Spark Plug Change Instructions

[mackguyver]

I'm deleting my original post - I took another stab at my 986 plug change in the light of day and wanted to post some tips to keep with the spirit of this topic:

• The KD Tools spark plug sockets (mentioned in a earlier post) worked perfectly for the 986 engine. I used the 11" socket for the 4 rear-most plugs and the 6" for the front 2 plugs. They are worth their weight in gold - no more trying to retrieve a lost socket deep in the engine. The only negative was that the hinged shaft on the 6" requires far more turns because the hinging reduces the effectiveness of each turn.
  
• Plan on removing the wheel well liner held in place by two 5mm plastic nuts - it'll give you much more access to the cramped space.
  
• You'll need to remove the 5mm bolt holding the spark plug connector wires in front of the 2 front-most plugs to get the wire & harness out of the way for full access to the boot and plug.
  
• You'll also need a Phillips head screwdriver to remove a screw holding a u-shaped drain/vent that blocks access to the 5mm hex bolt on the middle plug on the driver's side. If you remove one screw and loosen the other, you can swing it out of the way to get access.
  
• Just about the only tool that will reach the front-most (driver's side) 5mm hex bolt is a traditional 90 degree bent hex wrench, like the ones that come with furniture. Between the body & a very thick hose (or wire), you won't be able to use a hex socket, a foldout hex or any of the elaborate socket extenders and thumb wrenches I tried. You might get away with a low profile 1/4" mini socket or GearWrench type socket. This might not sound like a big deal, but owning multiple hex socket sets, and several folding hex sets, I never bothered to buy the 90 degree hex wrenches and had to run out to get a set to complete the 6th and final plug - very annoying!
  
• Also, and your experience may very, but I found the 5mm hex bolts needed a fair amount of force to "pop" them and then they were easy to turn.
  
• I had Beru plugs from the factory and found some of them to be very tough to get out. Two required maximum torque to get them loose and all were very tight and even "gritty" for the first 5 or 10 turns. I have changed plugs on at least 6 other cars (mostly European) and never had this much difficulty. I don't know if it's the whole "no anti-sieze" thing or what, but it wasn't very comforting and I was very worried about stripping the engine threads.
  
• With the 11" extended socket, I was able to use my torque wrench to snug the plugs to Bosch's 21 ft/lb recommendation for the 4 rear-most plugs. I wasn't able to get enough room to turn the torque wrench in the front of the engine, so I just tightened them by hand to what I felt to be the right torque.
  
• Allow plenty of time (at least an hour) to change the plugs because it's so damned cramped and even with a good worklight, you have to do a lot by feel. If you've only changed plugs in a front engine, you're in for a surprise. I used to think it was a pain to change the plugs near the firewall in my BMW because it was tight...
  

I hope this hellps fellow 986'ers out there. It's a pain, it's dirty, it takes while, but it's not too hard and I'm sure you'll save a ton over what the dealer wants to charge.

Edited July 9, 2008 by mackguyver

[mackguyver]

I edited my last post, but I guess it doesn't show up as a new one, so I'm writing thing to make sure people get to see my tips.

[hantsbad]

Do you need to change the coils with the spark plugs? And if not how do you know when they need to be changed. I am going to be doing my 30,000 mile service and wondering if I need to get the coils.

Thanks

[mackguyver]

Do you need to change the coils with the spark plugs? And if not how do you know when they need to be changed. I am going to be doing my 30,000 mile service and wondering if I need to get the coils.

Thanks

I don't know the answer, but I'd be really surprised if these need to be changed until much later like 90k miles or only if they're defective.

[kristian]

Hi,

Just finished changing the spark plugs. I removed the three screws on the cat to be able to move it back and have more room.

My engine light is on and one of the spark plugs must be missfiring. Does anybody have the numbers for the cylinders so that I know which one it is when I get the code. Also I removed two of the connector wires, was there anything specific I had to do to snap them on. I might have not got them on correctly :(

Thanks

Kristian

1999 carrera 4 convertible 62000 miles

[Loren]

Hi,

Just finished changing the spark plugs. I removed the three screws on the cat to be able to move it back and have more room.

My engine light is on and one of the spark plugs must be missfiring. Does anybody have the numbers for the cylinders so that I know which one it is when I get the code. Also I removed two of the connector wires, was there anything specific I had to do to snap them on. I might have not got them on correctly :(

Thanks

Kristian

1999 carrera 4 convertible 62000 miles

[kristian]

Thanks,

I just finished fixing the problem. The problem was one coil that was not on properly. I had put it on, but it had not snapped on, so it was loose. It was giving me codes for missfires on three cylinders. After I fixed it, it runs great.

I definately recommend taking off the three bolts on the cat converter and pulling it about an inch outward for more room.

Kristian :P

Hi,

Just finished changing the spark plugs. I removed the three screws on the cat to be able to move it back and have more room.

My engine light is on and one of the spark plugs must be missfiring. Does anybody have the numbers for the cylinders so that I know which one it is when I get the code. Also I removed two of the connector wires, was there anything specific I had to do to snap them on. I might have not got them on correctly :(

Thanks

Kristian

1999 carrera 4 convertible 62000 miles

[Porsche_911]

What model and year of car do you have? I just want to make sure to buy Bosch as well if we have the same exact 911. Thank you.

HELP! HELP! HELP!

I'm in the middle of replacing my plugs and am currently working on the passenger side front plug (the hard to reach one). I removed the old plug with no problems but when I went to insert the new plug, I can make it in about four turns and then it stops. I'm afraid it may be Galling up in there.

What should I do? Should I try some never-seize or do I have a more serious problem on my hands.

Any help would be much appreciated. Thank you.

-Nichlolas

[Porsche_911]

I have a 2000 Porsche 911 C4. Does anybody know what brand of spark plus is installed? It can be Beru or Bosch. Thanks!

[Loren]

I have a 2000 Porsche 911 C4. Does anybody know what brand of spark plus is installed? It can be Beru or Bosch. Thanks!

Could be either but Beru was used most often.

[johnbruni]

Do yourself a favor and pick up one of these little helpers. works awesome for getting the bolts out of the coils. also great for interior screws in tight places.

[craig3887]

Problem fixed! Sure enough, the plug had completely galled about 1/16" on the first thread. I am using the Beru plugs on my 01 boxster, as that is what Pelican parts claims is OEM. However, the old plugs I took out were indeed Bosch, so I guess Pelican is incorrect. The Beru plugs have stainless steel threads as opposed to the stronger and less-galling copper or brass threads of the Bosch plugs. The key here is, you need to use Never-Seize on the Beru plugs to make sure that you don't gall the internal threading in the engine, cause then you have a BIG BIG problem like I did today. Also, do not even think about using a wrench to tighten the plugs until the very last turn. The plug must go in by hand, but if for some reason it should not then you have to go to Plan B.

Porsche uses Beru and Bosch as their original equipment supplier for spark plugs. When I did mine last year i had four bosch plugs and two beru on my car. Pelican parts is correct with the beru plugs but I prefer the bosch ones.

[masq]

So what is up with no anti-sieze?

I found the following written on Pelican Parts' website. So don't use any!

[Stefan]

Note that according to Porsche TSB #2870, the Beru spark plugs are no longer recommended.

As of MY 1999.

Spark plug types:

New: Bosch - FGR 6 KQC

Previous: Bosch - FR 6 LDC -or- Beru 14 FR 6 LDU

[ecgross1]

I'd second removing the mufflers. Took me 15 minutes to drop both mufflers, which makes changing all six plugs so easy it is ridiculous. Finished the entire procedure and was terrorizing the neighborhood with my car sans mufflers in less than two hours. While the plugs can be changed without dropping the mufflers, I'll refer you to all those who spent 4 - 6 hours doing the work for an endorsement of that method. Almost makes me cry reading about all the suffering trying to reach those back plugs when the mufflers go off and back on so easily in less than 30 minutes. Mine has had an erratic idle at times. All of the coils showed superficial cracking after 80,000 miles in the Arizona heat, but I am pretty sure they are still good - and just a bit too expensive to replace for fun. I have oil leaking from a couple of the plug tubes that I suspect may be getting in the coils and could be the cause.

[PJorgen]

I'd second removing the mufflers. Took me 15 minutes to drop both mufflers, which makes changing all six plugs so easy it is ridiculous. Finished the entire procedure and was terrorizing the neighborhood with my car sans mufflers in less than two hours. While the plugs can be changed without dropping the mufflers, I'll refer you to all those who spent 4 - 6 hours doing the work for an endorsement of that method. Almost makes me cry reading about all the suffering trying to reach those back plugs when the mufflers go off and back on so easily in less than 30 minutes. Mine has had an erratic idle at times. All of the coils showed superficial cracking after 80,000 miles in the Arizona heat, but I am pretty sure they are still good - and just a bit too expensive to replace for fun. I have oil leaking from a couple of the plug tubes that I suspect may be getting in the coils and could be the cause.

Seems like removing the mufflers makes sense, but are there any issues with reinstalling them? Do they require new gaskets, any problems with leaks?

Also - what is the torque spec for the muffler bolts?

[Loren]

No gaskets.

See the write-up here

[PJorgen]

No gaskets.

See the write-up here

Thanks! Once again your reply is right on target.

[jasper]

I've been quoted a NGK spark plug part number of BKR6EIX for my MY2002 996 normal. Is this a good number for a good plug for my car?

thanks

jasper

[jasper]

OK - after some more research, the NGK plugs while probably fine, are not Porsche specified. I went with the Bosch copper electrode parts on the advice of my indy. These are the ones with the 4 tabs on them instead of the one tab on the NGK pieces.

Also, it appears that the 3.4 litre cars use heat range 6 plugs, while the 3.6 litre cars use heat range 5.

Long story short - I installed Bosch Super FGR5KQEO, although the plugs I removed were FGR6. They were burned up pretty god by the way.

On the install side, I didn't remove the mufflers and frankly I don't think it would have been that much less work if I did. I only struggled a bit with number 1. The rest were EZ peezy.

My coilpacks were held down with torx head cap screws. This worked out great for me since I had a set of short torx bits like what you would put in the end of a multi driver screwdriver. These easily fit into the head of the bolts, and then I used a 8 mm ratcheting spanner to work the bit round.

On the plugs themselves I used a normal 5/8 plug socket , then a 3/8 drive swivel, then a 3" extension, then my 3/8 ratchet. There were *zero* issues with access to the plugs using this setup.

Yes, it did take me nearly 4 hours start to finish, and yes number 1 (pass side rear) was difficult to access, but overall this wasn't the most difficult job I've done.

[Loren]

On the install side, I didn't remove the mufflers and frankly I don't think it would have been that much less work if I did. I only struggled a bit with number 1. The rest were EZ peezy.

:lol: you must have small hands (smaller than mine)!

[venturawildes]

Just got finished changing the sparks on my 2002 cab, personally I do not know how anyone can do this without taking the mufflers off. It took me about 5 minutes per side to drop the mufflers. The outer most plug on the passenger side was still challenging with the muffler off, with it on I do not see how it could be done. If you want to change the plugs with a minimum of cussing and fussing, drop the mufflers. Easy breazy

[raffi]

Hey Loren,

do you have the part #s for 2005 997 carrera S spark plugs?

also do you know if it is basically the same procedure as for the 996?

thanks alot

[Loren]

Hey Loren,

do you have the part #s for 2005 997 carrera S spark plugs?

also do you know if it is basically the same procedure as for the 996?

thanks alot

The 997-1 'S' cars use the same spark plug.

999.170.223.90 Spark Plug FGR 5KQE0

Procedure is the same as the 996 series.

[jamesanderson84]

Just did this job yesterday. Not easy - but not too difficult if you take it steady.

Learnings:

I dropped the mufflers. Cant see how you'd do the job without dropping them. It added some time and fiddling - but it made it doable versus being a swearfest.

Be careful about the extension bars you connect. The middle tube on the driver side and the rearmost tube on the passenger side (US spec) align with the muffler brackets and I ended up with a combination that could not be removed. The extension bar was tight to the spark plug socket and it took some ingenuity and swearing to get them apart.

I installed NGK plugs. I removed Berus which looked to be in good shape.

Here's to the good news - the difference is HUGE. The engine is quieter - the power delivery is smoother and much more even. It makes it a much better driving experience.