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Rough running engine - suspect valve issue 850 1994

posted by  KlausC on  Fri Jul 6 11:29 CST 2012
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last visit: Fri Oct 24 10:15 CST 2014
[RELATED]

Do NOT remove the cam cover! It is RTV'd in place and a bear to put back on. The valves are not all closed, it all depends on where the cylinder and cam are in alignment.

Do a compression test with a warm engine only. If one cylinder is down, then add a tablespoon of oil to that cylinder, and, if the compression goes back up it is not the valves.

Because you do not have codes that point to a misfire, pull all 5 spark plugs and look for deposits. Too much fuel would indicate that you are running rich because of a vacuum leak - check all the lines that connect to the intake manifold as well as the plastic vacuum tree itself. The large hose from the idle air control motor to the top of the vacuum tree can get loose or crack.

Rather that pull the injectors and trying to see if there is a good spray pattern, get 2 bottles of Techron cleaner and pour them into your tank full of gas and go for an hours drive.
--
My name is Klaus and I am a V♂lv♂holic






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New Rough running engine - suspect valve issue [850][1994]
posted by  purenergy  on Thu Jul 5 17:11 CST 2012 >


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