Possible exhaust manifold leak?

[Fire488]

I have another post in here regarding some other problems that I seem to have, but I'll throw this out there as well.
2007 Ford Explorer Limited V8
When the truck is started cold I hear what sound like an exhaust leak emanating on the right side near the manifold. I cannot be sure of that, but it is coming from the right side that's for sure. It is a ticking sound that increases with RPM's and disappears after 10 seconds or so. The sound may also be coming from the right bank of fuel injectors too. I cant be sure if it is a mechanical tick or exhaust leak. It has been doing this for about a year and is not getting worse. It is not a lifter tap either, that I know.
Any ideas where to look here?
This only happens when the truck is started cold and after warmed up i can shut down and restart with no noise. When warmed up the truck is completely quiet.

 

[striker5427]

I had the same thing happen to me a few weeks ago: Exhaust Manifold leak. 2 studs broke and warped the manifold. Fix: replaced manifold and studs under power train warranty.

 

[Fire488]

I had the same thing happen to me a few weeks ago: Exhaust Manifold leak. 2 studs broke and warped the manifold. Fix: replaced manifold and studs under power train warranty.

My truck is a 2007 and has 120k on it. I'm not sure if a warranty applies here anymore. I'll check.

 

[Fire488]

OK well the manifold is definitely leaking when the engine is cold and then stops almost 25 seconds after running. I have noticed a reduction in power and fuel economy so i guess i will have to change this manifold. The warranty no longer applies anymore.
Does anyone know the exact part numbers needed and an R&R procedure that would not require complete engine removal? Are headers a possible option for added power and increased exhaust flow? I cannot find many options for the exhaust on this explorer. My vehicle specs are listed in my under my name.

I have been starting to get codes and check engine light related to "faulty catalytic converter" due to this manifold leak. I have been told that this code is directly related to the leaking manifold.

Thanks

 

[Flag Gibby]

For the three valve 4.6 L engine no aftermarket manufacturers have a listed part yet, but someone over in the modified section is attempting to use the mustang 4.6L three valve aftermarket manifolds. They are going to have a speed shop do the work and provide a custom tune in order to get the full benefit of the aftermarket manifolds.

 

[Fire488]

Yeah I see there are a few out there trying it. I found a few sites that offer Headers and CAT back systems. I was thinking about doing this rather than going with the stock setup again since nothing has changed and they will surely leak again. I think I could fix the issue with the use of over-sized helicoils since the root of the problem appears to be that the studs are not strong enough for the task of clamping these manifolds down. I guess the expansion and contraction is too much for them.
I will keep digging until the right solution jumps out at me.

Funny thing this issue is one of many on a list of problems. Most have been fixed, but new probs keep emerging. I know I need a radiator (for 2 years now) and complete brakes. I changed the front hub assemblies. The new prob i have now is that every time it rains my anti-lock light comes on as well as the stability control light. once the rain stops the light goes out. Also when it gets warm out the check engine light stays on. When it is cold there is no light. The engine runs at proper temp no matter what the ambient temp is. Still digging...

 

[jseabolt]

I noticed my '06 is doing the same thing.

Not suprising my '96 5 liter was doing this but in that case it got worse. The exhaust manifold on the passenger side cracked right in the middle. What a PITA to replace.

Getting the manifold bolts off was the easy part. The bolt/nut that secures the downpipe to the exhaust manifold on the engine side took me about 4 hours to loosen because I don't think it had ever been loosened since it left the factory. So I couldn't get enough torque on it due to clearance issues.

Because the manifold had separated into two halves, I was able to loosen the outer bolt/nut and rotate the rear half enough to where I could get to the other nut/bolt. Otherwise if a person had to remove the exhaust manifold for any other reason I don't know how it could be done.

I know this doesn't apply to the modular engines, and hopefully it's not as bad as the old smallblocks. At least changing the modular engines don't have plug wires and coil packs! That was another all day job.

Wonder if the exhaust manifolds on the modular engines are bad about cracking in half?

 

[JPinUSMC]

My 06 Limited had the same problem. Took it to a shop and the headers had to be resurfaced because they were warped. I had them put copper header gaskets on and that didnt fix the problem.

I went online and found these gaskets a short time later and installed them myself after the shop dealt with the bolts.
Percy's dead soft header gaskets

The only thing with these gaskets is you need to go in 3 times and tighten them which can be a pain, but once you've done it a time or two its pretty quick.