Volvo 5.0Gi (2001) being sent too much fuel and vacuum pressure low

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Sep 2, 2015
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had a mobile mechanic give me a idea of my engine condition. I tune in the spring and the plugs were pretty oily. Compression good 170-180 all cylinders. His lapttop showed it was sent higher fuel when cold but continued to do so. So, as it warmed it died because it started to flood. His notes say “idle maxed out and vacuum pressure low.” Any thoughts? I’m guessing the oily plugs are aging valve seals. Runs great when I use it, poor when it sits.
498 hours
TBI
 

alldodge

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If your compression gauge is accurate, then its pumping a lot of oil. Compression should be closer to the 150 range. Could verify with another gauge, but if there all in the high range then I would look into having a valve job done.

Your vacuum pressure low could be from a MAP sensor with problems. The MAP (maybe be TMAP) along with ECM controls the amount of fuel.

Where there any codes found by the mechanic?
 

wrench 3

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If it's maxing out the IAC and not gaining RPM the MAP will go low. Did he mention if the CTS (coolant temperature sensor) was reading OK.
 
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No codes. What is involved with a valve job? Is that essentially the top end being rebuilt? I was wondering about the coolant part. It only comes up to about 140degrees. Should be a 160 thermostat. Would that send all that fuel? I’ll check the MAP sensor.
 

alldodge

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Yes valve job is a head rebuild. Many can get away with just grinding the valves and seats, then install new valve seals. To put back together need head and intake gaskets.

The thermostat should be a 160, just remove it and see what its marked for
 

wrench 3

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140* wouldn't effect fuel delivery providing that the computer knows that it's running at 140.
 

QBhoy

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What’s the oil like ? Have a smell at it. Is there fuel in the oil ?
 
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