I'm really stumped. I get this weird whopping noise from engine which is relatively quite at idle but still noticeable. And horibbley loud when driving between 2 and 4500 rpm I have no idea what it is. It is Kind of subtle . But you hear it when listening for it. It almost sounds like a slight misfire. I've recently changed spark plugs and checked each coilpack none seem to be bad as the engine bogs when I pull each one. I'm thinking maybe injectors but I'm honestly not sure. I've checked the exhaust with the dollar bill trick and it seems to blow exhaust out steadily so I don't think it's a burnt valve. And it's a little bit of a different tone than noisy lifters.( less of a tapping sound. More of a wop wop sound) . Any ideas ?

 

does it only make the noise while moving, or does it make it when you are in neutral and raise the RPMs? If it only happens while moving then it shouldn't be engine related.

 

At idle as well and while revving in neutral

 

Does not seem like injectors would do that.

So you have confirmed that spark is ok.

Does the engine block move around much if the car is in first gear if auto, or the clutch is barely engaged if it' s a 5 speed. This test checks condition of the engine mounts.

 

Misfire should be easy to identify, especially with the power loss. If there is no misfire, i would imagine maybe mounts or could it be a pulley/belt issue?

 

my motor mounts are definitely bad. but it feels like a loss of power slightly because the car is still pretty quick but the sound seems to occur in the same cycle as the engine. this is why i checked for burnt valve because at first it sounded like a valve that wouldnt seat properly like a hollow sound almost as if air was getting past somewhere or through somewhere. but not quite the average vacuum leak hiss. like this holllowish tap sound. could it be a burnt sparkplug. i checked coilpacks they seem to fire properly. and i recently changed spark plugs to ngk laser iridiums which i did not check gap on

 

If you could upload a vid of the sound maybe someone could pinpoint it for you. Should be pretty easy to take since it happens when the car isn't moving.

 

Seems like you need to replace engine mounts.
That needs to be done anyway, and it might solve your problem.

an engine mount would act up the most as the engine is under stress. Like acceleration.

 

I have a video where the sound is clear. How do you post videos. I only see the link for photos

 

 

[youtube]https://youtu.be/vWF0UHadP50[youtube]

 

 

Not helpful.

Please take a video while you are under the hood.

use the throttle cable to rev the engine.

move the camera or phone around to various places near the engine where the pully s are, and near the transmission.

also a ten second video is not long enough.

Picture yourself watching some one else' s video.
Which clues might an experienced person get from that video. .

 

I think the op is referring to the sound at about the 7 second mark. I don't know what it is, but I have heard other engines make a similar sound and that was due to valve timing, engine load and other factors.

Maybe the muffler has become a bit less muffling than it used to be and allows the sound to be heard.

 

I'm open header. But as long as it isn't anything serious it's an old engine so slight change in how the car sounds is expected. I just wanted to make sure. Engine is coming out soon anyway

 

Do you have stock or aftermarket headers?

If you are running stock headers, many of us here run Warpspeed Y-pipes.

 

Yeah I heard something @ the 5 sec mark that sounded like you foot slipped off the throttle and you got back on it to accelerate....

 

yeah it did but not that more so That sort of hollow tapping noise you hear when I hold the revs

 

And I have obx-r header and y pipe