describe the sound

[Mustang Ricky]

ok, i'm trying to figure out the sound my engine is making. at first i thought it was a ping. now i'm not sure.

how does someone distinguish the difference b/w pinging and a exhaust leak? i heard the injectors can cause noise but i wouldn't think i would be able to hear them over the exhaust while accelerating?

the engine noise tends to be louder at lower rpm's but that might be because the exhaust sound is louder at higher rpm's thus masking the engine noise.

 

[Black331Stang]

u would definitley be able to tell the difference between exhaust leak and ping..ad ping is a ping sound and exhaust leak is more of a farting noise..like popping

 

[Mustang Ricky]

the sound is a more popping sound. it only present when the transmission is engaged and the car is moving. no popping noise if the car is in neutral and i rev the engine. when the car is moving, the popping sound does get louder as i press more of the gas pedal, and softer as I let up.

any ideas where the noise is coming from?

 

[BlackFox5.0]

Does this noise get louder as you go up hill? I think a ping sounds more like a ticking....

 

[Mustang Ricky]

if i go up hill, the sound does get louder. of course i'm pushing more on the gas pedal to maintain speed. i can hear the noise at lower rpm's, especially in 5th gear. as the rpm's increase, as does the exhaust noise so i'm not sure if the noise persists. i can typically hear the noise up to 2500-3000 rpms. the noise is worst when i try to accelerate in 5th gear around 1500 rpms.

 

[Look Its Aaron]

put some loose change in a coffee can, shake it around and that's what pinging sounds like.

 

[Mustang Ricky]

the sound is more like snapping fingers.

 

[Mustang Ricky]

i just got back from driving the car. the sound disappear when i let off the gas pedal plus there is a slight "tinny" sound to it along with the "finger snapping" sound.

any ideas?

 

[Look Its Aaron]

Sounds like the car isn't timed. The finger popping noise you hear might be backfiring through the intake.

What is the timing at now, and what grade gas are you using?

Are your plugs gapped right?

How does your cap and rotor look?

How old are your plug wires?

Just some things you might want to look at.

 

[jerry beach]

I agree, from the description it sounds like you have detonation. This is very bad for the motor and will cause damage if it is not stopped. do the things Aaron suggested. Run some 93 octane fuel and see if it goes away. Back off on the timing. Is it possible that the engine is loaded with carbon? does it get driven hard sometimes to keep the carbon cleaned out of it?

When did this prob. show up? Has it done it since you got the car, or after some work was performed on it? Knowing when something started can help you figure out why.

 

[Mustang Ricky]

the Mustang was a daily driver up until 2000. it has not become a daily driver again 8 months ago. this is when i notice the sound. btw, the car has around 145K miles.

I run with 93 octane and the timing is set to 10*. I will double check the timing. i did have the timing set at 14*. i have since backed down the timing. the sound is there, both at 10* and 14*, with no differences to the sound.

the plugs are gapped at .54. the rotor and cap were replaced a few summers ago, the plugs and wires replaced this last summer.

i guess i can pull a spark plug out and look at its condition. i haven't done that since i replaced them.

 

[jerry beach]

Reading the plugs is a great idea. If they are white, it may be a FP going out, or the pressure is too low. If they have chunks of carbon on them, that would be a sign of excessive build-up in the combustion chambers. This will cause detonation too. Chunks of glowing carbon can get left behind in there and ignite the fuel too early. Is the sound present when the motor is stone cold, or does it start after it gets warm? How hot is it running? Excessive heat will cause pinging too. Good luck.

 

[Mustang Ricky]

the noise is present when the engine is cold and warm. the noise has been occurring since summer and noise has not changed much during the beginnings of winter. the car has a new radiator, water pump and 180* thermostat. it runs very cool now, the 2nd line from the bottom.

in the past, when i have changed the plugs, then tend to be white. i know they're suppose to be a more tan color. i figure the car is running lean but it always has since i've owned it (10 years). could it be now with the combination of mileage and running lean, it's detonating?

how does one make the engine run more rich if the air/fuel mixture is controlled by the computer?

 

[ComfortablyNumb]

If the noise is a constant ticking or tapping sound its could be a header gasket. The bolts just randomly backed out of my passenger side header one day and it started making a tapping noise that gets louder and faster with RPM. I tightened the bolts back down and the sound was almost gone, but I think the gasket is blown now so I will have to get a new ones.