Originally Posted by JewelMarie

I'm a girl....yet I know more than the average chick about vehicles....I keep seeing these threads that talk about the same problem I'm experiencing...but no one seems to say what they discovered was the problem and how they fixed it? PLEASE HELP ME! Ok....here's what I have been going through with my 2000 5.4 f150....my first mistake....i let my dipstick bf borrow my truck one day and he overfilled her with oil....the next day I check the oil and it's halfway up the dipstick! I take her to jiffy lube...my second mistake...and ask them to do an oil change to get the levels back to normal...on the drive home I start to overheat! I pull over and look in the reservoir...to find that it's empty! One of the services of a jiffy lube oil change is to check that all your fluids are proper! So I'm pissed! I call and argue with the reject manager and after calling corporate they agree to bring her in for a full rad flush for their oversight....third mistake....taking my vehicle back to these A!!holes...they flush it and now everyday since....I'm losing coolant like its going out of style....no leaks or wet spots on the ground...I'm sure it's burning out from somewhere...although not a ton of white smoke from the exhaust so it's weird....also the other big problem is even after sitting all night...I drive my son to school. In the morning which is less than a mile away and halfway there my heater runs cold air ....suddenly i will hear this wwwhhhooooo sound and then the temp gauge goes up to a hair away from the H...then the air will change from cold to Luke warm and then the needle will drop rapidly down to the middle between c and h....????mso freaking confused....service engine light is on....she is also running very sluggishly probably due to the o2 sensor coming up on the code thingy and also code for cylindr 1 misfire is coming up too....I have changed all spark plugs as well as coil pack on cylinder 1.....i have also flushed my heater core....someone told me yesterday it sounds like I have an air lock in my cooling system and had me park on a hill and add water to reservoir until it bubbled and gurgled...it bubbled and gurgled but it did the same damn overheating scenario I explained above again! It's so strange....it almost seems to me like something is getting lodged somewhere and then finally blowing thru as the needle then drops? Does anyone know why there is a smaller oraface thing in the hose of the heater core? Could something be getting stuck in there? Can I safely take that thing out of there? Really need help here...I realize I may have blown head gaskets....but it seems like there is another problem here...wld the bad heads alone cause this overheating weird thing to be happening? I don't see how? Also can you lose coolant from an air lock? Seems the only way to lose coolant other than a leak is the head gaskets...ok I'm rambling now but if you comment here also let me know if you have known any our in head gasket sealer to work...and what brand...blue devil...bars...k and m...etc...thank you in advance for any info you can give me! One last thing...if you search overheating you will find a thread from a member named shifty who seemed to have the same problem...never did say what really fixed it....it just randomly seemed to stop after he got a new rad...? HELP!

Originally Posted by Carcrazygts2

A head gasket can blown and not leak into the oil. I drove mine with a BHG for a 1.5 before it started leaking into the oil.

Originally Posted by Fifty

The only for sure way to check for a blown head gasket is to have a shop sniff the cooling system for combustion gases with a 4 or 5 gas analyser. anything over 50 parts per million of HC (hydro carbon) indicates a head gasket,head or block failure. The reason it overheats is due to the high temp in the cylinders getting pushed into the cooling system. I perform this same thing on every car that comes in my shop that was overheating. Especially on ones with aluminum heads like yours, as they are sensitive to over heating. There is a product one the market thats called "Steel Seal" thats is designed for head gasket failure. It does work but is only a band aid and you will, sooner or later, have to replace your head gaskets.

Originally Posted by udderbrudder

Not sure if this helps you but here we go. If you are continuously getting air locks in the cooling system, you likely do have a leaking head gasket. The theory in the quote is actually correct. But there's a better way. I have a tool specifically for diagnosing this and it's never been wrong. It looks a bit like a coolant tester but it uses a chemical. Air is drawn out of the cooling system and bubbled thru a chamber containing the chemical. If CO2 is present, the chemical turns from blue to yellow.If CO2 is present-it came from a cylinder. Period. I bought this tool from Snap-On about 10 yrs ago and they still sell them. If a mechanic wants your business, you may want to insist that he gets it and does the test to ensure you don't spend a pile of $$$ for nothing. In my experience the test has been foolproof. Just a thought.
BTW I'm not a believer in "mechanic in a can". If your head gasket is leaking it needs to be replaced.