Okay guys, help me understand… I removed the stock airbox from my car, and at the same time the P/S and A/C and all associated plumbing and brackets. I installed a cone filter on the front of my AFM, making an adapter to upsize the mount of the AFM to 3.000” (stock is 2.555”). I take her out for a spin, and the car was detonating (took me a while and another post to figure out that the VERY strange noise was indeed detonation, never heard anything like it before). I checked the timing and it was about 10 degrees advanced. I had never checked it before, but I had never heard the car detonate before either. Could it be that the new filter allows so much flow that the Air/Fuel ratio is now incorrect? Should I richen it up? How can I do this with the stock ECU?? I had to go to about 1-2 degrees retarded to get the detonation to completely stop. Is there anything that I could have disconnected that would have advanced the timing?? Thanks for all of your help!

 

I don't think you had detonation man. Check your plug wires to see if they are crossed. you can not adjust the a/f mix without a fuel computer or EMS. A cone filter would not make you have detonation. something else must be doing this.

 

Well, I did mention that the timing was 10 degrees advanced. I just don't believe it was before. As for the wires, I am sure they are correct, and they were not removed!!

 

Did you add a cold air box with the cone filter. Just bolting in a cone filter with all that hot air from around the engine and your timing advanced that far; pretty much would cause knocking/detonation right there.

 

Bump

 

Well, my road tests were done in 45 degree weather, and it does it before the car is warm, and no I don't have a cold air box, that's next.

 

Tell you what then, since you don't believe me, put the stock air box back in and see if you have the same problem.

If the problem goes away, you'll know it is exactly what I said.

 

set the timing to normal, and do some carbon removal. Pull off the vacuum line by the oil injectors I think, and put it into a bucket of water while the engine is held at 3000 or so. Go with a gallon or two. This will remove the carbon, lower your compression ratio, and hopefully stop the detonation.