2000 Ford Taurus, V6, Flex Fuel.

I changed out my spark plugs today, and noticed some antifreeze coming from the expansion tube. I recently flushed the radiator and refilled, wondering why the coolant level was low. If it was low, where was the leak? Couldn't find it. Until today.

The expansion tube is a metal tube. Goes from the intake manifold to a hose that connects with the expansion tank, or the reservoir tank. It runs under the manifold. I assume it is a metal tube instead of a hose due to extra heat by the manifold.

There was corrosion all over the expansion tube. It got wiggled a bit when I changed out the spark plugs. Now the leak is worse. When starting up the engine to see if it ran better (it did) and to move it into the garage, it leaked antifreeze all over the concrete. I assume it was a very slow leak until I wiggled the tube and made it worse.

Autozone and Pep Boys do not carry this part. Ford dealer does, but it is $97 and a special order as they do not have it in stock. I live in Los Angeles, so it's not a small town dealer either.

The expansion tube has a metal plate or mounting bracket on it to mount it to the manifold, and it also holds the EGR sensor plate bolted to the same place.

Has anyone ever changed one of these out? What would cause corrosion there? Haynes says if I do change it out, I MAY be able to remove it as is, but if I can't reach it properly, I will need to remove the upper manifold to get to it. That is a multi-step process that I'd like to avoid if I can.

If I do need to remove the upper manifold, do I need to replace the gaskets?

Question #2. When I replaced the spark plugs, I noticed a little oil on the outside of the plugs on the back plugs only, on the right two plugs only (right side of engine). Other posts online refer to a SHO Taurus, which I don't have. Possible oil on plugs include a leaking valve cover gasket. For the SHO, it apparently comes with spark plug gaskets or something different and weird.

No water in oil, so I do not suspect a head gasket leak.

Plugs with oil also had white/gray ash buildup on plug electrodes.

Car ran fine until I put some fuel injector cleaner in tank. Then it ran like crap for about half a tank. Smoother idle now. Then I replaced spark plugs and PCV and engine runs smoother yet.

Worries include...did fuel injector cleaner break something loose and make it run crappy? Just keep driving and that will go away? New spark plugs helped I am sure. Did running car low on coolant do any permanant damage? What causes oil on spark plugs?

Do I need factory expansion tube or can I do something cheaper? Can I repair the expansion tube?

Car has 65,000 miles on it. I bought it used with about 58,000 on it and I've maintained it well, but don't know history of previous owner.

Any help/suggestions welcome.

Mark in LA

 

Make it easy on yourself. Remove the upper intake and replace the gaskets. Corrosion and rust are always occuring in coolant systems. Perhaps the water that was mixed with the coolant was slightly acidic - or maybe a factory part had a speck of metal with slightly acidic properties - who knows? I do believe there is a compound you can add to your coolant now to prevent rustout and corrosion though. Also - use some engine paint on the outside of the new tube if it's unpainted. The tube can rust from either side - but you can have a major effect on mostly the one when it's bolted on. Most all spark plugs have metal washers that act as gaskets attached. A head gasket leak can also put oil or water out the tailpipe or combustion chamber pressurised air into the radiator or engine block. White plugs usually indicate overheating. Fuel injector cleaner can loosen debris in the fuel system. It may go away. Running low on coolant can cause permanent damage if low enough that the engine overheats. Oil on spark plugs can be caused by bad engine piston rings or bad valve seals, block/head fractures, fuel consistency, etc. but if you mean just on the outside of the spark plugs- leaking valve cover gasket is most likely. Factory expansion tube is probably your only (and best anyways) option (unless you're a qualified welder who can rig a nice thick tube that won't go bad). With low miles I recommend changing fluids and filters as the company recommends in the owners manual. If you keep with it you'll be ahead of the game if other problems arise. Also changing battery cables every few (3-5) years will keep electrical troubles away.