Proper way to install vacuum pump?

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Jan 14, 2017
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I have a 2019 Malibu that is sitting at 80500 miles. I've decided to do some preventative maintenence and replace the vacuum pump before it becomes a bigger problem.

My question being, is one of the bolts torque to yield, because it came with one bolt and the other two holes didn't.

Thanks in advance.

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Should be 3 same sized bolts that hold it on and I believe they're only torqued to single digit foot/pounds. Very little. There's a bunch of decent YT videos on the process. It's an easy DIY job. Make sure you got the jaws in the coupling lined up with the notch in the exhaust cam, wiggle it around so the dowel pins fall into place, then run the bolts down in. Make sure the gasket mating surface is clean. You might want to replace the seal in the head that the coupling runs through as well.

I think it's wise to swap out the vac pump on an LFY 1.5T at this mileage for sure.
 
Is it a problem now, or purely preventative maintenance?

Do these provide vacuum to the brakes? What's the benefit...not having to tap the intake vacuum?

When the pump goes bad it can take the whole motor with it. And I've had a briefly stiff brake pedal on a few occasions.
 
Is it a problem now, or purely preventative maintenance?

Do these provide vacuum to the brakes? What's the benefit...not having to tap the intake vacuum?
Being a small GDI turbo 1.5L, there isn't enough manifold vacuum to support the brake booster, so this exhaust cam driven vacuum pump is unfortunately needed. As @R18Civic mentioned, if the twirly bits inside these vacuum pumps come loose causing it to lock up, the pump coupling can break the end off the exhaust cam. Most commonly what happens when these vac pumps lock up is, the broken bits of coupling land on top of the cyl heads, cause the reluctor wheel pressed onto that end of the cam to move, thus making the ECM think the cam timing is off, when it really isn't. GM went with electronic brake boost in 2023 with the LSD 1.5L, so the LSD version does not have a vacuum pump.
 
Maybe go back o the Stanley Steamer? No more coolant issues, Oil is applied from an oiler can, and you still have the joy of a reciprocating piston and that lovely chugging sound.! And Top Tier? Becomes Top Tier anthracite coal or certified wood. Or maybe even distilled water! And like electric....full torque at zero RPM.
 
Is it the updated pump with no screen on the oil port ? That seems to be what GM has done to improve the life of them since most folks are not oil change savvy.
 
Is it the updated pump with no screen on the oil port ? That seems to be what GM has done to improve the life of them since most folks are not oil change savvy.
Yes it is, all I can see in the way of the screen is an orifice that has a small hex plug in the place of the screen.
 
Is it the updated pump with no screen on the oil port ? That seems to be what GM has done to improve the life of them since most folks are not oil change savvy.
Yeah, these modern cars and their multi speed transmissions need frequent maintenance. I change my oil every 3-3,500 miles and transmission fluid about every 25,000 miles on average.
 
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