Friggin leak, can't pinpoint

Goldmember · May 24, 2013

Symptoms:
-Ticking sound that changes with engine speed (faster ticking with higher RPM)
-Worse when cold, goes away a little when engine warms up
-Once warm, you can hear the ticking under load (eg 4th gear, 40 mph, slight incline)

I'm aware the Crown Vic/E and F-series guys all have issues with exhaust manifold studs giving up the fight. In each of those cases the studs are exposed to the elements more than the Mustang.

The ticking can't be heard from under the hood.

Ideas? I'm thinking a flange is giving up the ghost or a weld cracked somewhere.

ttocs · May 24, 2013

Check your header bolts and your spark plug wires. Loose headers will do it and a bad/loose plug wire can also do it, just tightened up my header bolts last week to stop mine.

Goldmember · May 25, 2013

ttocs said:
Check your header bolts and your spark plug wires. Loose headers will do it and a bad/loose plug wire can also do it, just tightened up my header bolts last week to stop mine.

No wires on the '04- coil on plug ignition from 1999-on. Now that you mention it, got me to thinking I'll check the plugs themselves. These mod motors love to change their own plugs- not enough threads in the head and they back out over time.

I'm praying it's not the manifold studs (car has stock exhaust manifolds). They're notorious for failing on Mod motors. Listen to E-series vans or F-series trucks with the 4.6/5.4 as they drive by, if you hear a loud tick it's because the studs failed. Cheap crap.

No time or $ to drop the K-member for that, you can't do it from up top on a 4.6, motor is too wide.

Goldmember · May 26, 2013

The tick is getting significantly louder now. Part-throttle, light load, first thing at startup. It goes away somewhat as the motor warms up. Starting to think manifold, now. My old '85 Cutlass did the same thing.

I could try to tighten the manifold studs but they'll most likely break. Cheap metal and notorious for rotting away.

ttocs · May 26, 2013

I would say to check them out at least. 3 weeks ago I had a ticking and found one of the nuts had come off of the headers completely and 2 others were really loose.