Stefan

My fan mod is not intended to fix a broken relay. It is intended to fix a broken ballast resistor, which is a common problem and the source of many cars running too hot. It works automatically and without the driver having to think about it. Fixing a relay is trivial but fixing the ballast resistor is more involved and requires buying a fairly expensive part.

If you don't want to have to operate a manual switch you can try my radiator cooling fan hack. It should take about 5 minutes to implement.

http://www.ppbb.com/boards/ppbbphp/showfla...;Number=1509504

The switch in my fan mod is not to correct a non functioning fan system or relay. Fixing the relay fault is quite simple and should be done with new relays when necessary. The fan mod is to turn on the HIGH speed fans at will and at any temperature. Or you can eliminate the switch altogether and have the high speed fans come on below a certain engine speed, vehicle speed, etc.

If you don't want to have to operate a manual switch you can try my radiator cooling fan hack. It should take about 5 minutes to implement.

http://www.ppbb.com/boards/ppbbphp/showfla...;Number=1509504

Check out this fan hack writeup I did on PPBB. It should be the same for the 996.

http://www.ppbb.com/boards/ppbbphp/showfla...;Number=1509504

Other than the motor mount, the problem could be due to a need to bleed the clutch (clutch is not fully disengaging) or misadjusted shift cables,

Funny, I had that same awful sound. I took out the starter and cleaned and lubed the shaft at the opposite end of the one you indicate and the problem has been gone ever since (about 3 weeks now).

I cleaned the part with WD-40 and lubed it with standard high-temp synthetic axle grease. To get at the shaft I had to pull and twist the gear.

It could be a leak from the joint just under the reservoir. Have you had any work done on the car lately? Often the last place touched is the first place to look.

I recently discovered that the latch connecting the reservoir to the pipe below was not properly latched. The two tabs should line up. That may not be it but it is fairly easy to check and easy to fix.

How about checking the lower AOS bellows for tears? That is common and the mechanics may not have checked there for leaks.

Did you properly wire up the resonance flap? That is supposed to open at 3k RPM and if it isn't that could cause a stumble.

You can tell if it's working by looking at the second intake plenum (closest to the front of the car), revving the car up and seeing if the rod turns.

I guess I'm too late but Maurice, you're welcome to use mine any time.

If you think the problem is the MAF then try unplugging the MAF and see if the problem goes away. I doubt that the problem is the MAF. I would start by removing the air filter and shaking it out since that is the easiest to do. If it hasn't been replaced in a while and you have an extra lying around then I would replace it.

My guess is that you're using the wrong programming codes. That would cause this symptom.

I still wouldn't rule out the possibility of an air leak but it almost sounds like there is a short to B+ in the idle circuit or a faulty ground. It should be possible to test both of these.

With an OBD2 reader you can read the air flow (as measured by the MAF) during idle. If it is the same when the problem is happening and when it's not then you definitely have an air leak.

If there is no air leak, you can narrow down the problem by testing to see whether or not the ECM is telling the ICV to idle higher. This you can do by testing the voltage on the idle control valve input. I think this might be pins 1 & 3 but I only have a really bad faded wiring diagram available to me right now. If the input to the ICV is higher when the problem is happening then the problem is not mechanical. In that case, I would diagnose a possible short in the idle signal line (ECM to ICV).

I notice that if I undo the roof locking handle the noise goes away regardless of how rough the road is.

This particular problem I solved by lubricating the latch mechanism.

It sounds like the dealer is shooting in the dark. Did they give a reason as to why they think it is the DME? DME failure is pretty rare. It is more likely that you have a leak somewhere in the intake.

If you buy a DME, it is unlikely that you will be able to return it when it doesn't solve the problem.

If you insist on replacing the DME, I have a used one with all of the codes that I'd be willing to sell. But again, I don't think it's going to solve the problem. The dealer should be able to tell you what signals from the DME are out of spec and causing the problem. If not, you're just burning money.

same thing this guy is describing but a few months ago, while driving, I had a sudden change of clutch pedal feeling and it has just gotten worse ever since. Now, it slips under medium to heavy load and when in a high gear . . . . really annoying!!!

That is not the same problem. The original problem description here was that the clutch wasn't properly disengaging. That sounds to me like a problem with the hydraulics and from the picture, it doesn't look like the crack could cause that symptom.

Your issue is that the clutch is not properly engaging, which could be a worn clutch.

You really have to prioritize money and reliability. The cheapest (by far) option is to replace your engine with a used 2.5L. The engine should cost you about $2k and installation $2k or slightly more. You get almost identical reliability by going to a 3.2L engine. The cost will be higher ($1k more for the engine and $1k more for installation) but you will obviously have more power.

As far as installing the 2.9L Raby engine, this is probably the most expensive option. You can replace your engine with used 2.5L engines three times before you get to the cost of installing one of his.

I replaced my 2.5L engine with a 3.4L 996 engine and am happy with it. I didn't buy any reliability either, just power. The installation was as straightforward as it gets for installing a different engine.

On the 1999, the throttle body is not involved in the idle. It is controlled separately by the idle control valve (ICV) which is easy to remove (2 torx bolts) and clean. It is common for them to get gunked up over time and stop operating properly. I would check that first as it is the easiest to do.

A 1999 3.4 996 engine is approximately 550 lbs.. The 3.6 is probably similar.

Does anyone know the approx. shipping weight of a 996 engine?

AutoHausAz has good prices on things like this. They have both front and rear for around $26 apiece.

Check the clutch switch. If this malfunctions, the car won't start. They have been known to stick.

Alarm unit is nice and dry inside, no sign of any dampness so it looks like the Porsche Centre after the holidays.

Don't forget to check the fuse on the immobilizer as Maurice suggested. Also try fussing with the clutch switch as it sometimes sticks and that would cause the car to not start.

Before you replace the sensor, I would check the wiring to ensure that it is correct. (FWIW, "special tool 9616" is not required for this procedure; it just makes it easier).

1 Check wiring from pressure sensor to DME control module for short to ground.

1. Connect special tool 9616 to wiring harness (DME control module connector).

2. Remove connector of pressure sensor.

3. Connect ohmmeter to special tool 9616, pin 72, and ground. Display: Infinity ohms If 0 - 5 ohms is displayed, check wiring harness for chafing and pinching damage.

2 Check wiring from pressure sensor to DME control module for short to B+.

1. Connect special tool 9616 to wiring harness (DME control module connector).

2. Remove connector of pressure sensor.

3. Connect voltmeter to special tool 9616, pin 72, and ground. Display: 0 V If battery voltage is displayed, check wiring harness for chafing and pinching damage.

You can also get better access to these different jack points by driving the rear wheels up onto 2x6 boards before you do the jacking.

You can wire the left side lighting wiring from the right side lighting wiring.

For the motor mount, check out Pedro's Garage (scroll down to "enthusiasts engine mount").

http://www.pedrosgarage.com/Site/Performance%20Products.html