Morning all.... I recently bought a 2007 F150 XLT 5.4L with 108000 miles... I live in South Texas and on the second day in my ownership I drove it to New Mexico, love the truck, but there's a strong smell of antifreeze and the smoke/condensation (whatever it's called) coming out of the tailpipe is more than usual... Even after being on the road for 5+ hours it is still coming out at a good rate.. could this be the heater core, also the check engine light came up and it's reading bad O2 sensors... I'm assuming the 2 problems have nothing to do with each other, but I'm concerned more about the antifreeze smell and the amount of smoke (whatever) is coming out of the tailpipe... any help????

 

If your sure the smell is antifreeze, then I would think you might have a head gasket leak, let's hope not eek. Antifreeze may be getting into the combustion chamber. I would try replacing the O2 sensor(s) first, since the truck is telling you something is wrong there. Good luck

 

is your passenger side carpet wet under the dash, the heater cores are known to leak and could be the cause of the antifreeze smell. Is your coolant level dropping at all. Freeze plugs go bad to and can leak, sometimes they are pretty hard to pinpoint.

 

No there isn't any moisture on the carpet. The smell is mostly coming from the engine, I haven't pin pointed it yet.. and I would think I'd lose some power if the head gasket needs to be replaced??? I'm sure the antifreeze smell and "smoke" from the tailpipe are related.. like I said it's more than normal on a cold morning and as long as it's cold it'll come out all day even after the engine is warm..

 

I have to agree about the head gasket. I would get it checked out as soon as possible to be safe. Definitely keep an eye on the coolant level, and watch for bubbles in your degas bottle.

 

I'll get that head gasket checked in the next few days. Also I was told there is a 3 way connector near the firewall behind the engine in a tight spot that is known to leak (anyone know of this?)

 

If you suspect that antifreeze is leaking or being burned off (as you see smoke out of the tail pipe), then it must be low in the overflow tank. Is it?

Simple to diagnose; take it to a shop and have the coolant system pressure tested.