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[Osiris]

It seems like my valves or noisier than they should be. I can distinctly hear them "click" open and close. The car runs good, so maybe i just don't have experience to really know, but does this sound like a normal thing for an '87 2.5L N/A?
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'87 924S 50K miles black/black

[edredas]

It's normal to hear a light tapping noise from the top of the engine. It shouldn't be too loud, or louder on one cylinder than another. If it is, check that your distributor cap is secured properly.
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'84 944 -White, Brown interior
'84 944 -Red, Automatic
'86 944 -Garnet, Fully loaded, Koni suspension
'87 924S -Red, 300hp 951 swap
'87 924S -Red, Project Car
'88 924S -Red, Daily Driver

[masterdave]

at higher rpm's you will defiantly hear it on any car. most of the time the muffler will suppress most of the sound on most newer cars, but its still metal hitting metal quite fast, it will make a distinctive clicking. How ever if you are nervous check your piston compression, if the sound is caused by a bent valve then you will also be losing compression, its a simple check, with a cheap tool, and it will tell you if all your valves are fine.

[Osiris]

At idle with the hood open the sound is distinctive, but it doesn't sound unhealthy, just loud. Any oil additives to increase the effectiveness of engine oil on the valves?
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Keep a Chevy motor in a Chevy
Keep a Porsche motor in a Porsche
Keep a Ford motor in the dumpster

'87 924S 50K miles black/black

[gohim]

A few questions for you...

How long (miles?) have you owned this car, and have you always heard this noise? If the car has been run without regular oil changes, the lifter oil passages can get clogged, resulting in lifters that do not pump all the way up. If this is the case, sometimes the lifters will clear themselves if you do regular oil changes with a quality oil over a long period of time. If this does not fix the problem, then new lifters are the only cure.

What weight and type of oil are you running, and are you/have you always done the oil changes on schedule? Many people are running a very high light weight oil as suggested by new car manufacturers, this can cause older cars that original used heavier weight oil to make noise (not good for the engine). I run Valvoline 20W-50 most of the year, but I'm in CA. If your where it snows 10W-40 would be better for you. Synthetic oils are also thinner and will cause oil leaks and noises that you won't get while running conventional oil.

Can you/do you tell/know the difference between lifter noise, and fuel injector operation sound? The fuel injectors are electrically fired, and they are loud. When the engine is running, they make a clicking noise that many people mistake as lifter noise. The Porsche 2.5L engine has hydraulic lifters. On a good running 2.5L engine, you should not hear much of any lifter noise. Real lifter noise on a 2.5L engine signals that something is not right, as one or more lifters are not pumping up properly.

So first make sure that what you are hearing is really lifter noise. If it is, then you need to take a look at the oil you're running and the oil pressure.

[ic932]

I agree with gohim, what you are probably hearing is the injectors firing. Rather like a sowing machine?

If your motor has been asleep for a while, noisy tappets are common and even if expected tend to give one the shits lol. Once pressure/heat has been established, I find the ticking sound of the injectors a relief!

[Osiris]

I've owned the car since '05 and have put probably 20-25,000 miles on it; have always changed the oil and filter within at least 5000 miles. I used synthetic oil for the first few years and eventually picked up on the oil leaks it caused. I switched to dino oil and that has helped. I use 20W-50 in the summer time and switch to 10W-40 in the winter.

Gohim...yeah, i don't really have that much experience with car repair outside of cars that i have owned, just always fixed the ones i had by myself. So, it very well could be the injectors as i have no real frame of reference.

It has been sitting for about 3 months, i changed the oil right before i parked it, so hopefully it gets better as the oil really moves through the engine in the next week or so. The oil pressure has always been good. The car only has 70,000 +/- 3000 original miles on it at most, not sure exactly as the odometer has been broken for different stretches of time throughout my ownership. So, the engine is in good shape, never really had any trouble with it and did the front engine service sometime in '06.
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Keep a Chevy motor in a Chevy
Keep a Porsche motor in a Porsche
Keep a Ford motor in the dumpster

'87 924S 50K miles black/black

[bcblase]

The noticable clickety-clickety-clickety noise from the engine bay when the hood is up has always bothered me.

I thought it was valves also, but eventually realized it was the noisy injectors doing their magic...

A little stomp on the accelerator, and it all goes away.
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1987 Porsche 924S - track toy
1986 Mercedes 190E 2.3-16v - autocross
2007 F-150 5.4L Lariat Supercrew - tow beast
1994 Volvo 850 Race Wagon - 24 Hours of Lemons Car
2001 BMW 325xi - daily driver