Hello I have a 03 5.4 that has a miss mostly at what I would call a cold start (when it has sat awhile). My SES light is on and says misfire in #2 cylinder. I since have changed plugs, changed coil pack then I moved coil pack, and moved injector and the computer still shows missfire in cyl. 2. So after doing some reading on here I think I may have a Head Gasket leak. I went to look at some Bars Leak and there are several to choose from a couple that says it has aluminum in it even one that says copper. The copper one is the only one that specifically mentions Head Gaskets or is there another one that I havent found that I need to be looking for
Thank you for all your help and advice

 

Do you have any other symptoms of a head gasket leak?
Air in the cooling system,white exhaust,degas bottle with air bubles ect.

I would do a compression test and pressure test the cooling system first.

 

If you are using water thats a tell tale sign. If you have rough startup and then smooths out after a minute, that can be a leaking head gasket that drips into the cylinder after shut down.. THe coolant system can be 14 psi, and no pressure in the cylinder after shut down. I had that problem on old truck...........
If you decide you do have a head gasket problem and your loosing coolant internally, then i would use the COPPER bars leak that you add to the antifreeze. You dont need to drain, just pour into the top radiator hose, reinstall and run 20 minutes to pump it around and seal. You should see improvement after a day or so. My opinion was after shutdown, the 14 psi in radiator pushed the sealer into the gasket crack toward the piston and sealed the gasket overnight.

 

Bars Leak # 1109 --- about $10 a bottle.

 

steve I have all the symtoms you said how well did it fix yours and how long did it last ?

 

I would loose a quart of antifreeze every couple weeks. Ran fine all day long. Park and overnight a couple ounces would leak into #2 cylinder. Bad startup every morning that lasted 1 minute... then o.k. again. Temp gauge would spike and some puke of water if i let it go too long. I tried the drain and seal with clean water. Lasted for 8-10 months then needed to do again. I finally decided to try the COPPER which you add to antifreeze and it worked just as good. Sealed up immediately.. lasted 8 -12 months till i started seeing small problems again. Just added another bottle and back in business. After the second bottle, then i would drain, flush, refill with new antifreeze and add another bottle.. I did this for about 4 years and 50K miles.

 

My problems all started when i blew out an o-ring gasket on the intake manifold and overheated the motor on a trip towing to texas.. I had to limp home with various sealers. I changed out the o-rings and manifold gaskets, but not the head gasket (or a crack in head ?).... after the manifold gasket change i still had a minor problem. That is when i tried the BARS and got by for 50K miles. THen sold.