run higher octane to try to fix spark knock (I run '89 religiously)

GMC Gremlin

Reply to
GMC Gremlin

MotorsForum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.