Slight banging from floorboard. Please advise.

[Alley]

Just in the past week I've begun to notice a slight banging I can feel in my feet on the floorboard and hear. I generally only feel it at idle and mostly on cold startups. And I really get a good bang when I shut the car off. Engine or Tranny mounts?

I was planning on doing poly mounts this winter anyway becuase I do get quite a bit of noise when I shift at low RPMs. I've always dismissed it as viper driveline slap but maybe its been the mounts as well?

 

[Kevan]

It's the Corvette you ate at at the track a few weeks ago.
You can get him out of there now.

 

[past ohio]

Probably the quick change oil guy got stuck under there...let him free !!!!!

 

[HPmopars]

Just in the past week I've begun to notice a slight banging I can feel in my feet on the floorboard and hear. I generally only feel it at idle and mostly on cold startups. And I really get a good bang when I shut the car off. Engine or Tranny mounts?

I was planning on doing poly mounts this winter anyway becuase I do get quite a bit of noise when I shift at low RPMs. I've always dismissed it as viper driveline slap but maybe its been the mounts as well?

Does it make a difference with clutch pushed in or out?

 

[plumcrazy]

mine did this last year. it was the header hitting. it didnt look like it would when it was on the lift but it was.

 

[jmillsUT28]

Change your engine and trans mounts... ?

 

[Viper Wizard]

I'm leaning toward the exhaust hitting too? Check your right motor mount where it bolts to the frame. There is no "deadman" on the right ones so under hard deceleration the mount will creep up and make the exhaust hit. If that's the case, just loosen the MM nut and with a pry bar push the motor back down to the bottom of the slot, then tighten the nut. See if the noise is gone.

 

[Alley]

Its the exhaust. Its hitting on the drivers side where it turns into the sidesills. On the passenger side I can fit a finger underneath the pipe, and on the driver side its practicly sitting on the frame. Havn't taken off the side sills yet. Is it likely I broke a hanger? Or could it still be a issue with the engine shifting cause of a bad motor mount?

 

[RTTTTed]

put a 2x4 under your oilpan and gently jack up the engine. Everything in good shape would lift the car off the ground, but I don`t recomned that much pressure. Jack to take up the slack and then apply a little pressure. If a mount is broken then the engine should lift off of a broken motor mount. Use a prybar and try to lift the trans off the mount.

Usually any engineétrans movement can be felt when the shifter moves all over the place.

Ted