Spark knock after Installing a K@N Cold Air Intake

[ballard2327]

Hi everyone,I have a problem that mabe one of you may have an answer to or mabe some idea of what I might do to correct this.I'm running 93 octane,no codes,and am getting the spark knock on slow accelaration.When I kick into passing it goes away.I have a 2004 Pontiac Grand Prix GT2(3800 series3 non-supercharged)I did a very nice tune-up with coils,Bosch plugs,10.3 Mil wires.But it did'nt help at all.Any advice would be appriciated.After reading the other threads,I'm confused about the whole spark plug issue.I just placed Bosch Platinum/IR plugs in my car.Now I'm reading that a colder plug by AC Delco would be better.I'm afraid I'm not very up on the new tech on the new cars.If my car was supercharged it would be easer to find info,but being just a 3800 non-supercharged it is very hard to find answers to my problem.Please if anyone can point me in the right direction,please tell me about what plugs,MAF,ect.Sincerely

[CrazyHorst]

Here's a quick primer on the hot/cold plug issue.

This has to do with how well the plug conducts heat. In other words a "hotter" plug electrodes will stay at a higher temperature than a colder plug. The basic tradeoff is that a hotter plug will stay cleaner and burn off fouling, whereas it can also become a lightning rod for premature ignition, which likely shows up as knock.

In other words...suppose there's this little glowing metal point in the combustion chamber as the air/fuel mixture is compressed. If the right circumstances prevail, the glowing metal can start combustion before the electrical energy jumps the gap via normal ignition.

A "colder" plug will allow more heat to be conducted back into the cylinder head (and eventually water jacket) and so the electrode stays below the critical temperature.

I'm not up to speed on which plugs give good field results on the NA 3800 (L36). I used Delco 41-101s on the L67 with apparently good results so far.

[grandprixgtx00]

take the Bosch plugs out and put AC Delco or NGK in...guaranteed your knock will go away.

we all know what we here on the forum think about Bosch plugs...

[BNaylor]

Originally Posted by ballard2327

I'm running 93 octane

On the 2004 and up Grand Prix the 3800 engine is a Series III 3800 engine. L26 for NA and L32 for supercharged.

Why is the OP running 93 octane gas? The L26 like its L36 counterpart/predecessor is made to run on regular unleaded 86-87 octane.

[tblake]

How can you be sure that you have "spark knock"? Are you measuring it with a scan guage?