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the v6 is playing up and I think its plugs or coils
tick over is fine but it just feels rough and dosnt sound happy[ but I need it so still driving it]
now changing the plugs on this looks like a big job with taking half the engine to bits and a new inlet manifold gasket needed as well [got to love the French]
so do I buy six plugs and six coil packs[think that will hit the pocket] so I can do the job in one go? or six plugs and hope for the best?
as its a 1998 don't think theres a dinogstic socket.
course I could replace the lot and find its something else

Hi.
Go with the cheapest first : plugs...then coils.

Is engine management light on..if so code read first before buying anything.

There should be a diag port.

You can reuse the manifold gasket (it's steel) (presuming that it's clean and undamaged of course).

The J4 engine uses wasted spark ignition, meaning if a coil has gone there will be 2 cylinders not firing properly. The packs have to be replaced as a unit.

lozz wrote:Hi.
Go with the cheapest first : plugs...then coils.

Is engine management light on..if so code read first before buying anything.

no light on

'You might be best just to treat the old girl to a ' service.
Plugs'..fuel filter etc...

' fingers crossed 4 ya it isn't the coilpacks... Thems the expensive bits

I've never done any coil packs or replaced plugs on the V6 but if you can get at the coil pack connectors take off the wiring connectors one at a time then start the car...you are looking for the situation where a coil pack (or pair of coil packs, as Jon says) disconnected makes no difference to the running...this (these) packs are the faulty ones.....this goes for faulty plugs as well.
If you can't get at the coil pack connectors then take out every spark plug and check the colour of the electrode... you are looking for any plugs that look a lot dirtier (black usually or soaked in fuel) than the others.
My other method of checking coil packs is to swap them round and see if the problem transfers itself to the other cylinder(s).

well thinking about it iam sure the chap I bought it off said the plugs had been changed recently but if its comeing off then I will change them but theres lots out there from platinum to ngk etc any thoughts on what to use

jonsowman wrote:There should be a diag port.

You can reuse the manifold gasket (it's steel) (presuming that it's clean and undamaged of course).

The J4 engine uses wasted spark ignition, meaning if a coil has gone there will be 2 cylinders not firing properly. The packs have to be replaced as a unit.

Does it use an ht lead to get from the coil to the other plug?

OllieNZ wrote:

jonsowman wrote:There should be a diag port.

You can reuse the manifold gasket (it's steel) (presuming that it's clean and undamaged of course).

The J4 engine uses wasted spark ignition, meaning if a coil has gone there will be 2 cylinders not firing properly. The packs have to be replaced as a unit.

Does it use an ht lead to get from the coil to the other plug?

don't know till I take the manifold off as you cant see anything.

omega wrote:well thinking about it iam sure the chap I bought it off said the plugs had been changed recently but if its comeing off then I will change them but theres lots out there from platinum to ngk etc any thoughts on what to use

NGK, always!

D8 V6's use a single coil pack on the front bank, the rear bank is tee'd off of the front bank with HT leads, I;d go with the plugs first and rear HT lead set as it saves removing the inlet again, the Front coil pack is dead simple to change and if you need one I have one off my old one which is or was OK

Only the D9 uses single coil packs but the Diag will bring up which one has failed

It could be ht lead leakage, not the easiest thing to diagnose but if they haven't been changed before it may be a good place to start.

well ive started all of a sudden I relised that 3 of the spark plugs are under the plastic cover that says v6.so a few nuts and bolts removed and 3 new spark plugs fitted,the ones that came out are pug spark plugs so maybe orginals? they are twin ended and the ngk ones only have single ends? well it seams to run a little better or maybe its just wishfull thinking but its still not right.so will have to do the rear ones and these are coilpacks not singles.
why do they sell plugs for a v6 in packs of 4s?
also left the cover off and ran it at night so I could see if there was any shorting out and there wasn't.
so really need to do the rear but Iam just finding it hard to find the time and I need the car so at the moment iam driving round the fault.

The ones that I've had issues with both shorted out down inside the plug well. Can you get your hands on an ht lead tester?