Topic: Missfire (Read 2596 times)

danzigfan · « **on:** 28 September 2020, 07:27:16 »

Hi guys, got a missfire yesterday evening, I checked the codes first and got 12, 31, 129
I believe I can smell a bit of gasoline from the engine bay.
Spark plugs replaced 30.000 km ago + the shortest coil broke and was replaced at that time.
It's a FL 2.5 V6
Any ideas before I start removing plenum?

danzigfan · « **Reply #1 on:** 28 September 2020, 07:38:27 »

Forget about the codes....I unplugged the EGR to get access to spark plugs. No code present now, missfiring all the time, lack of power is very noticeable

danzigfan · « **Reply #2 on:** 28 September 2020, 08:30:14 »

Got the plunum off, plugwells are dry, no oil in them (vectra cam covers).

Enceladus · « **Reply #3 on:** 28 September 2020, 09:21:36 »

Your symptoms suggest that the coil pack has failed. Was the replacement a genuine Bosch part? Or some other aftermarket brand?

Was the engine running when the crank sensor code appeared.

danzigfan · « **Reply #4 on:** 28 September 2020, 09:32:24 »

Tested the resistance on suspected coil lead and got 4.5 Kohm. So I went to to test a set of new coil leads I still have and got from 5,5 shortetst to 9Kohm being the longest.
Seems fine? 🤨
Coil pack (behind the engine) is still factory one I believe
Spark plug lead is no name brand.
If only I could test which one isn't firing but impossible with plenum on

Nick W · « **Reply #5 on:** 28 September 2020, 09:51:19 »

Quote from: danzigfan on 28 September 2020, 09:32:24

Tested the resistance on suspected coil lead and got 4.5 Kohm. So I went to to test a set of new coil leads I still have and got from 5,5 shortetst to 9Kohm being the longest.
Seems fine? 🤨
Coil pack (behind the engine) is still factory one I believe
Spark plug lead is no name brand.
If only I could test which one isn't firing but impossible with plenum on

Have you considered something like THIS? There are other similar testers, I had one that just touched the plug lead.

danzigfan · « **Reply #6 on:** 28 September 2020, 10:03:27 »

Will be added to the basket soon, but I don't have it now.
And I can't remove bl..y wiper arm to get to the coil pack. I almost forgot how cramped it is behind the engine, omega was running almost flawless for more than 5 years

Enceladus · « **Reply #7 on:** 28 September 2020, 10:04:41 »

There are three coils in the pack and each provides spark to a pair of cylinders at a time. One in each bank. So if one cylinder has weak or no spark then it's pair will be similar. The cylinder pairs are on the forum somewhere. Search for wasted spark.

Nick W · « **Reply #8 on:** 28 September 2020, 10:18:52 »

Quote from: danzigfan on 28 September 2020, 10:03:27

Will be added to the basket soon, but I don't have it now.
And I can't remove bl..y wiper arm to get to the coil pack. I almost forgot how cramped it is behind the engine, omega was running almost flawless for more than 5 years

More MONEY

I have one but have never needed to use it on wiper arms, firm jiggling has always been enough

danzigfan · « **Reply #9 on:** 28 September 2020, 10:30:23 »

I have three of those pullers....it won't budge

danzigfan · « **Reply #10 on:** 28 September 2020, 10:31:00 »

danzigfan · « **Reply #11 on:** 28 September 2020, 10:31:39 »

These are from left bank, all look the same

Nick W · « **Reply #12 on:** 28 September 2020, 10:35:52 »

Quote from: danzigfan on 28 September 2020, 10:31:00

How long have they been fitted, as they're utterly oppsed

And does your scuttle leak? That might explain the brown marks around the insulators.

danzigfan · « **Reply #13 on:** 28 September 2020, 10:40:23 »

They've been in for 20k miles and yes, the scuttle doesn't leak as I sealed it per guide on the forum. Plug wells were dry

Enceladus · « **Reply #14 on:** 28 September 2020, 13:05:45 »

Are some of the sealing washers missing or damaged on those plugs?
If the scuttle was leaking it could have dripped water onto the coil pack. And damaged it.

Try new plugs since they look like they need to be changed. However my guess is the coil pack. If yours is original it must be a record for longevity.

Fold the wiper arms upwards before using the puller. Partially refit the nut to keep the puller central, if needed. That should get the wipers offf.

danzigfan · « **Reply #15 on:** 28 September 2020, 13:15:31 »

I'm allready on my way to buy new plugs. Thanks for all your help

johnnydog · « **Reply #16 on:** 28 September 2020, 15:22:20 »

It is very unusual for more than one plug to fail at the same time. As they all look like they haven't been receiving a spark or firing , I would guess that the problem lies elsewhere, such as the coil pack as has been previously suggested. As you have already removed them, new plugs are the first thing to fit and go on from there to then see how it runs before checking the leads and coil pack.

danzigfan · « **Reply #17 on:** 29 September 2020, 09:21:48 »

Yep....dis pack failed.
My swear jar is full and I believe I deserve a big cup of coffee after pulling this one out

Nick W · « **Reply #18 on:** 29 September 2020, 10:11:37 »

All your pictures, and the problems that you're chasing, seem to be of old parts. As you need new plugs, and coil pack, the only other thing ignition part left is the plug leads. Now would be the time to change those too......

Do the whole job once, and forget about it.

danzigfan · « **Reply #19 on:** 29 September 2020, 10:19:29 »

I'm considering that option yes....as I wanted to drive it trough this winter. This problem just cought me by surprise because I'm already working on my next Miggy....It's a sort of addiction

Enceladus · « **Reply #20 on:** 29 September 2020, 11:24:11 »

There are three possible coil pack designs. The coil pack you need is Bosch part number 0221503017 (GM part #90541062 / Opel Kat 12-08-075). This coil pack matches yours which has the harness plug at the end of the unit in the same orientation as the plug lead pillars. The harness connector has oval ends. This is the most recent design.

You should find the Bosch number and logo embossed onto your old coil pack. And any new replacement.

You can try a GM / Opel dealer and see will they special order a part from Germany, but it will cost more than the car and will still be the same Bosch part. Just make sure that whatever you buy is a genuine Bosch from a Bosch dealer.

danzigfan · « **Reply #21 on:** 29 September 2020, 14:22:36 »

I have 2 coil packs in my garage, they've been there for 5 years 'just in case"...But they have different harness plug so off to the ebay we go. Thanks

danzigfan · « **Reply #22 on:** 01 October 2020, 16:52:25 »

Update:
Got the coil pack today after work, installed it + new spark plugs. All done very fast surprisingly.

It purrs like a kitten again, thanks for all your help

News:

Author Topic: Missfire (Read 2596 times)