I'm driving a 95 automatic DC4, and can't figure out for the life of me what this sound is.

Only seems to happen when the car is rolling, occasionally when I completely let off the gas there will be a kind of gurgling/buzzing sound for about a second followed by a monotone whine lasting between 3 - 10 seconds and finally stopping with the same gurgle/buzz that it started with. The whine doesn't change in pitch with either wheel speed, or engine speed. It also sounds hydraulic or air related, not so much mechanical, I could be wrong of course. Braking doesn't affect it, but opening up the throttle stops it.

From inside the cabin it sounds like it's coming from the left side of the engine bay but it's hard to tell. I tried to replicate the noise with the car in neutral and holding the throttle at a moderate RPM but it only makes the noise while moving. At first I thought it was only the power steering pump because I had a bad leak and every time it was low on fluid it would make a similar noise without the whine. So I ripped out power steering, drained and looped the rack. But of course it came back. Any ideas? Hoping it's not the torque converter but it seems to be leaning that way. I've been trying to source parts for a standard swap anyway...

 

I'm actually thinking it's the distributor now, I didn't give it another thought because I thought a bad distributor sound would fluctuate with the RPMs. Sound likely??

 

pcv valve ?

I would love to hear it. Can you put a video up ?

 

Camera on my phone doesn't work at the moment, or I would. PCV is getting replaced soon either way, car has 245000 miles and last owner didn't know of any maintenance besides oil changes. Would the PCV valve potentially make a loud whine if it was clogged or stuck shut? I picked up a new distributor, cap and rotor today so that's going on today.

 

It's really the only thing I can think of that would do that, save for the air filter. The pcv valve has a valve that can stick open or perhaps just stick open enough to make a whistling noise.

 

check your coolant level.
if its low and theres a air pocket, when you accelerate the coolant rushes in to your heater core causing a gurgle type noise. my girls camry was doing that.

luck

 

Might be some kind of vaccume related thing if it only happens at closed throttle. At closed throttle the manifold is at max vaccume. At WOT there is no manifold vaccume so just a thought.

 

Well the noise was definitely the distributor, I replaced it and timed it about a week ago and there is no hint of the noise. I am thinking I have a vacuum related issue and possibly air in the coolant. I've bled the cooling system a few times and still get an occasional bouncing idle at warm up, though it has improved drastically after bleeding. Also now while sitting at idle the engine will stutter and shake for a split second like it's not firing. Only happens every now and then which makes me think it's not the timing, which I've tripled checked. No engine light yet. I'm thinking it's either not getting enough fuel at times or some kind of vacuum leak.

Next project was going to be cleaning out the intake manifold/throttle body and replacing the PCV valve as well as fuel filter and all new coolant. But I may save my money to try and find a clean DC2 instead since this car has irreparable body damage.

 

iacv

 

That was going to get cleaned to, as well as FITV.