Loud bang on startup and loud tapping sound from the top of the engine

[MustangLife]

I started my car up 2 days ago to leave and it made an explosion sound from the engine and smoke came from the under the hood for about 5 seconds. Now I have a loud tapping sound thats coming from the engine and you can feel the tapping on one of the coil packs. Like its hammering on it. Its really damn loud, the car is still running, i started throwing a code about a week ago. Is it as bad as i think it is.

Josh

 

[Andrew_5.0]

Josh--

I hope you still have a warranty on your car.

I'm pretty sure you blew a plug right through the danm head. Not literally, but the plug might have misthreaded itself and F'd everything up. If that is the case, new head and new coil pack assembly.

It happened to me-- and thats what I thought. THen, FOrd verified it and luckily it was under warranty.

Let us know what happened. Take it in. Or, rip it apart yourself, and take a look.

 

[stangr66]

Yep, sounds like ya blew a plug outta the cylinder head. I've repaired a 5.4 engine that did this with a heli coil, alot cheaper then replacing the head and it's still runnin. Might condsider it when ya go to fix it.

 

[Kilgore Trout]

No no no helicoil...

15815
Do not repair spark plug port threads in aluminum cylinder heads-
Unapproved usage of helicoil for serice
Some engines equipped with aluminum cylinder heads may exhibit spark plug port(s) with stripped or missing threads, "Do not" service stripped or missing spark plug port threads by using "helicoil" or "tapersert" repair kits. It is likely that additonal engine damage or engine failure will occur after an unsuccesful atttempt to service the cylinder head spark plug reports with "helicoil" or taperset. The only authorized service procedure is to replace the cylinder the cylinder head assembly when spark plug port threads are damaged is to replace the cylinder head assembly when spark plug port threads are damaged and in need of service, refer, to the pertinent workshop manual (section 303-1) for cylinder head removal and installation procedures. Note: When servicing spark plugs for any reason , do not use air or powertools and take care to ensure that spark plyugs to not crossthread.

 

[SeanD1111]

No no no helicoil...

15815
Do not repair spark plug port threads in aluminum cylinder heads-
Unapproved usage of helicoil for serice
Some engines equipped with aluminum cylinder heads may exhibit spark plug port(s) with stripped or missing threads, "Do not" service stripped or missing spark plug port threads by using "helicoil" or "tapersert" repair kits. It is likely that additonal engine damage or engine failure will occur after an unsuccesful atttempt to service the cylinder head spark plug reports with "helicoil" or taperset. The only authorized service procedure is to replace the cylinder the cylinder head assembly when spark plug port threads are damaged is to replace the cylinder head assembly when spark plug port threads are damaged and in need of service, refer, to the pertinent workshop manual (section 303-1) for cylinder head removal and installation procedures. Note: When servicing spark plugs for any reason , do not use air or powertools and take care to ensure that spark plyugs to not crossthread.

That is total BS. People use the Timesert, and Bigsert on the 5.4 head all the time due to plug blowout with no ill effects. Even dealerships will install the kit. Of course a manual (especially Ford) would say do not do that, spend 10x more for a new head.

 

[Mike97gt]

No no no helicoil...

15815
Do not repair spark plug port threads in aluminum cylinder heads-
Unapproved usage of helicoil for serice
Some engines equipped with aluminum cylinder heads may exhibit spark plug port(s) with stripped or missing threads, "Do not" service stripped or missing spark plug port threads by using "helicoil" or "tapersert" repair kits. It is likely that additonal engine damage or engine failure will occur after an unsuccesful atttempt to service the cylinder head spark plug reports with "helicoil" or taperset. The only authorized service procedure is to replace the cylinder the cylinder head assembly when spark plug port threads are damaged is to replace the cylinder head assembly when spark plug port threads are damaged and in need of service, refer, to the pertinent workshop manual (section 303-1) for cylinder head removal and installation procedures. Note: When servicing spark plugs for any reason , do not use air or powertools and take care to ensure that spark plyugs to not crossthread.

your right about the helicoils. well kind of sort of. IF you can get it too work the helicoil should be fine. especialy if it's in a non high performance application. Ford issued that ssm because a lot of times there is piston damage or valve damage. plus the metal shavings from the helicoil repair can cause more damage.

anytime you do plugs on a modular motor use some locktite. ford recomends this for the lightings already. don't worry about the plug seizing in. we have aluminum heads they don't seize in like the old cast heads.

someday ford will redesign the head with extra threads to stop this problem.