netabuse

So there's a new noise under the hood now. While driving, there's a banging/knocking (more a klunk than a knock) from forward of the firewall that I can feel through the pedals. It comes on above 2k and is there all the way up to 4k or so, when it blends in with background noise, though even at high speed I can still <i>feel</i> it.

Rolling down the window, I hear only the usual engine noise; and when I stop and put it in neutral and run it up to 4k or so I don't feel it, and everything sounds normal.

Now, I did have the new downpipe put on, and I went with "aftermarket" to save $200. Unhelpfully, the receipt only shows the part # for the cat. I'm hoping it's just that what I'm feeling is the pipe banging, and I can get that dealt with either at the pipe or engine mounts.

What freaks me out is that the last time I heard banging at this frequency, it was the sound of one cylinder in an old Hyundai deciding it was on its last leg before giving up and seizing. Of course, that only took about five minutes, but that five minutes is burned into my memory.

Not that I worry too much about that: all the logs say the engine is running just fine except for cylinder #4's tendency to intermittently pull timing from 1.5 to 6.8 degrees. And if it were as bad as it sounds, it wouldn't be "intermittent".

So I'll take it in and spend more delicious money. Or I'll give up and trade it in for a CPO 350Z and cut my losses. I mean, $9k and I get a 2-year drivetrain warranty? Hmmmmm....

fredfromny

Any smoke or oil consumption?

netabuse

Re: 70k, and god wouldn't that be fantastic