1997 Subaru Outback rough idle

1997 SUBARU OUTBACK
185,000 MILES • 4 CYL • AWD • AUTOMATIC
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ALASKABRUCE
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My 97 outback 2.5 has been exhibiting rough idle for almost a year now. It starts fine, runs well otherwise, plenty of power, and is getting mid-20's mpg. No oil burning, 165-170 compression on all cylinders, good consistent vacuum readings. Have replaced plugs, wires, coil. Codes show misfire on #1 & 2 cyls. I have also recently replaced the fuel pump, and tried swapping injectors around, but the rough idle remains. Not sure what else to look for. Thanks for any suggestions!
Jul 25, 2010 at 5:36 PM
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MHPAUTOS
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Hi there,

Thank you for the donation,

I would next be checking for a vacuum leak around those cylinders, i do see that you say the vacuum readings are ok, but i still would try a tin of starter fluid and just spray a little around the manifold at those cylinders, if a small leak is there, the revs will increase, try this next.

mark (mhpautos)
Jul 25, 2010 at 7:17 PM
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ALASKABRUCE
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Forgot to mention it but that was also one of the first things I tried, no apparent vacuum leaks anywhere, even checked all lines for possible cracks/splits that would be opening up once engine warmed up, etc.
Jul 25, 2010 at 8:01 PM
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MHPAUTOS
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OK, i will give it some thought and i will get back to you soon.

mark (mhpautos)
Jul 25, 2010 at 8:09 PM