Spark Plug Pipes M96.20
 

Hi Gents,

after a spark plugs replacement, the engine started to misfiring at low rpm and CEL went on.

When I visually inspected coils I found the spark plug's housing on cylinder 1 & 4 filled of oil.

Endoscope check found cracks on the plastic pipes that seal the valve cover with the cylinder head by the means of two o-rings.

I went to dealer and bought two new pipes, o-rings and two new coil ends that have been "fried" in oil and got crispy..

But my challeng is now to get the pipes out of their housing. I tried to use some home made extraction tool but didn't work out. Some of you have ideas about how to get that .... out of there? I have the car on the jacks and don't have any will to get it to the dealer and spend a fortune to have it repaired. Car is a 986 2.5 1997. Hint and tips?
marco

I have seen some folks that use a 1" boat transom plug to pull the spark plug tubes out, as described here on Pedro's site:

Change Spark Plugs & Tubes

I have got new plugs, tubes, and O-rings from Pelican and I am going to try and get one of these plugs before I change them out.

Steve

I tried the transom plug and it kinda worked some of the time but I had a problem getting it to grip tightly enough. what worked really well was the 1" rubber arbor from my drum sander kit. It has an actual nut for compressing the rubber rather than just a little twisty bar like the transom plug.

When I did this job I replaced all the tubes and all the o-rings. Even if you only want to replace the tubes that are actually cracked (a decision you would likely come to regret) you should still replace all the o-rings while you are in there. How long do you want to spend chasing plug tube leaks?

I know I sound like a broken record on this, but I would really encourage you to do a search of the forum on this topic (top bar, "Search" with a little down arrow beside it). There have been several threads that I think you would find helpful.

I have seen threads where they buy a plumbing connector with a 3/4" thread. They turn it in till it starts to grip the tube well and then pull it out. The goal is to get all of the tube out - not leaving plastic under the cam cover.

Well... and that's what really happened... Murphy's law...


I went to the dealer and they borrow me the tool, a nut with two rubber inserts that expands inside the tubes to gain the right grip to get them out with the help of a lever.

Obviously, as soon as the rubber expanded, the previous cracked tubes collapsed and the result is to have some plastic pieces going around the engine. Ok, not so big pieces that can cause major fault so I decided to leave them there and pick them up at next oil change when I will get the oil pan down.

Anyway, tubes replaced, spark plugs replaced (original beru with NGK brk6ek). Starting up the engine, with my surprise, the engine still misfiring between idle and 2000 rpm. Diagnosys shows cyl 1 misfiring with some random other cylinders but in less number. If I push down the throttle when the engine is within 1000 and 2000 rpm, misfiring is unaccetptable and if I keep throttle down, the CEL goes on (first blinking than solid). If I gently push the throttle misfiring issue is not present.

After 2000 rpm, engine is clear, powerful and no problems are shown.

What could have gone wrong with the engine after a spark plug replacement? Coils seems to be ok, I also changed them position but misfiring still remain at cyl 1. None of those issues were present prior the maintenance. Any idea???

Thanks

Marco

Try a different plug at no 1 cyl.

You think it could be a plug problem? I visually checked them for cracks but seemed ok. They are new..

I just grabbed an appropriate sized impact socket, turned it around and put it in the tube and turned until it loosed the tube and pulled right out without issue every time. Worked like a charm and just grabbed the first thing that was within reach...

I have a 3/4 pipe T fitting with threaded insert I plan to use when the time comes. I posted a pic of it previously if you want to search to find it.