Got this annoying long-term problem with my car, the one I use for business travel: some knocking noise when accelerating out of a corner, any gear, most any speed, either direction of turn. Had it to six different shops, and a couple issues have been found, though not directly related to the problem so the problem persists after a good off-and-on 9 months or so. Replaced the front axle shafts twice - no change. Replaced the rear axle, which had worn u-joints, so that did eliminate a different noise. One shop says the shafts are bad - both of them, with only a couple thousand miles on them? Another suspected the wheel bearings, which sounded reasonable at ~147,000 miles, but further investigation shows they're fine.

The dealer says they can't find the cause but that "it's not safety-related". Uh, really? So when the problem goes full-on when driving down the middle lane on I-90 in Chicago at 3:30 Friday afternoon, that's not a safety problem? Because, sure as shit, someone would shoot me if my car crapped out right then and there.

I've taken it to a brand-specific dealer, an axle / alignment specialist, and a transmission specialist, plus a few general automotive shops. Nothing definitive. I don't care about the cost for the fix; I just want to know what is the problem so I can make a decision from there. But now I'm hemming and hawing over finding yet ANOTHER shop to look at it.

I think I'll give it one last shot (lucky 7?) and then replace it with something else. Barely driven the car the last 9 months, using instead one of my wife's cars for biz travel. Frustrating since otherwise the thing is fine - still gets good mileage, motor runs fine, good size for my needs. Comfy enough for my long trips, never stranded me. I'd like to keep it going but this problem is stumping everyone so far and I don't want an axle / transmission failure to put me in a bad spot.

Have you considered something like this:
http://www.amazon.com/STEELMAN-97202-Wireless-ChassisEAR-Diagnostic/dp/B00123J79O

I have never used one myself, and cannot vouch for them. But in the past, I've certainly used other listening devices (stethoscope, screwdriver) for locating noises on an unmoving car. This set seems like it might do the same for a moving car.

Perhaps you could borrow a set.

edit:
I included the link as an example product. I haven't done any research into which competing product is best.

Not likely, because I'm not going to fix it myself. The latest guess is that it's the transmission, at the point where it interfaces with the drive shafts - and there's no way I'm going to tear into a transmission.

But I should show that to my brother: he'll spend 2 hours listening to a problem, 6 hours online searching fora and youtube for probable causes and suggested fixes, another 2 hours looking online for the parts from the cheapest place, wait a couple weeks for all of the parts to arrive, and 4-20 weekend hours working on the problem. For something that may take a shop a couple hours and $400 to deal with. He'd be all over a tool like that! haha.

I'm actually thinking about something similar for the machine work that I do. It would be handy to monitor and record audio and video of axis movements in areas where I can't directly monitor them for safety reasons. Maybe a GoPro?

But hell, maybe I'll pick up that thing anyway. Thanks for the idea.

Edit: Annnnnnd bought. Damn you. ; ) At least maybe it will let me help the tech pinpoint it with a drive along. They were having trouble even hearing the noise, and I kept telling them to hammer on the car. I couldn't convince any of them to beat on it, and the last shop said it took three guys to finally hear anything. Hell, the way I drive it (I like to corner hard) I can hear it when pulling out of the alley.

Sounds rough, hope you got through the day without too much trouble. I've actually considered composing a WRAP for myself in the past, and got as far as making a rough draft, but never had the chance to put it into action. Here's hoping you'll find it beneficial.

Personally, I'm doing alright today. Minor annoyances aside, nothing really worth bitching about. So I'm relying on you guys for my daily dose of complaints and grievances. :-)

Thank you. I did manage to update my WRAP today, next week will be the final meeting of the WRAP-course I'm following. I also did some walking outside, when I needed to visit the chemist for my medication, I took a roundabout tour back.

http://www.carsdirect.com/car-repair/3-causes-of-engine-knock

Thanks. It's not engine knock, though. Doesn't do it on straight-line acceleration - or at least it's very light in comparison to turning - and it otherwise runs as smooth and strong as it ever did. And it doesn't sound like engine knock, which is very distinct.

What it does sound like is that the rubber boot over a CV joint went bad, or is loose; it's almost like taking that boot off and hitting it against your palm - sort of a hollow knock (engine knock is more of a metallic clatter). But all of that crap is new, with maybe 1,000 miles on it.

In the meantime, looking for replacement vehicles. Found a couple but they take two completely different directions. The common sense side goes one way, essentially buying a slightly newer (but still used) version of the vehicle that I've been borrowing from my wife. The other direction is a sporty but economical new car that she will drive, and I'll simply take over from her - permanently - the one I've been borrowing. Cost is very close between the two, but after selling the motorcycles I wouldn't mind getting the small car. Fortunately, both are available with a stick shift.

I know you're typically knee-deep in machinery, but somehow, I didn't imagine you doing the repairs yourself. Probably because you mentioned going to several shops looking for an answer. But I thought you might be fed up enough to chase down the location, so you could usefully direct an otherwise lost mechanic.

If it turns out to be a magic device, please let me know. I just sold my 17 year old car last month, so hopefully, I won't be chasing occasional noises anymore. Still, I'm interested.

Best of luck!

As for the GoPro, sounds good if even only to safely satisfy curiosity. Once in a while, I read an article about some unfortunate farmer who hung off the front of a slowly advancing tractor, [presumably] trying to diagnose a problem. Yikes. I don't know anything about the wireless live feed capabilities of the GoPro, though. I assume it does.

I do usually pawn off the repairs, but I also try to be a good customer who can provide a useful set of clues for the technician. You know, because that's what I want to get from my own customers - so this should help with that.

And it'll be a fun toy to play with, though I suspect it will spend most of its life at my brother's house.

Talked it over with the wife and I think we're going to try to fix this thing, even if it takes a bit longer. For one, even a transmission replacement is cheaper than car payments. And I like the car even though it's nothing special.

Went to the dentist to have a broken filling replaced. Ended up with a root canal. Yay!

This should make you feel better. I had three root canals last months and I had to drive 300 miles to get each one done.

Now, that really sucks. I wouldn't wish a root canal on my worst enemy.

-Google weird car noises

try this link to get more ideas-
http://www.autobytel.com/car-ownership/maintenance-repair/identifying-weird-car-noises-105716/

edit- hope you find the solution

Thanks - I hope so, too. It certainly can be fixed; the car didn't start its life this way, so something has changed. Just a matter of figuring out what is different from before.

Yeah I honestly want to know what it is and hope you keep us informed. 145k miles is nothing and for it to make a noise is just plain weird. Anyway you can record audio of it?