[JohnDeere8530]

I have a late 02 2.5 Outback

Recently on start up for first 10mins it was misfiring. I traced this to arcing on the coil pack from plug lead4 to the coil pack itself. A clean up and it has been 100%

All went fine for 2 months, then :-

It is now misfiring at high revs/under load, ie not at tick over as before. The more the load/higher the revs the worse it seems to be

I have checked out the OBD and it has not come up with anything conclusive. Im told it could be :-

MAF - wouldnt show an error

Blocked fuel filter/weak fuel pump starving engine of fuel. Probably show an error though ?

First sensor in cat, ie in front of it ? However diagnostics have checked this and say it is normal. (Back sensor flucterating around 2.4v and front one a fair bit lower at around 0.5v, from memory) As said, Im told this is normal

Anything else that it could be, as said there are no obvious errors


Plugs were changed about 20k miles ago and car done 100k on original leads. However these look to be good

If I were to get a new coil pack off ebay, what other models would fit my car? The impreza ones advertised look identical. Would any 4 cylinder coil pack at around the age of my car fit ?

Thanks in advance

 

[JohnDeere8530]

anyone >>

 

[Healey3000]

I have a late 02 2.5 Outback

Recently on start up for first 10mins it was misfiring. I traced this to arcing on the coil pack from plug lead4 to the coil pack itself. A clean up and it has been 100%

All went fine for 2 months, then :-

It is now misfiring at high revs/under load, ie not at tick over as before. The more the load/higher the revs the worse it seems to be

I have checked out the OBD and it has not come up with anything conclusive. Im told it could be :-

MAF - wouldnt show an error

Blocked fuel filter/weak fuel pump starving engine of fuel. Probably show an error though ?

First sensor in cat, ie in front of it ? However diagnostics have checked this and say it is normal. (Back sensor flucterating around 2.4v and front one a fair bit lower at around 0.5v, from memory) As said, Im told this is normal

Anything else that it could be, as said there are no obvious errors


Plugs were changed about 20k miles ago and car done 100k on original leads. However these look to be good

If I were to get a new coil pack off ebay, what other models would fit my car? The impreza ones advertised look identical. Would any 4 cylinder coil pack at around the age of my car fit ?

Thanks in advance

Hi,

Sorry, I don't really have any pearls of wisdom but my first step would be to replace the coil pack and leads, which I think you plan on doing already. At high loads, the spark needs to be stronger as the flame front does not move as well, which may point to a weak coil.

Coil packs are not arbitrarily swappable between vehicles. A rather important characteristic is the inductance, as that defines the charging time. Using the wrong coil could result in a poor spark, a burnt coil or worse, you can damage the coil driver circuits inside the ECU.

The '02 does not have a MAF sensor as it is a speed-density system, using manifold absolute pressure (MAP).