doktaluv

My '84 T/A just recently started doing this and has me totally stumped. For the past two days there's been an occasional weird rattling sound when I start up the car. It's "occasional" at best, happens once every ten starts or so. When revving the engine, it revs perfectly fine, but when the RPMS start heading back down to idle, the "chunky" rattling sound starts. Sometimes it does it, sometimes it doesn't. It's one of those fun sounds that is only occasional enough to be incapable of diagnosis. When revving, it's fine, but upon deceleration, you can hear it.

Of course, now that's gone away to the point I can't figure it out, but now I'm getting a low-to-medium whining sound from my front end. It's on the passenger side and sounds like a tire's rubbing against the wheel well -- but it's not -- but once again, when revving up and accelerating rapidly, no problems, but upon coasting or taking my foot off the accelerator, it starts up. It sounds pretty solid at first (around 35mph) but then becomes intermittent between 0-10mph. When the car is in my driveway and I rev, no sound whatsoever...only in motion does it occur.

So what possibly could these two sounds be? I'm leaning toward the exhaust for the "chunky" occasional sound, but the "whine" has me completely stumped.

doktaluv

It appears it's only doing it in third gear.....first no problems, second is silent like no tomorrow....as soon as it hits third, however, it starts up.

Transmissions. Oh joy.

gibsongod716

95% for the exhaust, yes, it is most likely a hole or gap, when I take my foot off the gas I get a burble grungy sound because my headers are not fully connected to the y pipe...

for the whine, when you let off the gas, is it mostly like a chirpy whine(every few seconds), or is it like a constant supercharger type whine

if its chirpy i would say its most likely a belt.... when i rev mine it sounds like a quick whistle and when i drive and the car shifts down when i left off it whistles and whirls down to idle...

for a supercharger whine i want to say any kind of broken gearing, perhaps in the tranny or bad flexplate?

this is coming from my personal experience, it may not neccessarily be your problem...