I have recently flushed the coolant system in my 2001 f150 with a 4.6, when I flushed the system I drained the radiator and block and took out the thermostat, I filled the system with water and drained again twice, while the water was in the system i ran the truck for about 5 minutes and I ran the A/C and heat to flush that out to. I replaced with fresh antifreeze and thermostat, and all seemed fine, but 2 days ago I started to notice a strong antifreeze smell from the A/C, and when i drove at night you could see a smoke in the cab when the smell was really strong. I dont know much about the A/C system so what do you guys think is going on? Any info or tips would be much appreciated.

 

Check for moisture - passenger side- under the I.P. Maybe the heater core sprung a leak.

 

ok ill check it over in the morning, the coolant level hasn't dropped and the hoses going into the hater core seem fine, if it is the heater core about how much will this set me back? and is it ok to drive the truck as long as i dont use the A/C system? and thanks for the quick reply Setchan

 

More likely you just have a coolant leak under the hood and the smell is getting sucked in under the cowling.

 

well i checked all the hoses inside the motor compartment and nothing was leaking, even during a 30 minute drive with the a/c not running you can still smell the anitfreeze smell with the windows rolled down.

 

Something is leaking or you wouldn't be smelling antifreeze...

 

i have driven the truck for a couple days and i can still smell the antifreeze no matter if the a/c or heat is on or off, the smell is the worst when the heat is on though, i would rather not replace the heater core but i think its the culprit here.

 

Your heater core has gone to see the big guy. Pressure test the cooling system and you'll probably prove that out.

 

2stroked is correct. A pressure test will answer your question.

 

well me and my dad replaced the heater core this weekend it took about 8 hours and it was bad i couldn't see any visible holes in it but there was antifreeze soaked in the bottom of the foam and on the sides. Thanks for all the help and tips you guys provided. If i can offer any advice to someone doing this is to take ur time and if you can just replace the heater core hoses too. I had to cut the heater core tubes to get it out because the quick disconnect tool wouldnt grab on the correct way and this was the easiest solution because we replaced it anyways and the tube ends we were able to get out once we pulled the hoses away from the firewall.

 

Glad we could be of some help in diagnosing the problem. Sorry we couldn't be there to help you replace the core itself. Well, sort of.

 

haha thanks 2stroked, it wasnt to bad of a job just time consuming but at least i know what my dash board consist of.

 

How do you pressure test the cooling system? Is this something only a shop can do? What will the pressure test result be if it is in fact the heater core? How much does the test cost?

Sorry to take over your thread with my questions:o, but I have been trying to confirm the heater core diagnosis myself in my 99 Expedition, 4.6L. I have the antifreeze smell when the heat is on and significantly reduced antifreeze levels. Today a large puddle of antifreeze developed on the ground under the passenger side, but not on the carpet or anywhere else inside that I can tell. The heater hoses under the hood do not appear to be leaking. Where else could the leak be to cause these symptoms?


Thanks so much for any help with this

 

There's a testing kit that one needs to have to run the test. It allows you to replace the radiator cap with a hand pump - that you use to pressurize the system. It's not something that most of us have, nor is it generally worth buying for one test. I'd recommend going to a shop. Some of them will do it for free - assuming they get the repair work.