phrosty

When I press the gas pedal down and accelerate a little... give it a little gas... and let off the pedal, there's an obvious pop about a half a second later. It feels like it's coming from under the DS floor mat. Doesn't matter if it's from a dead stop, or coasting down the road and I gas it a little.

Anyone had a symptom similar to this?

Hondaddict

I have heard this too on my 07 but its very intermittent will happen a couple times then won't happen for months. Haven't figured it out yet

XLR8R

It could be related to the solenoid operated, vacuum driven turbo management, but there's a much greater likelyhood that the engine air filter might be dirty. This can cause popping and stuttering acceleration.

Mr Marco

could be something as simple as this:



Have you stuck your head under the dash/wheel to see if there is anything getting hung up?

-Or it could be a tranny mount, suspension, etc.

phrosty

Air filter... that seems to be the answer to any problem on these things. But no, it's not the air filter. I've never had a car that made a popping under the floor board you could both hear and feel due to a dirty air filter. But, I digress...

No, nothing's stuck either - I did check that.

As far as I can tell, the only thing in that area under the car would be the propeller shaft. *shrug* The retaining band looks like it's got a lot of slack in it. I've never looked at it and am unsure if this is typical, or atypical and probably the culprit. Either way, I'm glad I found a PDF copy of the FSM for this thing... although, it would appear there's not a lot I can do without proprietary diagnostic equipment. Which is one of the biggest reasons I still keep an '85 300CD under the garage.

It really does feel almost like a rock is hitting right underneath the floorboard under my feet. It doesn't happen all the time, usually just when giving it gas and letting off within a few seconds. It's not always the same "strength" pop in noise or feel, and it doesn't matter if I'm taking off from a dead stop or giving it a little gas to pass someone. I haven't noticed it happening in reverse, only drive and S.

XLR8R

Possibly just a loose component swinging slightly. If something is striking the chassis repeatedly, there should be a sign of it: gouged undercoat, bright metal, etc.

^ This. Possibly engine/trans mounts. When you rev and abruptly release, the engine block torques counterclockwise and then clockwise (when viewed from the right). If you can make the noise by revving in neutral, vs driving, you can isolate it to the drivetrain. The dogbone mount is just to the right of the oil filter and absorbs the engine torque action -- stretches during rev and compresses off rev. It could be cracked/loose. Try looking/listening under the hood, while someone revs it.

If it only makes the noise when driving, then suspension is more likely. Lots of possibilities there, but sharp braking should do it also, along with abrupt off-throttle.

XLR8R

Here's an undercar video. There is not much equipment directly under the driver pedals:

phrosty

Will try and report back.
I didn't see much in that area, save for what appears to be the propeller shaft. And, again, there's a support band that's not flush against it. May be that it's not supposed to be flush - I suppose a photo would help, and I'll try to take one this week and post. Thanks for the helpful suggestions, though - ver'much.

phrosty

Never mind. It's the prop shaft safety loop. It's not supposed to be flush.
Meh.

phrosty

Sorry for the delay - tried suggested methods of checking, with nothing of worth mentioning. The problem has actually resolved itself, with no noticeable issues afterwards so... Gremlins. *nod*