So every now and then 1-2 months or a little longer go by, and my car starts shaking, and won't gain much speed for a couple minutes, check engine light comes on for cylinder 3 misfire. New spark plugs, coil pack, wires, ect. I bought a compression test kit today, was going to use it until I pulled the wires out of all cylinders. All have rust on the spark plug walls except the 1st cylinder. I found a way to clean the rust off.

Should I do a compression test still?

 

Yes do the compression test anyway.
it is always a good idea.

 

Ok, I will do this tomorrow if I have the right fitting to do the compression test. I thought I could remove the rust on the spark plug walls, but I can't. Somebody said to use a steal brush, but I couldn't find one that looked like it would fit so I used a tough bristle brush, and some wd-40, but no luck. I would use steal wool, but I know that stuff will leave shavings all over in the spark plug well, and it lights on fire easily. I don't want any particles in their. Is it ok to leave the rust on the spark plug walls?

 

id be curious as to how it got in there in the first place but why not keep the plug in
wire brush it
then use a vac to clean it out...

 

I just tried steal wool, but that isn't helping.

 

guess just leave it in there.

 

I assume you're talking about the metal tubes that lead down to where the spark plug goes.

The spark plug sleeves are only about $9 each, plus about $20 for a new valve cover gasket
and some lock-tite and maybe new seals ($6 each if needed), but replacement might be tricky
without BMW Special Tool 12 1 210 (which is actually 12 1 211 + 12 1 212).
Could probably find two tubes the right diameter to take their place for driving in the sleeves, though.

 

Having said that, if the rust hasn't perforated the sleeves, then should
probably consider them not broken, therefore doesn't need fixing.

 

Update: I didn't see cristo's posts till today, and I was on the highway last night maintaining 65mph when all the sudden the check engine light came on for cylinder 3 misfire again, started shaking, and all that, tried to go faster, but car shaked worse, and would slowly pick up more speed. Anyway I pulled over, turned the car off, pulled a few spark plug wires off, and I saw some wetness in their so I started sniffing, smelled like gas. So I am guessing the gas is what made those walls rusty, and not sure how the gas is getting in their. I'm guessing maybe bad fuel injectors, but this is an intermittent issue.

 

If you're seeing wetness and smelling gas in the spark plug tubes, then either
the seal between the top of the tubes and the valve cover gasket (see part
5 in the first link below), the seating of the tubes (see part 2 in the second link)
into the cylinder head, or the integrity of the tubes (rust holes?) is likely to blame
for the gas/wetness. The gas won't cause rust, but water will.

http://realoem.com/bmw/showparts.do?...87&hg=11&fg=15

http://realoem.com/bmw/showparts.do?...06&hg=11&fg=15

BTW, how did the compression test go?

 

Ok. I didn't do a compression test cause I figured it was something major wrong, and returned the compression test kit.

 

Actually, a bad result on a compresssion test would point to something major wrong,
like need for valve job, piston rings, etc.

If moisture is causing a misfire, then clean and dry the spark plug boots and use some
dielectric grease on the inside rubber of the boots before putting back on the spark
plug. That may solve the problem while you're sorting out the source of the moisture.

Also, if you have a consistent misfire in one cylinder, then unburned gas from that cylinder
can cause the gasoline smell with nothing else wrong.

 

When the misfire, and shaking occurs its just for like 1-2 min, and then everything is fine. When I let the car sit for a while, and get back in the engine light is out or goes out soon after driving. Its not consistent.

Should I start with replacing the tubes, and seals? Also what special tool do I need, and should I replace the valve cover gasket too while I have it apart? Also do you need to use special stuff to hold the valve gasket in place?

I plan on driving on the highway again today, and this time I will take my video camera to help diagnose things.

 

I would probably take the valve cover off so I could see if the tubes are intact and
in place, would probably replace the seals since they're cheap and easy. You'd need
a new valve cover gasket as re-used ones usually leak.

This is a MINI Cooper, not a MINI Cooper S, right?

I've never done this, but if the tubes are loose, maybe they could be tapped back
into place carefully and re-sealed with Loctite.
If that doesn't do it or if there are rusted through spots in the tubes, the
official replacement calls for a special BMW tool to pull off the old tubes
(11-8-500) and another two-piece tool to drive the new ones in (12-1-210)
(see page 116-4 of the Bentley Manual) and Loctite 277 sealing compound at the
base of the tube where it goes into the cylinder head.

 

Yea, base mini cooper. Where can I buy the tools for the tubes? Also isn't their a special grease or paste to use for new valve cover gaskets?

If I am going to remove the valve cover I my as well replace the tubes, and seals right away. I hate knowing that their is rust on the spark plug walls.

 

As for the valve cover, Bentley says:

Replace valve cover gasket
Replace spark plug hole sealing grommets in valve cover.
Clean gasket mating faces. Coat lightly with oil.
Replace valve cover mounting bolts or insulators if damaged.
Tighten valve mounting bolts in sequence from inside to outside
(but there is no specific diagram for the exact sequence - so work
up to the specified torque with a few go-arounds inside to outside).
Inspect ignition coil pack insulators. Replace if damaged.
Tightening torques:
ignition coil pack to valve cover, and valve cover to cylinder head
are both only 12Nm (9 ft-lb).
When reinstalling ignition wires, make sure that they snap securely into place.



So that sounds extremely straight forward and easy, and it should be easy in actuality.



Regarding the spark plug sleeves:

First, a little rust on the inside of the sleeve is probably a better insulator than bare metal,
so maybe do nothing, but if the sleeves are loose or are perforated by rust, that's a different story.

Some dealers will order tools for you, but be prepared for a high cost and/or a reluctance to order.
Most dealers will not loan or rent their tools or have new ones available for immediate sale.
It might actually be more cost-effective to have the dealer or a MINI-familiar mechanic replace the sleeves if necessary.
It should take only an hour of labour plus low cost for the sleeves and gaskets, but I'd guess
they'll probably charge 2-3 hours labour since they have most people over a barrel on this.
Hell, they might even charge you for the time for the loctite to set before they replace the cover.
I looked on the internet for a while for the 12-1-120 set (consists of 12-1-121 and 12-1-122) without success.
Maybe someone with more experience can chime in with a source or more likely, a practical work-around
solution with more readily accessible items.

The specific instructions for pressing the tubes into the cylinder head basically are as follows:

Remove valve cover. Remove spark plug.
Use tool 11-8-500 to pull out the spark plug sleeve (along with a slide hammer adapter)
Clean area around spark plug bore
Apply 3 mm thick bead of Loctite 277 sealing compound at
distance of about 1 mm from end of spark plug sleeve
Screw tool 12-1-212 or equivalent guide into spark plug hole
Carefully install spark plug sleeve
Fit with special tool 12-1-211 or equivalent driver
Drive spark plug sleeve into cylinder head bore
-note sleeve is installed correctly when special tool
12 1 211 makes contact with special tool 12 - 212.


So, the guide is a basically a cylinder that fits loosely inside the spark plug sleeve and screws into the spark plug hole
and the driver is a tube that slips over the guide and fits flushly against the outside of the guide and the inside of the
spark plug sleeve with a larger diameter step up a few inches (the length of the spark plug tube minus the press-in length)
up the guide to drive in the spark plug sleeve.

Alternatively, one tube that just fits inside the spark plug sleeve and another the same inner and outer diameter of the
spark plug sleeve to slide over the first tube and abutt the spark plug sleeve and a steady hand with care and attention
to keep things lined up correctly would probably work.

 

From your responses i think the best course of option would be to take it to a shop and have them investigate it.
would make your life a good bit easier.

 

I am home, car didn't act up. I would take it somewhere, but don't feel like spending an arm and a leg. Also I like getting more experience with my car. I replaced the crankshaft pulley, brakes, rotors, rear control arms, and other stuff myself. I think I can handle spark plug tubes, seals, and the valve gasket.