My car: 97 Maxima 5-speed, CAI and custom exhaust.... plainly put... stock.

New Mod: MEVI

MEVI Setup: Summit racing RPM switch, Gm solenoid, What appears to be a closed relay and the basic vacuum canister and hoses.

Briefing: the install of the VI couldn't have gone any better. The gaskets fit in perfectly, the bolts all went back in.

Basics of the install.
Vacuum lines: T-fitting T'd into line running from the FPR. The T'd line runs into the vacuum canister. The canister line going out runs into one of the solenoid ports. Another vacuum line runs from one of the solenoid ports to the VI butterfly switch.
RPM switch: Red wire tapped into the positive of cig lighter. black wire tapped into ground wire. white wire tapped into rpm signal (white/green wire). grey wire runs to the relay.
Relay has 5 poles, 85,86,87,87a,30.
85 had the rpm swith white wire, 86 had a wire that was tapped into the rpm red wire (which also has the solenoid pos. wire connected), 87 was the solenoid black wire, and 30 has the a wire that is tapped into the ground wire of the cig lighter.

Problem: One vacuum line and THE WIRING!!!!!!!!!!!!!!!
-The vacuum remains activated whenever the car is started up. (the butterflies remain open). Once i shut off the car, the butterflies stay in the open position until i relieve the pressure by unplugging the vacuum line.

Wierd things that have happened:
-I unplugged the positive and negative of the solenoid away from the power source (cig lighter wires) and left the solenoid alone with the vacuum lines still attached. THE BUTTERFLIES ARE STILL ACTIVATED ONCE I START UP THE CAR!!!

-My Turn signals no longer work.... I will be checking the hazard relay later today to make sure it didn't blow. The fuse is not blown.

Things I've tried/checked:
-I've tried switching the lines around on the solenoid already. The result: either there's vacuum or else there's nothing (one way, the butterflies stay open all the time, the other, the butterflies NEVER open up).
-vacuum canister, looks like it's been hooked up perfectly fine so i didn't touch it.
-The power source (cig lighter) has the proper voltage running through it.

Assessment so far:
-the vacuum lines are hooked up perfectly fine.
-the solenoid is not activating, could be a bad solenoid.
-the rpm switch is not working, could be a bad switch.
-I could have tapped the wrong wire thinking it was the rpm signal (it IS the green/white right?)
-the relay was hooked up wrong. Zack (seller of the MEVI) is helping me out with that and is nice enough to be sending me a relay with the wires already hooked up. What a great seller he is.

PLEASE HELP ME! I DON'T KNOW WHAT IS GOING ON! IF ANYONE HAS HAD A PROBLEM SIMILAR TO THIS OR KNOW HOW TO WIRE UP THE MEVI PLEASE RESPOND! IF YOU REALLY CAN HELP ME PLEASE E-MAIL ME A T LORCH01@GO.METROSTATE.EDU. THANK YOU

 

Come on guys help me out! I'll check back on in a couple hours, i'm gonna go take a look at my car now and hopefully figure something out.

 

On this VSS, whats the part number?
Does it have a little foam filter on it?
I had the same issue.
I ended up removing the foam filter and using that post and left the one on the other side open.


Also, with the Summit switch, why are you using a relay?

 

Ditch the relay first of all, it's a totally unneccesary complication.

Second, if the mevi is open when your car is idling, your vacuum lines are backwards. Mevi should only see vacuum when above the specified RPM and causes the solenoid to open. If it is seeing vacuum any other time, then your vac setup is wrong.

So, switch the vacuum lines around first. That takes care of the "mevi always open" problem. Next you need to tackle the "mevi never opens problem". That leaves basically 3 possibilities. 1) Bad RPM switch wiring. I don't have my MEVI anymore and haven't for like a year so I can't go look at mine to tell you if yours is set up right, but that you can probably figure out on your own. 2) Bad rpm switch. 3) bad vacuum canister (either cracked, or faulty built in check valve). Vac canister is very easy to test both the check valve and its structural integrity so I'd test that initially. Idle the car for a minute (a few seconds should be sufficient but do it for a minute just to make sure) then shut it off. Pull the vac lines off the canister and see if you can hear air rush (hissing noise obviously). If you get an air rush then you know the canister itself is good. Test the check valve by connecting 2 short lengths of vac hose to each nipple, and blowing or sucking through both hoses. You should be able to blow/suck through one hose, but not the other (if the check valve is working). If you can blow/suck through both hoses, then your check valve is faulty and you should just buy a new one, they are like $.99 at the parts store, and more reliable than the ones built into the canister anyways.

Post back with your results.

EDIT:
Something else just occurred to me after I posted this. I suppose it's POSSIBLE that your solenoid is bad, and THAT is what's causing the MEVI to see vacuum at idle. You can test that by just taking each end of the wires and touching them to the positive and negative terminals on your battery, you should be able to hear/feel it click. If you cant tell it's clicking over then it's messed up. Also test the vacuum routes through it, either hook hoses to it or just blow directly on the nipples. You should be able to blow through 2 of the nipples (the are the vacuum route when there is no power to the solenoid) and the 3rd nipple should not be able to move air.

Another EDIT:
This is how good my $.99 check valve and the Napa canister and my mitsubishi solenoid are... I took my MEVI off my car over a year ago, and I just now unhooked the check valve from the vac canister (it's been sitting in a box in my storage room for a year now) and the vacuum canister still was holding vacuum and I heard the rush of air going in it when I unhooked the valve... 1 year after uninstallation lol.

 

Thanks neal. Choua i sent you a napa check valve so you have one. Could you try this and get back to me