kongdong

I have an 03 GT supercharged and as of lately I've noticed that when I press the gas pedal I hear a chattering sound come directly from the center of my engine. It doesn't sound like a knocking sound and I use 93 octane fuel. Does anyone know what it could be?

cliffyk

It is pinging, aka detonation, and it's bad...

It could be that the warmer weather has raised the IAT--the resolution will likely be to back off the spark advance. I have three seasonal tunes (we only have 3 seasons here--OK, Hot, and damned HOT) each of which has different levels of spark advance.

Whatever the cause when you hear it back off the gas immediately, and then until you get it resolved, try to avoid pushing the engine to where it pings.

kongdong

Come to think of it sometimes in the mornings I don't really hear it all that much. However I hear it when I'm not beating on my engine. What can I do to find out? The tune I got was only to give me 353/383rwhp and I know my motor can handle that. What gives?

cliffyk

Without hearing it myself I cannot really offer any concrete advice--the usual fix is to pull back on spark advance in the ranges where the pinging is occurring, are not necessarily those normally considered as "beating on it".

This year I did not switch from my "OK" tune to my "Hot" tune, and just earlier this week the engine told me it was time to load the "Damned HOT" tune by pinging slightly under light, lower rpm (1800), acceleration.

Richening the mix can also correct the situation--what do your AFRs look like?

Do you have a wide band O2 sensor system? If not, why not? Running f/i without a WB O2 sensor is about the same thing as playing Russian roulette with a six-gun with four bullets loaded...

kongdong

I was told I didn't need one because the blower is a reliable. I do know that when my tune was done at mustang specialties in west palm beach they told me that they were going to make tune more rich than lean so that I didn't have anything to worry about.

cliffyk

Well then there's nothing to worry about...

kongdong

What gauges should I get other than a wideband air/fuel?

kongdong

I uploaded a video of my car so you can hear what's going on and what it sounds like. Some of the sound is faint so please try to listen carefully. If you know what this is than please tell me.

http://www.youtube.com/watch?v=eAhm_-tuDjg

v8.GT Stang

check maybe you have misfire and its time to change ur spark plugs

kongdong

My spark plugs were changed when I got the blower and that means that they're not even a year old. I had to get colder ones. I still remember like it was yesterday.