So over the past two days i changed out the heater coil on my in-laws truck...first off its a 2001 f150 4x4 with the 5.4. They told me about what was going on and that they ordered the parts so i went ahead and tore into the truck and all i can say is wow, what a job. Now i have it back together and the truck now has a water rushing sound coming from the heater coil box area. It begins to make the sound around 1800 rpm's to 2800 rpm's. I've gone through the forum and came across some things like coolant on the ignition coil and causes rough running but the truck doesn't seem to have lost any power and the water rushing sound its throwing me off. If anyone has had this problem please help i really need to get this thing fix asap being that ill be leaving shortly

 

What is a heater coil? If you mean heater core, then it probably has air in the system causing the noise.
Usully parking on an incline with radiator higher and the cap off will let it burp itself.

 

Yea, bleed the system properly.

 

Yes i did mean the heater core... Ive tried bleeding the system multiple ways and have yet to get it go away. I looked at other post and have heard that aftermarket heater cores have a "restrictor" of some sort. has anyone heard of this said "restrictor"?

 

The restrictor is on the inlet pipe, they actually added them to factory ones with issues. Basically the water was coming so fast into the heater core, and it didn't want to turn the corner and would blow out the top of the Heater Core