Does anyone else notice that the RPM moves up and down a little at a stop after installing the Mrev+ and 5/16 Spacer? The change is very little, you can barely see it move but you can feel it. Is the idle supposed to stay still when your at a stop or does it move?

 

Depends on how much it moves. Are you talking 100rpm flucuations or 200+ rpm flucuations. I know prior to the spacer install, my rpms sometimes would bounce around by 100rpms which I think was related to the cooling fans kicking on and off.

If your rpms are bouncing around a lot, consider doing a vacuum test. It should be a rock steady 20 hg at idle on a warm engine. If the vacumm bounces or is below 18 hg, you probably have a very small vacuum leak.

 

How would I do a vacumm check? It moves around 100-200 RPM, it's acutally not that much but I can feel it making the car shake a little when it moves.

 

You'll need a vacuum gauge. I use a MityVac (available at Sears, auto stores) and it costs about $30, but it's worth a lot more to a shadetree mechanic like myself. With it you can check vacuum, put solenoids under vacuum to test their operation during trouble shooting, change out brake fluid by yourself, inject differential fluid, etc.

To test vacuum on the G/Z VQ, simply pop off the rubber nipple cover on the front passenger side of the intake manifold and attach a vacuum line to the nipple and to the gauge and take the reading.

 

Ok, got it. Thanks

 

I looked up MityVac on the Sears website and there are a couple of different ones. Could you tell me which one is the right one. http://www.sears.com/sr/javasr/searc...&vertical=TOOL