nails in a blender noise at high speed acceleration

[BladeX10]

I noticed if i gas it at 70 mph, A wierd noise starts and it sounds like a popping/nails in a blender sound and it sounds like its coming from underneath the car. I just started noticing it today. The car is an automatic 94 5.0. Does anyone have any insight on this?

 

[Venomous96Cobra]

if your car is running okay otherwise, and it is only making the noise at high speed and you have a stock h pipe... I would say that it sounds like you blew out your cat(s) you're probably going to hear that until all the catalyst material gets shot out of the exhaust!

 

[BladeX10]

Yeah i have a stock h pipe. It runs great otherwise. Pulls well and everything.

 

[Win]

Have you ever run your car low on oil to your knowledge?

 

[NXcoupe]

Sounds like detonation to me. More like a 'pinging' noise?

 

[BladeX10]

What would cause detonation?

It was low on oil when i first got it..

 

[BladeX10]

Think i found the problem.. I was sea foaming my car and noticed alot of smoke coming out from the mid pipe. Looks like it came loose or something and is making the noise. Ill tighten em up and call it a day

 

[NXcoupe]

Glad you figured it out. Too much ignition timing will cause detonation as well as a build up of carbon on the pistons and combustion chamber which causes the carbon to glow and ignite the fuel before the spark plug does.