Jim in St.Louis

I just put headers on my Cayman to go with my aftermarket exhaust system and now can hear a little valve noise. It only happens at low RPM (1000 - 2000) and then goes away, but at just over idle I can hear it. The car runs well, but I wondered if the lack of cats, allow this additional sound or do I have a serious problem?

Byprodriver

Jim, I am guessing that this noise goes away when the engine warms up. If this is the case you are probably hearing the lifters which have leaked some oil while the engine is off causing the noise until the lifters get pumped up with oil and reach operating temp. Removing the cats causes a extended warmup period & you probably have been listening more closley to your new exhaust. Changing the oil should help especially if you use Mobil 1 &/or 0W- weight oil.

Jim in St.Louis

I did just change the oil to one of the botique style $11 a quart stuff, but I think that I still hear the noise after the car is warmed up. Also at low RPM.

extanker

you are not clear. when did the noise start ? after the oil change ? after the exhaust work ? whatelse was done ? make sure you dont have an exhaust leak they can mimic a valve tap noise, imho

Jim in St.Louis

I first heard it after adding the headers and I changed the oil while the car was up in the air on the rack.
We inspected it for leaks, while it was up and found no leaks. Nothing else was done to the car.
Again I only hear it between 1000-2000 RPM.

extanker

what year? mileage?IMS noise?maybe a po techs ear on it could help

Jim in St.Louis

2007 base Cayman, 42,000 miles, I hope it isn't IMS, but I have not heard of any noises people have talked about from IMS failure. A friend had IMS failure and he said there was zero sign of a problem until the engine went. Just the loud sound of chunks of metal in his engine, as the engine was failing.

extanker

get a tech ear on it and start cutting open your oil filters

Macster

There is such a thing as coincidence and you want to be careful how you proceed but if the "valve" noise appeared concurrently with the header/aftermarket exhaust system change over I'm thinking you have an exhaust leak with another possibility the exhaust system has a hanger or something loose and is rattling.

Either one can mimic the sound of a valve noise.

Best I can offer is get under the car and with a stethoscope pinpoint where the noise is coming from. If from inside the engine, under one of the camshaft covers, well, then you know it is internal.

But if you eliminate the noise as coming from inside the engine then you know it is not internal and you can deal with it.

If at any time the noise gets worse or the engine begins to manifest untoward behavior shut off the engine first and ask questions later. Do not start the engine again. If it needs any starting let a trusted/experienced Porsche mechanic advise you.

Jim in St.Louis

I changed the oil a week ago and dug the filter out of the trash, opened it up and there was not a spec of metal in the oil filter. I will attempt to listen to it as suggested.

extanker

THAT IS GOOD also check for bits of colored seals. iirc green for cam seals ,orange for ims bearing seals. ironic that you can hear more engine noise with headers. still get an experts ear on it just to be safe. for what it is worth i think the motor is okay with just some normal noise you did not hear before .imho. keep us advised please

Jim in St.Louis

Thanks for everyone's input, I will respond when I find out something.

gmsracing

I've noticed more liftr noise after doing exhaust too. I think either i have a small leak that amplifies the noise or the exhaust itself amplifies it.

Jim in St.Louis

I checked on other forums and found that lifter noise is not unusual after installing headers. Apparently the thinner header walls or just the open exhaust lets you hear the noise. Although I will check a couple of friends who do engine mods to other cars.