Hey, when I accelerate I hear a funny sound from the car, like some little pops.
Now I have my S-AFC set from -9% to -14% in the Low Throttle position. When I brought everything back to 0% the sound dissappeared.
Could that be detonation? I've got an n/a so I dunno!

Thanks!

 

wow that's pretty low!!... do you ahve bigger primary injectors?

it very well could have be detonation. it's usaly a lot of "pinging" noises in a row. kinda like popcorn.

 

Huh oh, I think that was that!
Goddamn A/F gauge, it was showing rich!
Oh well, now I'm just gonna save money and go on a dyno.
thanks!

 

very wierd, just wonder but do you have a new S-AFC?

 

yeah I got the 2nd gen one. I'm still running stock injectors too.
Let's hope I didn't mess up anything!

 

does it happen on the throtle or off?

 

There are two kinds of detonation, mild and severe.

Severe detonation is loud, and very noticable. It sounds like a loud "*****!".

Mild detonation is a little more difficult to detect. It is often described as what sounds like popcorn popping.

You're S-AFC settings are way too low, and you are probably detonating the engine. Best increase your fuel before you damage something. BTW, A/F guages are NOT a reliable way to tune the car. I have shown full rich on my guage, yet have been clearly detonating the engine...

 

It happened when I press the throttle at about 30%. At WOT I had the setting a little lower so thank God I didn't blow my engine!

 

So is afterburn mild detonation then? I thought it was unspent fuel hitting hot exhaust pipes. It definitely sounds like popcorn though...

Steve

 

So is afterburn mild detonation then? I thought it was unspent fuel hitting hot exhaust pipes. It definitely sounds like popcorn though...

Steve

 

Yes, it sounds the same.


-Ted

 

Start your lawnmower up and spray starter fluid in its intake at high throttle. That is pinging, knock whatever. With just a little luck you will destroy the engine and not have to cut the lawn the rest of the year.