Zex nmu

[DD2013 5.0]

Is anyone really familiar with the zex nmu/tps box? I have everything mounted and wired. I've had the kit working in the past but today it's giving me fits. I unhooked everything to clean up the installed. Today I turned the system on and checked the WOT operation and make sure the box was still programmed correctly. I hooked up the bottle and hit the peddle (with the nozzle unhooked of course) and it fired for a second and quit? I didn't have the fuel line hooked up. Do I need to hook the fuel line up? Before the noids would click any time the peddle was on the floor (no fuel or n2o hooked up) but not it will only click one time and stop. I have to cycle power to the box to get it to click again. I have the tps resistor wire on the brown "falling" voltage tb wire. If I arm the system with the key OFF the noids click rite away
Anyone familiar with these POS ? I'm about to crack it open and wire direct to the coils and just run a micro under the peddle w/ my window switch!

 

[S197OnSpray]

The Zex unit cannot read the falling voltage wire correctly or consistently. The resistor is there to keep the check engine light off. The Zex nmu can read the rising voltage fine but you'll be activating at about half throttle. Check to make sure the resistor hasn't broken, very common from them. Zex makes half ass junk, you would be better off buying an NOS programmable switch and using it to fire off the solenoids. You do not need any lines hooked up to test the system, the Zex nmu will light up different colors in different sequences depending on if it is armed or activated. The manual should tell you which to look for. I can help you set up a different brand tps switch if you go that route. If you stay with the Zex unit, you're in for a lot of headaches down the road, sometimes they work and sometimes they are just finicky.

Good luck

 

[DD2013 5.0]

Yeah it worked fine before. I had it programmed on the falling voltage and it would hit (click) with the peddle rite on the floor. The zex instructions are garbage! Your rite about the rising voltage wire. I it would fire way to early on this wire. I switched it to the brown and it worked fine. When I re program the box it will fire once when the peddle hits the floor then stop and not work again. I'm about to crack this thing open and wire directly to the noids thro a micro under the peddle along with a WS and relay

 

[mantis118]

I've had a lot of zex products over the years. Never had an issue.

 

[DD2013 5.0]

Ok. For those that have had zex products in the past? Can you tell me why the box will only operate on the brown "falling" wire?
I soldiered in a new resistor and cleaned up the install a bit. The box won't click from in side the car but if I pull the cai tube off and run the tb blade by hand the box clicks rite at/before WOT? It does it every time like clock work but will not function correctly from inside the car via the peddle??? I just ordered a wot switch and am going to run the white signal wire threw it. Ill program the box to come on early. This way it can only activate at WOT. Hopefully there's enough e voltage to carry the current threw the extra length of wire?
Or I can swap back to the green/violet wire on the tb harness then run threw the WOT switch at the peddle. Everyone says I should be only the green/violet "rising" but the box acts like it wants to activate on the lower 0.8-1.2 vdc instead of the 3.6-4.2? It's bass actwards for some reason?? It worked flawlessly on a buddies 2011 5.0. The only things that have changed are the tunes and switching from his car to mine

 

[mantis118]

Sounds like bit needs to be reprogrammed. Remember throttle body does not move if the engine isn't running

 

[DD2013 5.0]

Throttle body doesn't move? I can hear the motor on the TB when steeping on the peddle w/ the key on and engine off.
Also on another note any time I flash the car (change tunes) the throttle blade will open and close one the download is complete. The only thing I have solid info on is the voltage per throttle position.
Say I open the blade to 3/4's position. The voltage will be about 3.6. (This is on the raising voltage wire obviously). Then close it and open it again to 3/4's position. Now the voltage will be 4.0-4.2. I did this 10 times. Of those 10 times it was only consistent 2 times. Most of the time showing WOT voltage at 1/2-3/4 throttle position. There has to be a better way? This is a shady set up to say the least?! Even tapping into the TB you DO NOT want to hit the rev limiter or have the TC/AT/SC on or bad things will happen to the intake. Why not just run a window switch with a WOT switch under the peddle and call it a day?

 

[DD2013 5.0]

The throttle blade on my car moves when pressing the peddle with the key on and engine off. I have a vid but I can't post attachments yet

 

[mantis118]

Thats strange. Mine doesn't.

 

[DD2013 5.0]

Since I can't seem to get it dialed in just rite could I run the signal (tps) wire thro a switch under the peddle and just program the box to come on at day half throttle? I think a switch and bracket are 11$ from NO? Or run my arming switch threw the switch under the peddle? I thought breaking the contact on the white (tps) wire instead of cycling main power to the box. Same thing with the relay and the WS

 

[DD2013 5.0]

I have the box clicking rite when the peddle hits the floor. But I'm tapped on the brown (falling) wire. I'm hoping nothing changes when the car is actually running. Tho only issue I see at the moment is if I arm the system with the key off the box clicks. Just need to make sure the arming switch stays off. The box acts like it wants at or near 0-1vdc to activate? I thought these zex boxes activated closer to 4vdc?