Pinging and detonation

95CobraStang

Member

Jan 21, 2004

281

1

18

Chico, CA

Jul 17, 2004

#1

• Jul 17, 2004

• #1

I'm pretty sure I have never heard my car ping...so, with that said, i have no idea what it sounds like. Is it loud?? Is it quick and in even intervals?

I figure i should know this, since i have the predator and it is changing fuel and spark advance and i only have 91 octane.

If anyone could describe, that would be great.

thx

 

DBMSTNG

I fantasize about it being BIG!

Founding Member

Apr 23, 2002

2,120

0

56

not quite here

Jul 17, 2004

#2

• Jul 17, 2004

• #2

it can be loud or quiet, but usually you'll feel it if it's bad.

 

3

3.8L_of_Pain

New Member

Jul 4, 2004

123

0

0

Southern California -- Orange County

Jul 17, 2004

#3

• Jul 17, 2004

• #3

It is kind of a fast, popping, crackling sound coming from the engine compartment. Sort of like Rice Krispies cereal: Snap, Crackle, Pop. Not a technical description, but you probably get the idea.

 

J

Joel's98GT

New Member

Jan 3, 2004

368

0

0

central OH

Jul 17, 2004

#4

• Jul 17, 2004

• #4

3.8L_of_Pain said:

It is kind of a fast, popping, crackling sound coming from the engine compartment. Sort of like Rice Krispies cereal: Snap, Crackle, Pop. Not a technical description, but you probably get the idea.

Click to expand...

good discription.

to original poster, have you ever been in a vehicle going up a hill at low RPM and it starts to bog down, and makes the sound discribed, but as soon as you down shift it goes away? i'm sure you have. that's detonation.

 

twogts4us

15 Year Member

Apr 1, 2004

4,188

12

79

Dunedin, FL

Jul 17, 2004

#5

• Jul 17, 2004

• #5

BBs or marbles in a tin tan, shaken repaidly...
If you hear ANYTHING from the engine after messing with timing, this would be it. You also lose power as this happens, but it's not dramatic (like when TC kicks in).
If you can visualize, as the piston is coming up during the compresion cycle, the A/F mixture ignites too prematurely and sends a sonic wave down the cylinder, essentially rattling the piston in the cylinder wall. Scary huh?
Increased octane decreases the votility of the fuel, therefore it's often prescribed for and effective in preventing detonation or pre-ignition.

 

C

ChrisWorrell

Member

May 29, 2004

112

0

16

Alpharetta, GA

Jul 17, 2004

#6

• Jul 17, 2004

• #6

that is a very scary explanation of it

 

95CobraStang

Member

Jan 21, 2004

281

1

18

Chico, CA

Jul 17, 2004

#7

• Jul 17, 2004

• #7

Joel's98GT said:

good discription.

to original poster, have you ever been in a vehicle going up a hill at low RPM and it starts to bog down, and makes the sound discribed, but as soon as you down shift it goes away? i'm sure you have. that's detonation.

Click to expand...

Ahhh i see. I've definatey heard that before. Thanks everyone for the descriptions as now ill be ready to diagnose a little detonation now.