Twice in about the past two weeks I have heard a very noticeable pop or bang when starting my truck. I start the truck and hear a bang that is almost as if someone threw a baseball and hit the truck. I haven't noticed any difference in driving it before or after this happens and no idiot light comes on.
The truck is a 2005 with about 33k miles.

Any ideas what could cause this or has anyone else had this problem? Because it has only happened twice I am afraid that when I take it to the dealership they will simply tell me they were unable to duplicate the problem after having it for a couple days.

 

Not sure if we have heard the same thing or not.....But I have an 04 F150 4.6 and if it sits for a dayor so and I go to crank it up it makes a "hiss" sound... like someone opened an AirHose under the hood for a split second.... Never noticed any trouble... no idiot light... 59,000 miles and havent had a single bit of trouble with it! Only does it once in a blue moon...

 

i know exactly what you are talking about. mine has done it a few times but went away by itself.

 

Thanks for the replies!

 

Mine has done it a few times. First time it scared the **** out of me. I though someone had ran into me or something. No problems from it though but it does bother me. It sounds like it might be in the drive shaft or around that area.

 

I would get it in the dealer and get it docummented before your warranty runs out...

 

I had a mitsubishi that did that. It was the ac compressor clutch engaging for the first time after sitting for a while.

 

Bingo! Thats exactly what it is. My tech buddy showed me that. For some reason Ford has the ac compressor engage on start up...to lube it maybe? I thought no way but had him start it while I looked down at compressor. Sure enough, even though ac was off the compressor engages for a few seconds on start up.

 

Mine has never done that yet. MAybe it could of been an intake backfire?


James