Cold Start Noise

[14GT5HUNDRED]

I remember a thread a while back about people speaking about a rattle at cold start up.. I just saw this come across the wire today at ford tech site.. thought I would post.. I know there was a thread and probably should search.. sorry.. but here it is

Apr 11 2016 2888 - Some 2016 GT350 Mustangs Might Exhibit Piston Rattle From Idle To 3000 RPM

Some 2016 Mustang GT350 equipped with the 5.2L engine may exhibit a rattle or rapping type sound during cold operation at light loads and speeds from Idle - 3000 RPM. The noise will be most noticeable during light acceleration in the 1500-3000 RPM range and may also be noticeable in the 800-1200 RPM range with neutralthrottle blips. This sound is caused by the piston motion in the cylinder bore.This is an inherent characteristic of the forged aluminum pistons utilized in this high performance engine. Once the engine reaches operating temperature the noise will diminish, although it may still be noticeable even when fully warm. There are no durability concerns with this sound.

 

[DieselDr]

I hear this on my car every morning when in normal exhaust mode. I figured it was piston related because it does not stay consistent like valve train noise. It is absolutely load sensitive. Good to know I can stop worrying about it.

 

[ObieFox]

DieselDr,
Can you clarify what you mean by "absolutely load sensitive"? Forged piston slap is generally at cold temp and as the bulletin says under "light loads". Any "rattle" under heavier loads is generally not slap and most likely detonation.

Kevin

 

[CO Mack]

DieselDr,
Can you clarify what you mean by "absolutely load sensitive"? Forged piston slap is generally at cold temp and as the bulletin says under "light loads". Any "rattle" under heavier loads is generally not slap and most likely detonation.

Kevin

In mine, any acceleration and it's gone. But sometimes at idle and coast down you can hear it, hot or cold. It is exactly as described in the OP.

 

[liter of cola]

I just hate quiet mode on these cars... Sounds friggin horrible. I wanna get rid of that shit.

 

[SID297]

Forged pistons with low tension rings, piston slap is not unexpected.

 

[DieselDr]

DieselDr,
Can you clarify what you mean by "absolutely load sensitive"? Forged piston slap is generally at cold temp and as the bulletin says under "light loads". Any "rattle" under heavier loads is generally not slap and most likely detonation.

Kevin

My car only seems to do it from about 1500-3000 rpm. If you give it some gas it goes away. Only does it under very light throttle.

 

[01SVTSnake]

Definitley hear it on mine when cold backing out of the garage