Anyone had this happen?

'03 250SD, SC, 5.4l, Auto, K&N, FM Series 50...about 7000mi.

For the second time in many weeks, I'm standing at a light, in "D", hear a LOUD BANG or THUMP.... loud enough to transplant my ********* up next to my adams apple.

Felt the reverb in the floor board.

At first, it sounded like I was hit.

Spring issue???? i.e. "popping back into place" ??

Almost sounded like a "detonation" in/near the catylitic converter.

Scared the $%^& outta me. TWICE !

HELP !

 

Had you just started the truck? Do you know what the A\C mixer door sounds like when you start the truck with the air on? I remember the first time I heard that I thought I had been backed into.

Matt

 

Had you just started the truck?

Yes... minus 1-3 minutes


Do you know what the A\C mixer door sounds like when you start the truck with the air on?

Yeah...seemed a LOT louder than that, though. Matter of fact, had just turned AC on. I try not to make it a habbit to start the car with the AC on.


I remember the first time I heard that I thought I had been backed into.

Yep... that's what it sounded like.


Could be..... I guess...I will also say it is a cure for constipation...

 

My 2001 V10 does it as well. I can assure you it isn't the HVAC system, that is more of a hollow pop from the firewall area. The sound described by kraut is feels and sounds like soneone hitting the passenger side floor with a rubber mallet. Mine only does it once in a while, usually when it is cold, and always within a couple minutes of startup. I'm not sure what it is, but in nearly 3 years, It hasn't caused any noticeable trouble.

 

I know what you mean, sometimes mine still catches me by suprise. Seems like there should be a fix for it. That and high blood pressure... I may have a lawsuit!

 

A/C mixer........scares the bejeezes out of me every time..........but i am a paranoid kinda guy in the first place!....that thhhwummp sound almost like what the f!@#$%^k was that kinda sound....what blew up....what i do wrong now?...............

d/ft

 

MY A/C mixer does the same thump although it isn't loud enough to make me jump.

 

Interesting.....sounds like a trend.....

Well, now all they need to do is to sell the truck with a good fabric cleaner to get that brown stain off of the seat

Glad it's nothing more......

Thanks for all the input.

 

I had to laugh when I saw this thread...my truck has been doing this since day one. It happens when the truck is already warm, you shut it off for a few minutes, then restart it, takes about 10-45 seconds. 6 yes 6 times it has been to the dealer for an ongoing PINGING problem and while it is there I mention this to them. I firmly believe it is not the AC flap as I hear that noise as well, like someone described near the firewall. As also described the particular sound is that of a mallet hitting the passenger floorboard. It's an ongoing joke with my friends, when my truck makes the noise I say "did you hear something?" and the response is "no I didn't hear a thing" in a sarcastic tone. Must have to fail a hearing test to be a ford dealer mechanic. The first five times the dealer reported no problem found, that is until last week, when the manager of service department agrees to go for a ride with me and my trailer, to beat up my rod bearings a little more and listen for the ping. Just after I start the truck I see his feet fly in the air and about hits his chin with his knees and he says "what was that!!" And of course I said why did you hear something? After he collected himself he tried to tell me it was the AC vent flap, but it already made that noise. So in the end I still don't know what the noise is, My truck still pings everyday, and yes I am researching the lemon laws after 35000 miles of pinging every single day.

 

My wife complains about that thump all the time.