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99 2.5 DOCH Plugs foulded bad

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I picked up a 99 Outback 2.5 DOHC.  I ran but no power, I could hardly keep it running. 

The Timing is good,

I pulled the plugs, the back 2 where heavy deposits but white in color

The front 2 had heavy deposits, black as can be.

 

With the new NGK plugs it ran a little better but still lacks power and will not idle.

 

218K on the car, the HG appear to be OK and the oil is good.  Any chance of cleaning this out and making it a good Subaru or should I just drop my 2.2 in it and call it a day?

 

Thanks, Larry

Check it for an intake leak or leaking fuel injector o-rings. Something is making it too rich. Though It seems odd that its front half vs rear half instead of left/right.

 

Were the deposits on the rear plugs kind of a crusty ash? Could be oil fouling due to worn rings.

 

Compression check may be in order.

Edited by Fairtax4me

  • Author

Deposits were hard and very heavy. 

Rear Plugs White and crusty

Front Plugs Black and hard

 

With the mileage at 218K and the fact that it's a DOHC, I think it's time for the 2.2 swap.

  • Author

Subaru and they look good.  I may swap them out with spares when I have time to see if it makes a difference.

 

Thanks for the info.

Larry

Can you post pics of the plugs that came out of it?

I'm thinking oil fouling. More severe in the front two cylinders.

 

Idle could be a separate problem (dirty IAC, clogged PCV valve, vacuum leak)

 

Run it for a while and pull the plugs again.

  • Author

What's your email?

I'll send you a plugs pic.

Larry

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