Hey guys.... I haven't posted here in a long time, mainly because I haven't had any problems or extra money to spend on my truck... A couple weeks ago an odd occurrence started. At random times, not linked to speed, rpm's, or anything other than load, I get a loud clanking/rattling sound.

It seems to mainly happen under load, if I'm going a little slower than I should in whatever gear I'm in. Like if I'm in 3rd, only going like 15 or so (a little over 1000 rpms) it usually happens, but it also does it intermittently at idle sometimes and other times when going faster in a higher gear.

It sounds like it's coming from the rear of the engine/front of the tranny. It rarely goes on for more than a couple seconds, and then goes away. Cold or warm engine makes no real difference, except at idle. It never does it with a warm idle, but sometimes with a cold idle.

I really think it's one of my cat covers, but I can't feel any play in them at all. Could this be the dreaded CPS?

Any diagnosing tips?

 

it sounds to me like a loose exhaust heat sheild, but it's hard to say without hearing it myself

 

mine does that same thing and it fades out at maybe 1500-1700 rpm right??? it annoys the crap out of my... anyone please let us know. it could be the heat shield but i dought it since 2 ppl have the same thign

 

I have this too, drives me nuts! Normally it happens when I'm going up a hill.

 

Same problem, it was the heat shield.

 

my mustang was exactly as you guys described it, it was the front, right, cat heat sheild (1 of 8 cat heatsheilds on the car, 4 cats)