HTY67

I have a 96 Civic with 192k miles.

The engine makes an intermittent, random popping noise until it's warmed up. The noise increases in frequency and amplitude as throttle and rpm increase. Once warm, the noise goes away completely. I can prevent it when cold by going really easy (accelerating at 10" hg vacuum or higher), or by warming it up until it idles down to about 1000 rpm before starting out.

It started about 5yrs ago but only on cold winter mornings. Now it happens even on summer mornings.

It used to only happen under load in higher gears, now I can even get it to do it by pulsing the throttle under the hood by hand which finally helped me figure out a little more about the problem. I'll get one or two pops out of it that way before it gets too warm and it goes away. I'll say it sounds like it's coming from the intake side of the #4 cylinder / distributor area. I don't hear or feel anything from the injector.

Over the years I've replaced the exhaust manifold, tuned it up (wires, plugs, cap, rotor, timing check), adjusted the valve clearance and none of those had any effect.

Average oil change interval over last 120k miles is 3100 miles. PCV valve is new. Air filter good. No check engine light. NOT CV related (happens when stationary and not a rhythmic noise like a clicking CV).

Any ideas?

green-

you got orville redenbachers on your manifold

redeg666

hahahahaha

nothing_shocking

Try to pinpoint where the noise is coming from. Use a long screwdriver with a plastic handle, put it on different spots on the motor until you find the place it's loudest. Or, along with doing that (or if you don't want to do that) try to post a video of it. That always seems to help diagnose stuff.

HTY67

I said where it's coming from. Right, rear corner of the head. Intake side of cylinder 4.

Any help?

nothing_shocking

Oh, didn't see that. Is it a vtec motor or no?

In all honesty, if it's been doing it for over 5 years now and it still runs fine, I really wouldn't worry about it... With that many miles, depending on what it is, it might be cheaper to just get a new motor (assuming it's a D series, those are cheap and easy to find.) I know that's not what you're here to find, but it's always an option.

HTY67

yeah, its a vtec, D16Y8, EX.

I'm not toooo worried about it because I can avoid it by warming the engine up very gingerly, (f--- the clowns behind me for the first 2miles), but I do plan on having the car for at least another 100k miles so I'll have to fix it at some point, probably, so if I can figure it out I might as well do it now. Problem is I can't keep swapping parts.

nothing_shocking

Well, if you plan on keeping that motor for that much longer, I HIGHLY suggest you get a new oil pump ASAP. You're getting into the range where that pump starts going out. That's what happened to my friends Y8. Oil pump failed and his motor seized up. He got lucky and found another one with only 15k on it, lol.

HTY67

Good suggestion. Maybe next time I change the timing belt I'll add the oil pump to the list.

Back to the original question. Anyone heard of a popping noise occurring only on a cold engine from what seems like the intake side of the head? Anything I might look at?

MeGotRoundEye

Sounds pretty weird to me. Have you ever had the motor out of the car? Does the popping sound like it could be a bracket or motor mount or something metal hitting something in the engine bay? Could it be spark knock? Exhaust leak? Maybe you didn't replace the gasket when you replaced the manifold... I think you should post a video. It would help.

enders1218

Hi my 96 honda civic with 210k miles just started making a popping sound that sounds just like popcorn from right behind the engine im affraid to run it to pinpoint the sound incase i further damage it. It started on the way to the grocery store so i went home to take a look at it since i wasn't very far. I got home parked opened the hood and looked engine temp was norm, oil changed every 3000-3500 miles, around 3500 on the current oil, shortly after i heard a dripping noise and i noticed my coolant was being poored rapidly. There was no trail up my driveway so it started after I parked. Are these 2 related? could it just be my waterpump went out and if i fix it the noise will go away or are they 2 separate incidents? i wanted to keep this car for another 50-100k miles but i dont wanna put too much money in it and i dont wanna replace anything to find out the noise is bigger problem

Natural Aspirations

What is with the new trial user accounts?

MegasXLR

Waterpump won't fix the problem. I just got water pump, belts, seals, motor mounts, and valve adjustment done. After I got that done then the noise started to come about for me. It's been about 2 weeks... help pl0x...

BobbyRodriguez

Its blown