Stefan

Exhaust flow is shown in this diagram

I will be connecting an additional pipe directly into the outer chamber, thus partially bypassing (2) and (3) in the diagram.

I am planning to do a very similar mod. But instead of dumping the bypassed exhaust straight out, I am going to dump it into the outer chamber. So I will be bypassing the inner chamber of the exhaust, electrically controlled.

I would remove the throttle body and give it a good cleaning. That might be what he is trying to replace. It is a common problem that they get gunked up over time. I highly doubt that it needs to be replaced.

This is not a particularly difficult job and you should be able to fumble your way through it. :P

Thanks for the update, Chris. I hadn't read the other thread.

I would start trying to narrow down the problem. I would do the following things, in this order:

Put the old bulbs in and try turning up the cluster brightness :)

Test the old and new bulbs outside of the car to make sure they work

Check the cluster bulb contacts for melting and/or corrosion

Test the output of the cluster with a voltmeter to see if it is actually putting out a voltage

Try a friend's cluster to see if that one works

Connect the car to a PST2 or PIWIS to see if there are any faults

Do you have the part number for the cable? I have the same problem on my Boxster and I cannot find the part on any part diagram.

Are you saying that the original bulbs no longer work? If it's just the LEDs that don't work, it is possible that the polarity is backward.

It's good to hear that K&N is stepping up to help you. For your reference, they have a page about MAFs:

http://www.knfilters.com/MAF/massair.htm

Good luck and keep us posted on what happens.

Here is a writeup I did on this topic:

http://www.ppbb.com/boards/ppbbphp/showfla...;Number=1171280

Thanks for the discussion, folks. It sounds like we're all dealing with the same sort of issues. And it's very helpful to hear how others have solved them.

I have been procrastinating on finishing the header replacement on my car for several reasons.

On both sides I got the nuts off with considerable effort (torch, dremel, etc.) and on both sides the cat refused to separate from the header. The driver's side eventually separated after a bunch of driving with no nuts holding them together. After it separated I put on a single nut to hold it on until I'm ready to complete the job. However, I found that after less than a month the nut (which came with the aftermarket headers I got from eBay) is completely corroded.

So I will get better quality nuts and bolts to hold the headers before I will complete this job. There is no point in using cheap quality fasteners given the amount of time and money we have spent on the rest of the job.

I am also debating the merits of heat wrapping the headers before installing them. I am also considering having them ceramic coated.

I have been driving with no nuts holding the passenger side header to the cat and even after a couple of weeks it hasn't separated. It looks like I will have to use more brute force to get it off.

Thanks for the thoughtful DIY, Dana.

I don't know why the dealer would charge 4 hours to remove the top when some board members have been able to remove it in under 15 minutes. There is no reason I know of why they would have to remove the canvas from the frame, which is certainly a time consuming operation but unnecessary in this case.

I would remove the door panel and see if you can see what the problem is with the regulator. It could be broken but it also could just be misaligned and hitting something in which case you may be able to fix it without replacing it.

One way to find a vacuum leak is to use flammable gas, such as from a torch. You wave the (unlit) torch around in the suspect areas of the engine compartment. When the gas gets sucked in, the idle speed goes up.

Make sure you are turning the nuts in the correct directions. Otherwise you will have to redouble your efforts. :)

You could also just replace the rear window. That is a much easier DIY.

See: http://www.renntech.org/forums/index.php?showtopic=11302

The DME "upgrade" (really a software change to correctly interpret the different values coming from the MAF) should not affect ignition timing, which I believe is all the GIAC is doing. So you should be able to get a free GIAC remap.

I'm not sure I understand RFM's response but the nuts are stuck because they are screwed together. You can use two wrenches to separate the nuts then they will both move freely.

There shouldn't be any appreciable amount of oil in the intake unless the air oil separator is going bad. I would check the throttle body to see if it is gunked with oil.

I hadn't wrapped the A/C line because I guess I didn't read that thread. It makes perfect sense and I will look into it.

As to the header wrap, that is also a well founded idea. Getting the heat away from the engine (and the engine compartment) efficiently is important and heat wrap definitely helps. Whether or not it makes a perceptible difference I do not know.

I tried hammering a screwdriver between the header and the cat and it wouldn't go in. I didn't want to hit it too hard because I was worried about the O2 sensor. I will get it apart, one way or another. I'm just happy to have gotten that ridiculously welded nut off. I really had to destroy it before it would budge.

I got the last header to cat nut off today but the header seems to be fused to the cat nevertheless. I am going to drive around that way and hopefully the heat and vibration will loosen them from each other.

The torque fo the exhaust manifold to cylinder head is 25 nm (19 ft. lb.).

The last nut connecting the header to the cats is really hard to get at so I haven't done that yet. The rest I was able to remove essentially by weakening the nuts by cutting into them with a dremel, heating them up with a torch, and twisting with vice grips.

I haven't removed any of the studs from the cats.

For non eGas cars such as the 1999, cleaning the throttle body will almost never affect idle. I don't mean to doubt that cleaning your throttle body will make your car run more smoothly but I don't think it will fix your idle problem.

Since the problem was described as an idle problem, I would definitely start with the idle control valve (ICV). It can be quickly and easily removed.

"Will not idle without pressing the gas pedal" sounds exactly like a stuck ICV.

Cleaning the ICV is an easy DIY. All you need for tools is a Torx screwdriver. It is right on the top of the engine so it is easy to access.

One source of noises with the top down is the little rubber bumpers that protrude from the back of the roll bar on either side. The top rubs against them. A little lubricant solves that problem.

It sounds like some wet electronics dried out. If that is the case you might want to track down that leak before it causes bigger (and more expensive) problems.

I always say to people that are thinking of upsizing their wheels: check out the prices of the bigger diameter tires first. You may be astounded at how expensive they are.