Vacuum test 5.0gi

mklearl

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Where do I connect the vacuum gauge on a 1998 5.0gipbycce tbi. I can't figure out which hose goes to the pcc valve. There is a large hose from the valve cover to the flame arrestor. There is a smaller 3/8 hose on the other valve cover going to the throttle body just below the throttle cable. See attached photos. Thanks
 

mklearl

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Sorry... the pictures are too big. Anyway the manual states to install a vacuum gauge to a good intake manifold sours. Any recommendations and location?
 

alldodge

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I'm not a VP guy and was hoping with my posting another would come in to help. I'll do some more looking but need to know the year so I can look the motor up
 

alldodge

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Might need the whole engine number to verify, but if your motor is an EFI then there "might" be a vacuum line going from the fuel pump to the intake. If this is the case you should be able to put Tee fitting in the line and read vacuum
 

ericga

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The PCV is on the valve cover that doesn't have the filler cap (#9 in the picture). #20 is the breather elbow located at the same location on the other valve cover. Use the PCV port to take the readings.
 

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mklearl

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Might need the whole engine number to verify, but if your motor is an EFI then there "might" be a vacuum line going from the fuel pump to the intake. If this is the case you should be able to put Tee fitting in the line and read vacuum

1998 volvo penta 5.0gipbycce. There is no line from either pump to the intake I don't think. There is a line from the valve cover to the vst Looking on the schematics there is a plug on the intake.... could I plug into that?I was thinking I had to t into a hose but I'd rather not as the gauge is all 1/4" fittings and the smallest hose off the intake is 3/8. Thanks... I don't know why this is so difficult!
 

mklearl

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The PCV is on the valve cover that doesn't have the filler cap (#9 in the picture). #20 is the breather elbow located at the same location on the other valve cover. Use the PCV port to take the readings.

OK. I thought so. My 2 pics were of the breather hose on the sane cover as the filler cap. The other cover has the pcv valve with a hose to the throttle body just under the throttle cable. Do I t the hose or can I just tap into one of those fittings on a hose end?
 

alldodge

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Wow in your first post you listed the engine and year and I missed it again :facepalm:
Looks like eric has you covered
 

ericga

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Remove the PCV and connect the gauge in the grommet. Make sure you have a good seal or reading will not be accurate.
 

mklearl

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The pcv just lays in that grommet. If I put it in there there is no suction... the suction comes from the other end. I took a video which I will post here as well as in my other post trying to isolate a loss in rpm. I think I did this right.
https://youtu.be/qTeYUXUX5Y8
 

alldodge

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Yes, vacuum comes from the intake side, not the valve cover side.

What kind of RPM loss are you having, WOT or cruise?
 
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