MCX Trouble Shooting

[sledskiing]

Need some help here.

I have an Nytro MTX with and MCX turbo. Sled run flawlessly last season. Added a bunch of goodies over the summer and it seems i got some electrical issues. Sometimes the sled runs fine and some times it runs like the MCX box is unplugged. Here is what i've tried

- Dielectric grease in various different connection.
- Red Power wire is fine
- Black ground is fine
- Yellow wire on brake side is fine
- Orange (i think it's orange) on throttle side is fine
- Blue and Brown are not connect - Running a manual boost controller
- Red and Black (that go into the back of the intercooler) wire are fine up to the black connection plug

I have not pulled the intercooler yet.

No air leaks

What else?

At the start of the day the sled runs fine for about 45 minutes and than it starts acting up. When it's not running well here is what happens. At 1/4 throttle it makes 4-6 lbs of boost than completely dies. MY AF goes WAY lean. I let off on the throttle or flare it and the AF goes back to normal. When the sled is running fine the AF is normal. When it starts acting up it is completely unpredictable on and off.

Any help would be great. You can only check / wiggle wires so much before you start loosing your mind.

Ohh I've also tried securing the wire plug into the MCX box better and that only seemed to work for 5 min.

 

[slymax]

Make sure the hose from the MCX box is running downhill. If there is no water in the lines try a can of fuel injection cleaner in the gas. Get some good quality stuff from an auto repair shop that says on the can that it removes moisture. It sounds like the extra injectors aren't firing intermittently, check the connectors and fuel lines for pinching. if your controller has ingested moisture it could be not firing the injectors.

 

[supraturbo]

if at 1/4 throttle it is fine than opening the throttle is become lean then obviousely, your fuel box is not dumping fuel on boost so your map sensor is not reading any boost.......probably moisture in hoses freezing or map sensor frozen.....99% your map sensor is freezing or moisture in hoses freezing out.

 

[DS]

Any small leak or blockage in the lines to the MCX box can cause simptoms like this. I just chased my own tail for several hours on my Phazer.
I found the hose leading to my boost guage with small cracks in it.
Problem solved parts $0.30
Labour 8Hrs - glad I did it myself......

 

[sledskiing]

if at 1/4 throttle it is fine than opening the throttle is become lean then obviousely, your fuel box is not dumping fuel on boost so your map sensor is not reading any boost.......probably moisture in hoses freezing or map sensor frozen.....99% your map sensor is freezing or moisture in hoses freezing out.

moisture and freezing may make sense. cuz it runs fine at the beginning of the day and after the sled sits for a while.

 

[supraturbo]

if at 1/4 throttle it is fine than opening the throttle is become lean then obviousely, your fuel box is not dumping fuel on boost so your map sensor is not reading any boost.......probably moisture in hoses freezing or map sensor frozen.....99% your map sensor is freezing or moisture in hoses freezing out.

moisture and freezing may make sense. cuz it runs fine at the beginning of the day and after the sled sits for a while.

On my impulse kit, i re located the map sensor close to the turbo so it won't freeze....it happen to me several times(frozen map sensor) the one located in the nose of the sled close to stock ecu was the problem for me.i sealed the front headlight, installed prefilter paper on grills ect...but still ingest a ton of snow (off trail ride) so make sure you move from the nose all hoses and map sensors.
solved the problem for me.

 

[mountain_mod_viper]

Mine started to run funny too. It ran good at the truck, poor at 8500' elevation, then pretty good again at the truck. I found a pretty big crack in the exhaust manifold where the 3 tubes are welded into 1 tube. I'm pretty sure this was causing my problem and is something you should check as well.

 

[sledskiing]

Mine started to run funny too. It ran good at the truck, poor at 8500' elevation, then pretty good again at the truck. I found a pretty big crack in the exhaust manifold where the 3 tubes are welded into 1 tube. I'm pretty sure this was causing my problem and is something you should check as well.

hmmm... never thought of that


checked and rechecked all wires and tubes... i'll get er on the snow tomorrow for some testing.