Misfire after plug change

[huesey1974]

Need some help, I changed the plugs on drivers side and started her up and CEL came on and is misfiring, Plugs are defo in proper and im a bit worried. I have changed plugs on loads of cars and are usually very easy but the Porsche not so, Im wondering if the coils are seated properly. Do the screws seat them properly or do they need a good shove in as im thinking maybe the furthest rear coil didn't pop in and was a little proud when I put the screws back in. Any thoughts?
Thanks

 

[infrasilver]

The screws should seat them in theory but that rear one is a bitch to fit again and the electrical connector is a bit awkward, are you sure that is on okay?
I always push the tube part of the coil pack on first with a ratchet extension bar to make sure its in before fitting the coil pack head and I alway lube it very slightly with WD40 before fitting the tube.

Could be coincidence that a coil pack has gone. A CEL doesn't always show with a faulty pack so may be just the connector wire plug.

I was supposed to changing all my spark plugs today but ended up stripping a washing machine down to bare bones, , amazingly the bearing in the washing machine resembles the IMS bearing very closely.

 

[huesey1974]

Hi,

Im going to have another go in the morning, Plugs were defo tightened but I thinking a coil is not seated properly or the electrical connector as I had a problem with one of them. Will let u know.
I have had the joy of stripping a washing machine but when I put it back together it got worse as the motor decided to snap off on full spin lol!!!

Cheers

 

[Clanky]

It could be a duff plug. It does happen occasionally.

Seen it a lot on Jetski's, but generally put it down to higher compression ratios on them.

 

[bobsan]

First guess would be coil pack connector didn't 'click' home correctly. Was it cylinder four (right rearmost) per chance ??

 

[huesey1974]

Hi,
yes it was, Going to go for it now. Will let u know.

 

[maor]

Easiest to buy a cheap android bluetooth reader, it tells you which cylinder has the misfire.

 

[huesey1974]

Right guys,
Stripped it all back down again and al is well, I think the problem was the electrical plug on the EASIEST one wasn't seated properly, The little tab on the coil seems to be missing that the connector snaps over and I couldn't get the rubber boot to slide back so I could see the plug in position. I changed this coil to the middle so I could make sure the connecter was properly in and then I could hear the other one snap on over the connector. I fired her up and sounded much better although with the first couple of revs there was a pop from the exhaust but im thinking un burnt fuel from the short drive yesterday. It cleared after a couple of revs and no CEL. Going to attack the other side now.
Thanks

 

[huesey1974]

Job done!!! Not much skin left on my arms but she's done and feels even better to drive, Not sure if they were the original plugs (Beru) but they looked done anyway, Cleaned all the coils. Noticed 2 of the coils were different part numbers and the seating bolts were harder to get out so think they must be originals too. My exhaust manifolds don't look great right enough so may replace these in the near future. Bone dry underneath regarding oil leaks so that's good.

 

[JohnnyDangerous]

Strangely on Cayennes after the plugs are changed we normally find 1 or more coil packs fail shortly after, not noticed this on 911's/Boxsters though, swapped mine out for Iridiums and run Hi Boost with no problems for 2 months.