[gills99stang]

So, I was going to pick up a friend from base the other day, and was on a long straight stretch of highway around 10 PM... if you live in Hampton Roads you'll probably know exactly which highway stretch I'm talking about (hint: Norfolk Base). As usual, there was no traffic at this time of night and I did my usual thing of taking the stang up to about 130 mph. No problem. Lot's of road, plenty of time to get it up there and slow it down afterwards. I just took it up to 130 and brought it back down easy.

When I got off the highways and slowed down to about 40 mph, I noticed a slight rattling/clicking sound coming from the engine area of the car. My immediate reaction, of course, was "Oh crap, what's broken." Immediately upon hearing the sound I drove very carefully, and once I got onto base, I stopped the car, left it running, and popped the hood to try and figure out exactly where the sound was coming from. The sound seemed to come from more under the car... it seems bad at this point because it sounds like a knocking noise coming from the lower part of the engine.

Now, to note: it only makes the sound when hitting the gas, whether in gear or in neutral, at a dead stop or going down the road. Also, after the night it first appeared, I let the car sit in the driveway for a week before pulling it into the garage to jack it up and crawl under the car to do a visual check. When I started it to put it in the garage, no more knocking sound. Jacked it up, nothing unusual under the car.

I took it for a test drive, and no sound. BUT, the sound slowly appeared after the car warmed up a little bit, probably after 4-5 minutes of easy driving.

So any suggestions? It sounds bad to me, a knocking noise coming from the lower part of the engine can't be good. Seems like I'm going to have to take it into a shop and get it torn apart.

I was about to get the oil and filter changed, it's about time for that... but I don't want to do that while I have this problem. I'm not about to try and just make this knocking noise go away with an oil change, and since I use synthetic, oil changes aren't that cheap.

At this point I'm thinking it's a lifter, rod bearings... what? Whatever it is, I know I need to get it checked out. I'll probably take it into MAS soon.

Input?

[ChrisJ]

Could it possibly be an exhaust leak?

[gills99stang]

An exhaust leak would make a rattling/knocking/ticking noise?

[gills99stang]

btw, when do you come back?

[sonicblue]

an exhaust leak could def make a ticking noise. hopefully thats what it is since it would be an easy cheap fix. good luck getting it worked out

[gills99stang]

So, should I take it for a spin, let it warm up, then jack it up again and try to figure out if it's an exhaust leak while the car is running?

I love having a nice big two car garage with a floor jack and jack stands... want to use 'em!

[TrueBlueGT01]

I wish you luck on that.. But... Usually any time I have ever had an exhaust leak it was worse when the engine was cold. I guess the expanding metal slightly closed the gap upon heating.

[Invictus]

i doubt its exhaust.. it would be even more obvious when its cold. i just installed the bbk longtubes and stupidly used the cheap fiber gaskets from BBk ... its more of a feathery hissing kinda noise than a tick. and it would most definatley be audible when the engines cold so i'd rule that out and save you some time and money

[Invictus]

if you still want to try it out, get a friend to hold some towels in your exhaust pipes and give it a little gas if it gets worse than you may check the the exhaust gaskets but id be willing to bet money thats not your prob

[gills99stang]

OK, probably not exhaust then... any ideas from anyone else?

[FOR POINT SIX]

An exhaust leak can sound like a valve tick all the way to a rod knock. But I would change the oil and check it for metal shavings, this will help in finding out if its in the engine.

[gills99stang]

OUCH.... metal shavings.... just hearing those two words makes me cringe.

[ChrisJ]

Originally Posted by gills99stang An exhaust leak would make a rattling/knocking/ticking noise?

Yeh it could...

Take some towels and put then in the tail pipes...Have omeone rev the car and see if you can hear the leak...If you can get to a lift it makes this alot easier...

I get back sometime in January hopefully...That is what is being said at least...

[superbeef1000]

inspect the ac clutch i had a problem like this once

[superbeef1000]

id say the bast way to check for metal in the oil system would be to change the oil filter and cut open the old one and look at the filter its self for shavings

[gills99stang]

Originally Posted by superbeef1000 inspect the ac clutch i had a problem like this once

huh???

[ChrisJ]

Originally Posted by gills99stang Originally Posted by superbeef1000 inspect the ac clutch i had a problem like this once huh???

He is talking about the A/C unit...The cluth on it is what lets it free-spin when you are not using the A/C...

[gills99stang]

So that could be making the ticking sound?

[ChrisJ]

It could be but I doubt it...I would check for exhaust leaks...

[AtxStang]

I had my AC clutch start to go out, it was a rattling noise that only sounded when the AC was off. When the magnet engaged the sound went away, but I replaced it anyway just in case. But the sound was coming from the front of the engine and you would have noticed this by now if it was your AC clutch.

Maybe take it to have a compression check? I don't know if that would detect the problem, but try the exhaust thing first, then check your filter for shavings like the man said, then if you still can't figure it out drop your pants and take it somewhere.