*Update* Took car to Ford for the diesel sound I was hearing..

[96BlackSnake28]

As predicted by some of you here...

Turns out puttin the UD pullies on ****ed up 3 out of my 4 tensioners and a crank sprocket...

They *think* this will fix the problem, however...one of the techs swares it isn't going to and that what I'm hearin is "piston slap"...and that I need a new bottom end...

Even with the discount I'm getting (Cost price on parts) and (Family price on labor)...I'm still getting raped big time...


I'm really hoping that this is my problem and is not the piston slap they were talkin about...

Think so?

 

[5.0's 4 ever]

I actually had the same problem you have right now with my original 96 motor. Put underdrives on about a month later it started to sound like a diesel. I ended up replacing all four chain tensioners myself and the sound was still there. I don't blame my pulleys though because they had nothing to do with my problem. The previous owner before me did not keep up on the oil change intervals and I found some oil sludge build up. Whatever it was the damage was already done.

 

[travis0712]

not keeping up with oil changes on a 96 mystic cobra, any car for that matter? what a waste! The 96 mystic was the car that made me want a cobra... back in 96 it was the top dog... nice wide 17" tires.... that amazing paint... I had an 86 GT then, it took me 6 long years to get one... it's not mystic... I couldn't wait any longer - fall of 2002, I bought my Cobra... I might own another one, but I will never get rid of this one..

 

[96BlackSnake28]

I actually had the same problem you have right now with my original 96 motor. Put underdrives on about a month later it started to sound like a diesel. I ended up replacing all four chain tensioners myself and the sound was still there. I don't blame my pulleys though because they had nothing to do with my problem. The previous owner before me did not keep up on the oil change intervals and I found some oil sludge build up. Whatever it was the damage was already done.

So did you do anything to fix the sludge? How did it run performance wise after you changed the tensioners?

 

[5.0's 4 ever]

Yes I was suprised that the people did not keep up on the maintenance considering how rare the car is. They were not mustang people though, the wife used it for a daily driver and it was in need of serious wax job when I bought it.

With the sludge I tried running a little mix of trans fluid with motor oil and it did nothing. The only way of getting it all out was to tear the motor down to a bare block and have the oil passages cleaned. I was also not sure in where all the sludge was. I found some in the left primary chain tensioner when I was replacing them all. I was hoping that I had found my probelm but the engine still sounded like a diesel after I started it up. The car still ran just as good but it sounded like complete crap and was I pretty much embarrased by how my cobra sounded like a powerstroke at idle so I parked it and planned my engine swap.

 

[96BlackSnake28]

Yes I was suprised that the people did not keep up on the maintenance considering how rare the car is. They were not mustang people though, the wife used it for a daily driver and it was in need of serious wax job when I bought it.

With the sludge I tried running a little mix of trans fluid with motor oil and it did nothing. The only way of getting it all out was to tear the motor down to a bare block and have the oil passages cleaned. I was also not sure in where all the sludge was. I found some in the left primary chain tensioner when I was replacing them all. I was hoping that I had found my probelm but the engine still sounded like a diesel after I started it up. The car still ran just as good but it sounded like complete crap and was I pretty much embarrased by how my cobra sounded like a powerstroke at idle so I parked it and planned my engine swap.

Well I'm really hoping I don't have somethng like that...

Cuz it didn't make this noise UNTIL I put the UD pullies on...