2001 f150 screw 160k 5.4L. I had the truck for 3 months and I started noticing what it sounds like an exhaust leak on the passenger side. It only ticks on cold start and the truck has to be in gear to be heard. If i drive a few miles the noise slowly goes away and it doesn't come back until the engine is completely cold(like let it sit 3-4 hours). I can hear it from the wheel well. I really don't notice it coming from the top of the engine.

Today I removed the wheel well cover and confirmed it is an exhaust leak. it is the last top bolt of the manifold. I believe it is stripped since it spins freely but won't come out. If put my finger close to that area and I can feel the air pulsating. I also sprayed spoapy water on the area and I can see the air bubbles(i did when it was cold so I know is not evaporation).






I have a question. There is two holes with treads above that area. I think if I can remove the head of the bolt I can get a short piece of steel make a hole on it and with a measured spacer I can get a bolt that fit the tread. The piece of steel or metal will be long enough that will tighten down the corner of the manifold and maybe stop the leak.

Anyone knows what size bolt goes in those holes?

I will try to remove the whole manifold next week at my buddy's shop but I think this will avoid me from doing it all that. I sprayed soapy water around and I didn't noticed any bubbles besides the area of the stripped bolt.

 

I went through this recently and decided to bring it to my local mechanic for the repairs. They replaced all the the studs with SS and also installed a new manifold since the original was warped. Total cost 330.00.

 

I don't think that will work and if it does not for long. Your best bet is to remove the manifold and replace the gaskets, studs, and nuts. Better off to fix it right than trying to rig something up.

 

you will find the gasket is cut / blown. Might as well that the manifold off. Look up the procedure and read about bolt removal. Son did it last year. Studs are stuck tight in the head and kind of surface welded to the aluminum. He was told to grind around the stud and into the head 1/16 inch deep to get the "weld area" out.... studs then back out with a pipe wrench. If you break off the stud during manifold removal, still do the grinding and you might get it to backout with a punch.

 

Thanks for all the replies. It was going to be a temporary fix but it only makes the sound for a few minutes until it warms up so I will just leave as it is until I can get to it sometime next week. I will go ahead and order a new gasket and SS stud set. I hope the manifold is not warped. I hope the free spinning stud comes off easy and that the tread in the engine block is not stripped. Could it be possible the stud is that corroded that it will strip the treads on the stud itself?

I heard it helps to warm up the engine for a few minutes before removing the studs and use some PB blaster. How long should I let the engine idle before I start?