RRocket

Not sure if it is water intrusion nor whether this is the exact cause of the CEL. They have three protruding rubber rings that are supposed to keep the elements out, but who knows what condition they are in.

No tools required to change the boot. You need to twist at the base closest to the coil housing to get the rubber to break the seal and then it should snap out when pulling on the boot. Re-install the boot and push in until you feel/hear a click.

Also, I find it easier to disconnect the coilpack wiring prior to removing the fasteners holding them in place. Make sure you also get a solid click when reconnecting. The large rubber boots on the end of the connector get in the way and make it difficult to snap back in place. I usually peel or slide the rubber back, snap the connector in place, then slide the rubber cover back into place.

As always, your replies are excellent.

What about dielectric grease? Yes or no? On the boots only? On the connectors?

You can test the resistance of the coilpack with a simple multimeter. With the leads on the outer of 3 pins, you should get about 0.7 Ohm.

What happens sometimes is a rip or pinhole develops in the rubber insulating boot and it arcs into the head. I've pulled coilpacks where people have tried to fix it with electrical tape but the output voltage is much higher than tape is designed for. About $15 for a new boot or about $40 for the whole unit.

Excellent info re: .7 Ohm However, when dry they could conceivably check as "ok", but when damp is when the problem might manifest itself, correct?

As far as replacing the boots themselves....how do they attach to the coil pack?

Thanks again everyone for the excellent info.

Car sat in the rain most of the evening and when I went to drive it I got a flashing then solid CEL. It felt like a misfire. TorquePro app told me it was P0301; cylinder 1 misfire.

I'm guessing I have a cracked/damage coil pack? And to confirm, cylinder 1 is the cylinder closest to the back of the car on the driver's side?

Thoughts before I buy parts??

Thanks!

So you literally have to drop the tranny? Or is there enough room to press it out while still installed?

Man...that looks like a PITA!!

Here's a DIY for the Boxster. Am I assuming correctly that the process for the 996 is very similar? Part even looks quite similar.

http://www.pedrosgarage.com/Site_3/Install_Front_Engine_Mount.html

Manual or tip?

For the tip I don't know. For the manual you have to drop the transmission and take it to a shop to have them press out the old mount and press in a new one.

However, there are alternatives.

http://forums.rennlist.com/rennforums/996-forum/782771-increase-996-chassis-stability-and-enhance-shifter-feel-and-accuracy.html

http://forums.rennlist.com/rennforums/996-forum/811134-transmission-mount-urethane-fill-diy.html

Ugh...You have to drop the tranny? That's a bit beyond what I was hoping. That tranny insert might be the way to go....

Any idea if the tranny mount is a possible DIY? I'll be on a hoist..

I just picked up a new to me 1999 911. When I let off the throttle, there is excessive drive line slop. In addition, at idle there is more vibration than should be expected. Therefore, I'd like to replace the engine mounts and the transmission mount.

As far as the required parts, can anyone point me in the right direction? As far as the install, is there a DIY?

I'll have the car on a hoist this week putting my my Fister Ds, so I intend to do the mounts at the same time.

Thanks! !