Odd noise with engine; 95 del sol, maybe VTEC, maybe not

[ttown]

Recently bought a 1995 del sol for my kid as a first car. Things seemed fine for a while.

She says one day the car died while driving it and it coasted to a stop. The car started fine right after, but made some noise. She says the car seemed to "trip up" when starting to move from a stop; and had some loud noise coming from the engine.

So i go to check it out.
I think there are 2 different noises.
1) a sound similar to what you'd expect from unscrewing a lid on a tin can. It is intermittent, but seems to only happen when the car is in motion, or when the car is being turned off. My uneducated opinion is that it sounds something between a "creaking" sound and something electrical. The sound is the same whether going 2mph or 20mph.

2) a constant "metalic" sound coming from something near the air intake. It sounds related to the speed of the engine. Revving the engine makes it sound 'faster'. It may be "normal" -- but i don't remember it being there when we bought the car. I'm 95% sure it wasn't.

I tried searching for the source of the noise and i can't tell.
It is definately coming from the left side (when standing in front of the car, looking into the engine compartment).
My initial thought was Alternator, but all the pullys/belts i could see are on the other side of the engine (to the right, when looking into it from the front). It was dark and i had poor lighting, so i may have missed something.

Other than the sound #2, the engine seems to run and rev smooth; no sputtering or anything like that.

When she turns the car off, the sound #1 returns for about 1 second and occurs AFTER the engine has quit firing, along with a sound that sounds vacuum or pressure related, maybe.

There were no unusual smells that i could detect.

When i went with her to observe sound #1 while driving, she said it sounded louder and more frequent before and is quieter and more intermittent now.

The car is a rebuild -- so i'm not sure which engine it has. The previous owner said VTEC, but he may have been bs'ing. It looks like it has many fancy additions to it (from generic boring cars that i've owned), most noticably the air intake.

Recent work: basic transmission service and oil change

Any ideas?

tia
ttown

 

[Arkaign]

It's a 95? Check the motor mounts, sometimes they can make a creaky noise, although of course it could be a lot of other things, even tensioners can make weird noises.

The metallic noise is a bit scarier. As it's matched to motor speed it could be something in the upper end of the motor, rod/valve/cam/etc. OHC motors are a little noisy anyway, which is normal, but if it's really noticable from inside the car, it may be a problem developing.

Others will chime in as well, I'm more of a tinkerer than a pro in this area.

 

[TakeNoPrisoners]

The metallic sound might mean permanent engine damage. Post a recording of the sound.

Where does the sound come from? The top of the engine or lower?

 

[NutBucket]

A common failure of that era is the bearing in the distributor.

An easy way to listen for noises is to take a long screwdriver, place the tip on various parts of the engine and put your ear to the end of the handle. Voila, you have a pseudo stethoscope and hopefully you can isolate the source of the noise more easily.

 

[ttown]

OK -- i've asked her to get a recording and will update when she's able.

I doubt it's motor mounts -- mostly because it sounds partly electrical and not in that location. (But not certain)

I'll hope it's a bearing in the distributor as that sounds the easiest and cheapest fix -- and sounds very plausible.
IIRC, the distributor was in the general location.

That coincides with the car initially dying, right? According to her, she was basically coasting when it died. She wasn't stressing the engine at all.

If that's not it -- the noise sounded like it was near the top end -- on the left (facing the engine)
Will try to narrow it down late on monday.

 

[NutBucket]

If it's the distributor the easiest fix it to buy a new one. Probably will run you in the neighborhood of $200 or so.

Not sure if it coincides the car dying...unless the cap is cracked or there's a loose wire. Typically there are no intermittents with ignition components; they either work or don't.

 

[Hellotalkie]

Not that this adds anything to the thread but.....I love my del sol!

 

[m0r1san]

I used to have a 95 del Sol Si. Great car to learn how to drive and work on!

I would second the distributor bearing theory.

When she turns the car off, the sound #1 returns for about 1 second and occurs AFTER the engine has quit firing, along with a sound that sounds vacuum or pressure related, maybe.

This happens because the distributor still spins for a moment after you turn off the engine because it is connected and in time with the engine's camshaft, which continues to rotate until it winds down to a rest. Probably should get this checked out. Not sure why the car would just die from a noisy bearing (unless it intermittently seized), but I'd also check your ignition wires and spark plugs while you are at it.

The vacuum sound is probably just coming from the intake. It will be even more pronounced if there is an aftermarket intake. My car makes a loud sucking sound when I turn my car off.. I would suspect this sound you are hearing is nothing to worry about.

"Metallic sound" is too vague That could be totally normal sound from the intake, injectors, motor mount, etc. A sound clip would be helpful.

Good luck and cool car!!!

 

[JeffreyLebowski]

I used to have a 95 del Sol Si. Great car to learn how to drive and work on!

I would second the distributor bearing theory.



This happens because the distributor still spins for a moment after you turn off the engine because it is connected and in time with the engine's camshaft, which continues to rotate until it winds down to a rest. Probably should get this checked out. Not sure why the car would just die from a noisy bearing (unless it intermittently seized), but I'd also check your ignition wires and spark plugs while you are at it.

The vacuum sound is probably just coming from the intake. It will be even more pronounced if there is an aftermarket intake. My car makes a loud sucking sound when I turn my car off.. I would suspect this sound you are hearing is nothing to worry about.

"Metallic sound" is too vague That could be totally normal sound from the intake, injectors, motor mount, etc. A sound clip would be helpful.

Good luck and cool car!!!

I'm lost, so the Honda cam keeps spinning down when the motor is turned off? I though the cam was connected to the crank via chain or belt. When you turn the engine off, the crank should stop spinning, thus the cam(s) stop spinning. I have waay more experience with pushrod motors, so not sure with OHC setups. Just wanting clarrification for my part. Or is there a clutch for the Cam Shaft?

If it makes the sound in time with engine speed, I would assume it has to do with the drive train.

 

[m0r1san]

I'm lost, so the Honda cam keeps spinning down when the motor is turned off? I though the cam was connected to the crank via chain or belt. When you turn the engine off, the crank should stop spinning, thus the cam(s) stop spinning. I have waay more experience with pushrod motors, so not sure with OHC setups. Just wanting clarrification for my part. Or is there a clutch for the Cam Shaft?

Sorry for the confusion - what I tried to say is that the distributor spinning is a function of the engine (camshaft/crank) spinning. There is no delay in the camshaft

When the key is turned ON->OFF, there is a short, ~1 second, period of time where the engine is winding down to a halt. This "winding down" duration could be extended if, say, you turn the engine off at 6,000rpm, then it could take a few seconds to go to 0rpm, depending on how heavy the flywheel is, etc. Might not be a bad sanity test, actually.

 

[m0r1san]

That said, if we suspect this to be a distributor bearing noise (noise #1), and it's a function of the engine revs, this noise should become faster with more revs.

ttwon, is this the case?

 

[RocksteadyDotNet]

I never got the point of the second gen CR-X.

Why have a FWD two seater?!

 

[NutBucket]

Because its more efficient and was cheaper for Honda to build. Just because its FWD doesn't mean it can't handle well.

 

[RocksteadyDotNet]

Because its more efficient and was cheaper for Honda to build. Just because its FWD doesn't mean it can't handle well.

Actually, it does.

FWD = Fail wheel drive.

 

[NutBucket]

ok......

 

[Hellotalkie]

Actually, it does.

FWD = Fail wheel drive.

I didn't care whether it was RWD or FWD, it has tiny engine with substantial weight to pull. Besides that, the roof comes off and the back window comes down. Find me a car with similar mileage ~(30/40), reliability of a Honda and has those features.

 

[LTC8K6]

The Mini seems to handle okay.

You may disagree with the way front wheel drive handles in general, I suppose, but it doesn't automatically handle badly.

I think it's mostly a case of preferring the way rear wheel drive handles, rather than front wheel drive being bad.

Either type can handle poorly, and either type can handle well.

 

[ttown]

I finally got to revisit this a couple days ago.

The high-pitched sound is the air intake. I threw a towel around it and the noise went away. I guess it's normal and i just didn't notice it when i took it for a test drive before purchase.

I think that puts the motor mount possibility back on the table as an issue -- as for the 'creaking' sound.

However: While we were standing around looking at the engine running trying to find the high-pitched sound, the car died one time. The car was cold and there was no sputtering or mis-firing so I'm leaning toward that was just because it was cold.
That's what i'm hoping, anyway.

Everything is in the way of me seeing if it's the motor mount -- so i'll have her take it somewhere for them to look at it. Will update when i know more.

Thank you to everyone for your help so far
ttown

 

[ttown]

update:

The car quickly progressed to dying more and more frequently until it finally wouldn't start.

The failed part turned out to be the distributor. A shop replaced the part and the car runs fine.
Unfortunately couldn't easily find a "pull-a-part" yard with one, so it turned out to be a relatively pricey fix -- but it's done.

Thanks to everyone that gave their input
ttown