rnl, can you tell us what options you have? SC, PSE?

 

No performance options

Agate gray
PDK
PSE
full leather interior black gray
Heated steering wheel
Retractable mirrors
20 inch wheels
Tracking headlights
Vented and heated seats
Front and rear sensors for parking
Built in radar detectors and "laser" jammer
Keyless entry


Sure there were software updates and an occasional rattle that was fixed.

My only complaint is that the temp gauge shows 194 ALL THE TIME when operating. And that can't be correct

 

Why would you think that it "can't be correct"? I am assuming that when you start your car from cold that it is not indicating 194. My car reads 194 at virtually all driving conditions, including track. Oil temp on the other hand varies from the high 190's to low 220's, except on the track where it is usually pegged at 250.

Frank C.

 

What convinced me that the 194 is essentially a digital "idiot light" were readings taken off the OBDI port. Think about it, do you believe that any engine is capable of maintaining a constant engine temperature? By design, when coolant temperature rises above the set point the thermostat opens allowing coolant to flow at higher rates through the radiators allowing it to be cooled.

Porsche probably fixed the temperature reading at 194 to stop the questions...like, why is my temp at 219F?

 

There might be some truth to this as, before the last PCM campaign, my temp read mostly at 200, but varied a bit. Since the campaign, I don't think I have ever seen it move past 194.

 

I guess I have been conditioned to take a digital readout as correct, but your logic is hard to challenge. I think you are on to something here.

 

Ok guys, I *may* be making some progress here. Perhaps some of you could try to reproduce the little experiment I ran today. First, here's my logic about the vibration:

• Doesn't occur in Neutral = rules out pure rotational frequency issues, ie. the engine
• Occurs within a very tight RPM range (3000-3300) = rules out cam timing components
• Happens with and without SC = rules out motor mounts
• Happens with base exhaust, PSE, and aftermarket pipes = vibration is probably upstream of the center muffler
• Seems to happen only with specific throttle input = probably exhaust-related

So going with these assumptions, I got under the car to see if I could find anything that might be prone to vibration. The first thing that caught my eye was the heatshield next to the side muffler. Just for kicks I clamped a vice grip onto it (pic) to change its mass and went out for a drive. There was some traffic so I couldn't test it extensively, but I could not get the vibration to occur! Usually its very easy to reproduce the vibration.

At this point I'm still skeptical of my experiment because of the lack of testing, but I'm hoping some of you could maybe try this as well. I probably won't get another chance until tomorrow at least.

 

Founder's post:

This is some good work here. When I examined the heat shields I just checked for looseness and metal contact. I never considered changing its mass. It could be that it is just vibrating at a certain RPM and torque load. I will try to get my car on a lift this weekend and try to reproduce your results. Can you tell me which shield is the one that you played with? I think the sound is coming from the rear right side, but its tough to be sure.

 

Yeah it felt like the right side to me too so I clamped the passenger side and got the posted results. BTW you should have enough clearance to get to it without a lift.

 

So it seems that the shield may be vibrating and touching the side. Reasonable since the clearance is very tight. I am going to place a small shim in there. It won't survive heat long term, but it will confirm or eliminate the solution. I will jack up my car this weekend and shim it. Stay tuned.

Frank C.

 

Very interesting developments.

Has anybody else confirmed this heat shield experiment? Any more news?

This issue is really starting to get on my nerves. Makes the engine feel really unrefined.

Glad to hear the problem might be as simple as the the heat shield and not something internal to the engine.

 

I am still going to work on the shield, I am trying to figure out what the wedge should be made of so I don't self immolate. I want to make it a permanent fix as I suspect it is the culprit based on sound and the vice grip test result.

 

So glad to hear it's not something inside the engine!

Also is it just the heat shield on one side? I assume the identical heat shield is on the other side, but no noise from there?

 

Stay tuned but it looks like the back right side.

Frank C.

 

Hey guys, just wanted to reiterate that this is still a work in progress, so don't go making any fancy permanent shims/clamps yet I haven't been able to experiment further since I last posted on 10/29, but hope to get to try again within the next 10 days.

If you can or can't reproduce my trial fix, please share your results here in the name of science.