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Mike, Subaru Mechanic
Category: Subaru
Satisfied Customers: 39198
Experience:  Tech Expert
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Engine light on. Only running on 4-5 cylinders below 3000 revs!

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Engine light on. Only running on 4-5 cylinders below 3000 revs! Suspect coil pack on one bank?
Hello and Welcome..
My name is ***** ***** Im happy to help / advise.
Can you give me some more detail / background on this.. what you have checked / done so far etc -
Rgds, MIKE....................
Customer: replied 2 years ago.
Only the lambda sensors, plugs and leads. My garage didn't have a computer that could read all the fault codes!
Hello again Rob -
Im afraid the garage are guessing somewhat here then - and at your expense.
If you suspect the coil pack, then the simplest thing is to swap the coils about ( I don't have enough detail on your model -and worse, 06 is a change year where the coil types changed ) but its either swap them about on the engine - or try another if its the coil pack / block type from another vehicle / replacement if you can..
This is working without fault codes you say - and without codes, thats pretty much all you can do - but its an expansive way.
Honestly - other than the above, the best advice is to locate a garage where you can at least get the fault codes read - anyone can do the work after that - but you do need the fault codes Rob - else this could run into costing you a lot of wasted money.
If after getting the codes you need more help by all means ask me - but most code readers these days give you the code - and the definition for it so its an easy fix.
Do bear in mind though that whatever code you get - it doesn't necessarily mean the "component" at fault.. always check the wiring / circuit - that the code identifies first..
So thats the way forward on this one Rob - While I could suggest other things that can cause a misfire - I would check the coil if you can as above.. Then too - if the coil appears to actually work - you could have a compression test done next - before codes - to check for any mechanical issues with the engine.. for example - a bad valve seat etc will cause a misfire through low or erratic compression -
BUt other than that you MUST have the code read done Rob on this one...if you are still struggling at that point -
Let me know how you go..and / or let me know if you need anything further on this..
~~~~ Meantime - Please do click on the "Exc / Ok rating" for me at this time.. "Thank you" in advance for that .
.. Note that you can get back to me anytime at all after doing the rating - it doesn't close you out --
Best Rgds, MIKE.
Customer: replied 2 years ago.
Thanks Mike don't think it's mechanical because she actually runs ok above 3000revs. It sits at 85mph all day in 4th! Garage mentioned overfulling the cylinders that run lumpy at tick over -3000rpm
Will get it checked into a Subaru specialist ASAP to look at codes!
Hello again Rob -
Im just checking back with you , see how you are getting on and / or if you need anything more on this - By all means let me know , Im always happy to help further if I can at all.. or - if we are done at least for now.. please do click on the OK / Exc ratings for me at this point Rob as thats how justanswer credit me for my time etc.. - "Thank you" ...and again.. you can get back to me anytime as / if needed..
Thank you again -
Best Rgds Rob - MIKE.
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