E46 Coil pack BOOT question

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So I hope I didn't create a NEW problem while trying to troubleshoot another.

So I got a P0302 code (misfire Cyl 2 ) with CEL and shaky idle, and I was going to to swap out coils 2 and 3 if the Code moves to #3 cylinder to make sure (if) it IS a coil pack.

I had trouble getting coil pack 2 and 3 out so I tried coil 1 and it came out really easy BUT when I finally got the coil 2 out to swap with it, I noticed that the coil 1 looked different than coil 2 and looks like its (coil 1's) boot was missing? did it stay with the plug?

A quick search shows this can happen with these coil packs.

SEE PIC (Coil pack 2 on left (normal) and 1 on right) POST CONTINUES BELOW PIC.


what happened there?

Anyway, I pushed it back on to the same cylinder, and finally got 3 out. (looked normal, like 2 )
So now, I swapped 2 and 3 and started car - same symptoms, shaky idle but RPMs steady - BUT NO CEL yet -
so I guess It will take a few drive cycles for the CEL to come back on?

(BTW I erased the previous code P0302)

So, as of now, expecting CEL and expecting it to be P0203 which will show me it really is a bad coil on Cyl 2.

But in the meantime I am worried about why that coil pack #1 looked weird as if something is missing from it. it's all hard plastic and looked like the rubber surround was missing. ???

It was also a bit wet...oil?

Anyway, I pushed it back in, and it felt like it seated well. I hope it will continue to work as before..

From a quick search I did, I don't think one can buy these boots separately if needed. (Bosch) . One CAN buy separate boots for Bremi coils (up to 2003), apparently. ECS tuning chat could not find a separate boot for Bosch.

If I don't get any UNEXPECTED codes for cyl 1, due to the boot issue, should I just leave it alone? or would you change it due to the little wetness I saw? there was no oil to be seen in cyl 1 hole, but I am thinking something must have made it separate from the boot so easily...
 
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I would just pull #1 again and look down the hole with a flashlight and see if the boot just stuck to the plug.
 
Did that, and yeah - although it's not in focus, I assume that black surrounding circle around the plug is the boot. (didn't see such in other SP "holes") - Thanks, Overkill!
(post continues below pic)



UPDATE:
Drove car around - no new CEL/SES yet. Seems almost normal while driving, but idles weak-ish. RPMs at idle steady.
Car def. has a bit of power loss uphill. One can hear a change in the engine "tone" a few seconds after car starts.
Probably will require more driving, overnight off, etc for the SES come back on. I have no clue what kind of drive cycle is needed on these cars for that.
 
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The oil on the boots is due to valve cover leaking -the gaskets that keep the oil out of the plug wells are probably cooked. Easy replacement, then put on new boots if necessary .
 
What would be the best way to remove that stuck boot from cylinder 1 when you need to do it? Long forceps?
 
Long Reach needle pliers, according to owners of BMTroubleYous
- they're like 11" long and skinny.
 
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Ugh - I am hoping it will only be a bad coil -still no CEL to confirm it, might have to drive around more.
Perhaps it was stupid on my part to ERASE the P0302 code...
It might have just "moved" to a P0303 if I let it stay on, and swapped coils? all i can do now it drive it and wait for the CEL to reappear.

Car only has 47k miles...
Guess VCG could be done, if plugs are fouled. IDK if i have the courage to DIY pulling plugs and checking.. I guess I can try, huh?
 
Originally Posted By: 97tbird
Ugh - I am hoping it will only be a bad coil -still no CEL to confirm it, might have to drive around more.
Perhaps it was stupid on my part to ERASE the P0302 code...
It might have just "moved" to a P0303 if I let it stay on, and swapped coils? all i can do now it drive it and wait for the CEL to reappear.

Car only has 47k miles...
Guess VCG could be done, if plugs are fouled. IDK if i have the courage to DIY pulling plugs and checking.. I guess I can try, huh?


It shouldn't matter whether you cleared the codes or not. If the computer detects a misfire, it will record and report it.


As for the rest- DIY spark plugs really isn't hard at all. The leaking valve cover gasket won't "foul" them, but will soak the outside of them in oil, ruining the coil boots. Replace the valve cover gasket, clean the oil out of the plug wells, replace the plugs if they're anywhere near due and continue with the misfire diagnosis.
 
The thing is, i think the car still feels the same way as before, when the CEL was on. (Not the FIRST time it came on, then it was idling bad a shaking a lot, but after that it settled into a nice almost normal rhythm on idle, but not having quite the normal amount of power while driving; this was all with the INITIAL CEL.
(misfire cyl. 2)

Then I erased the code, swapped coils 2 (of the misfiring cylinder) and 3
(so now cyl 3 has suspected bad coil pack, and cyl 2 has the good coil pack from cyl 3)

So after that the car still behaves like before (while the initial CEL was on), but NO check engine light yet...
Today, it almost felt NORMAL, (but not quite)...

IDK what to make of it. From all the reading i've done, most ppl got the "new" CEL right after they swapped the coil packs, with the new cylinder (with the suspect CP) reported as a misfiring cylinder - IOW, the code "followed" where the bad CP went. But I am not sure if these people swapped CPs while the initial CEL was ON or whether they cleared/erased it like I did.

The manual that came with the scanner says most cars need several driving cycles under different conditions to detect a condition and for the CEL to come back on...
I haven't driven the car MUCH after the coil swap.

(The plug boot thing / boot being wet on cyl 1 is a side story, and that cyl was not involved in the whole main issue, but I guess I became aware of something that needs attn in the near future... But I first want to get this stupid CEL thing sorted out and resolve that - if it's the #2 coil pack being bad or not...)
 
On our '08 E60, when a coil failed I did exactly what you did (minus the boot issue). The car relit the CEL for the new cylinder misfire almost immediately. In our case I replaced the valve cover gasket, a couple other related gaskets, and all 6 coils and plugs. I didn't want to have to do that job again anytime soon.
 
That is why I am confused. Why isn't the CEL re-lit? And why did it feel ALMOST normal today?
Did you erase the original code before swapping coils?

A misfiring cylinder (for CP or whatever reason can NOT cure itself, right?
 
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Ok
Now I have an additional question :

My local indie BMW shop is running a special on VANOS rebuild ( with anti rattle kit ) and VCG replacement - they're pretty good at what they do, and their special is not bad.
This would be the prefect opportunity for me to get the VCG and the spark plug well gaskets replaced and cleaned I think
As far as VANOS, my car is by most standards too young at 47k miles
But I have heard people post or say that Vanos rebuild is beneficial even at a young mileage and sometimes I have heard a rattle noise but I have no idea is it's Vanos or not ...

What do you guys think ? Should I go ahead and get it done ?
And although it might be again too early should I replace the plugs and / or the coil packs ? It would be easy for them to do as they have remove all that anyway to do the Vanos / VCG
 
Originally Posted By: 97tbird
That is why I am confused. Why isn't the CEL re-lit? And why did it feel ALMOST normal today?
Did you erase the original code before swapping coils?

A misfiring cylinder (for CP or whatever reason can NOT cure itself, right?


Yeah, I cleared the codes before swapping coils. As for things that cure themselves, in my experience, they come back.
 
Often times a leaking sparkplug tube seal will deteriorate a plug boot and cause it to leak spark. This will cause a miss and a code.

Replace valve cover gasket(s), plugs, and coil/boots as necessary.
 
but the code was NOT from THAT cylinder where the boot was bad.

Misfire code was from Cyl #2 and bad boot is from Cyl #1. (Cyl 2 coil pack and boot looked fine)

(this cyl #1 boot thing was accidentally discovered while practicing to pull off Coil packs)


Timely happening perhaps?:
My local indie BMW shop is running a special on VANOS rebuild ( with anti rattle kit ) and VCG replacement - they're pretty good at what they do, and their special is not bad.
This would be the prefect opportunity for me to get the VCG and the spark plug well gaskets replaced and cleaned I think
As far as VANOS, my car is by most standards too young at 47k miles
But I have heard people post or say that Vanos rebuild is beneficial even at a young mileage and sometimes I have heard a rattle noise but I have no idea is it's Vanos or not ...

What do you guys think ? Should I go ahead and get it done ?
And although it might be again too early should I replace the plugs and / or the coil packs ? It would be easy for them to do as they have remove all that anyway to do the Vanos / VCG
 
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^^^^^ if you really like the car & plan on keeping it, no reason not to have it all done, and several problems addressed at the same time
 
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