dragstart

Hate to start another potential sky-is-falling topic............but here goes.

My 5.0 seems to have a rattle, like a dull thudding, when it is cold. Starts at about 3,000 rpm with light load on the engine. Don't know if it continues into higher rpm or higher loads, didn't really experiment. It stops when the engine gets to operating temp, (temp needle straight up).

Anyone else perceive this? Is just endemic to this engine, or a potential problem?

assasinator

lots of folks have piston slap. its not supposed to do that with hypereutectic pistons.

YSUsteven

I have not noticed any noise when cold, but I also try to keep it under 2,000 atleast until the cams unlock (about halfway between cold and stright up).

dragstart

I had considered that the noise may be something to do with the cam timing system, because it only occurs under pretty specific conditions.

Arak-Nafein

Anyone else have this? I started noticing it not too long ago.

1969 Boss429

I have the same problem. Happens at exactly 3000 rpm until the engine is completely warmed up. No idea what is causing it.

born2run74

I have the same issue also, kind of a rattling. But it stops after 1 min of driving.

cdynaco

chain rattle?? is oil up to temp?

1969 Boss429

As soon as the coolant temperature gauge gets right in the middle it goes away. Oil pressure gauge remains in the middle as well.

Mine sounds like a rattle almost like a marble rolling around but only at 3000 to 3100 or so. Nothing above or below.

Arak-Nafein

^This. Sounds almost like a marble rolling around. But only in the low 3,000 RPM range & it goes away after the car warms up.

JobeNole44

I have this as well. Experienced no drop in power or any other noises, and it has not gotten any worse since I heard it several months ago. I just figured if there is a problem with these technologically advanced bad@$$ engines, my ECU will tell me via a check engine light.

1969 Boss429

Have any of you guys had any luck diagnosing this problem?

I ordered an intake and tune this week and wanted the dealership to take a look at it before I installed the new parts. They did not know what was causing it nor did the Ford representative they contacted. The dealership thought it might have something to do with the tensioner assembly but that would just be a guess. They told me they could either start taking parts off and diagnosing it or wait until they get another 5.0 with manual transmission on the lot to compare to as it may be something that is normal for the manual transmission 5.0s. I asked them to hold until they get another one on the lot in lieu of just taking parts off. But, by this time I will have my intake and tune installed.

I guess if they do solve the problem I would have to just re-install the stock airbox and flash back to factory. Any more thoughts or ideas?

Thanks

Modshack

That's not a real gauge...It's always in the same spot (either on or off....Might as well be a light)

1969 Boss429

Yeah that hasn't been a variable in it. However, it goes away once temperature gauge hits the middle. Just picked the car up and they really seem to think its normal for 5.0 manuals but don't have another one to compare it to yet.

Swoope

long thread on this issue here.

http://www.allfordmustangs.com/forum...art-drive.html

beers

2011GT/CS

This isn't true for me. When I turn the car off and turn key back on the oil pressure is down

shadowstang03gt

Quote:
Originally Posted by 1171stang
I can only assume that you're joking. An a/c comp is certainly not the culprit.

I registered JUST to reply to this thread. Im on a few other Mustang boards and own a 2011 5.0...

The knocking is most certainly coming from the a/c being the culprit. I cant begin to explain to you the BS flag i threw at the dealership only to swallow my pride in thinking i knew better not to be a sucker and not believe them.

Sure enough, the tech "cut the belt" off the car and the knocking went away, and then installed a new belt and the knocking came back at idle. the ford hotline told the dealer that "it is a normal characteristic of this high performace motor becuase there is no belt tensioner on this motor, and thus so, the a/c compressor takes all the load at idle cause the VVT to adjust and make a slight knocking noise"

I was told there is NO ISSUES to be had and its not going to hurt the motor. I too, hear it from the passanger side valve cover and also in the shift ****. I was told on another board that someone heard of ford releasing a tensioner for this motor to shut customers up who come in abou the noise.

After installing My magnaflow catback, JLT intake, and Evolution performance tune, the sound has disapeared / I dont hear it any longer. However, it still may be there becuase the cars rathe loud. Ill open the hood tommorow and check around the valve cover for you guys.

I seriously would not worry about this knock that was posted in that sound clip/ viedo. Every single 5.0 on my delers lot of 12 new 5.0's also made the same noise. that was enough + the belt coming off and not making the noise to ease my mind.

Quote:
Originally Posted by 1171stang
I can only assume that you're joking. An a/c comp is certainly not the culprit.

I registered JUST to reply to this thread. Im on a few other Mustang boards and own a 2011 5.0...

The knocking is most certainly coming from the a/c being the culprit. I cant begin to explain to you the BS flag i threw at the dealership only to swallow my pride in thinking i knew better not to be a sucker and not believe them.

Sure enough, the tech "cut the belt" off the car and the knocking went away, and then installed a new belt and the knocking came back at idle. the ford hotline told the dealer that "it is a normal characteristic of this high performace motor becuase there is no belt tensioner on this motor, and thus so, the a/c compressor takes all the load at idle cause the VVT to adjust and make a slight knocking noise"

I was told there is NO ISSUES to be had and its not going to hurt the motor. I too, hear it from the passanger side valve cover and also in the shift ****. I was told on another board that someone heard of ford releasing a tensioner for this motor to shut customers up who come in abou the noise.

After installing My magnaflow catback, JLT intake, and Evolution performance tune, the sound has disapeared / I dont hear it any longer. However, it still may be there becuase the cars rathe loud. Ill open the hood tommorow and check around the valve cover for you guys.

I seriously would not worry about this knock that was posted in that sound clip/ viedo. Every single 5.0 on my delers lot of 12 new 5.0's also made the same noise. that was enough + the belt coming off and not making the noise to ease my mind.