MCX nytro not building boost trouble shooting.

[Tuesday]

Last trip out mid day I lost the ability to build boost. I went through all the basics, I was assuming the charge tube just came off but it did not. BOV was working find, wastegate looks good, no vacuum leaks, no exhaust leaks, main connector was plugged in, Intercooler was fully on.

What I end up finding was the 2 wire that runs to the altitude adjusting piece had rubbed through, tapped it up and bingo building boost again. Later on it was loosing again but I think moisture was working its way in to the "short"
because the boost would come and go.

Later that night I spliced in a new piece of wire and the next day appeared to not be loosing boost. Conditions on last day were crappy so did not really get a great chance to test it.

Does this make sense? Short in that wire causes default to not able to build boost?

8000km, the sensor system has worked perfect and felt no need to change it. I know a lot of people swap them out for a manual controller but mine has worked great.

Thoughts?

 

[M5-]

If the short caused the TCV to remain open and cause the waste gate to be open then yes it makes total sense. Mine rubbed through a couple of weeks ago and it killed the sled, blew the ignition fuse, it was intermittent. I think mine was blowing the fuse on the box side of the circuit where your problem might have been on the ground side. Another thing to check and I've had this happen is to make sure there is no water or a water/oil mix in the boost reference tube going to the MCX box. I've had those freeze up on occasion which will shut down the boost until it melts.

M5

 

[SNAFU]

What do you mean by not building boost? Is it still boosting to your base boost level say 12-14 psi or whatever your waste gate is set to?

If you have a short in the wire, I think the TCV will be open allowing boost pressure right to your waste gate.

Get some spiral wire wrap and put it around the wire all the way from the connection at the MCX box to the TCV valve. This will protect the wire from abrasion. I got it at Princess Auto.

 

[Tuesday]

What do you mean by not building boost? Is it still boosting to your base boost level say 12-14 psi or whatever your waste gate is set to?

If you have a short in the wire, I think the TCV will be open allowing boost pressure right to your waste gate.

Get some spiral wire wrap and put it around the wire all the way from the connection at the MCX box to the TCV valve. This will protect the wire from abrasion. I got it at Princess Auto.

It would build a few pounds boost then dump all the pressure. If you have ever had the charge tube come off it was behaving exactly like that.

I was mostly curious about what people have had happen if that wire has wear on it.

I did not pop a fuse just could not build boost.

Thanks.

I will definitely be redoing the wiring with a full wrap.

 

[Octanee]

what about the blow off valve? could be maybe an issue there?

 

[Moto314]

the same thing happened to me this year, put on a manual and fixed it

 

[Tuesday]

what about the blow off valve? could be maybe an issue there?

BOV is fine.

 

[Tuesday]

the same thing happened to me this year, put on a manual and fixed it

Same symptoms? How many km on sled? Curious why you did not just replace the wiring?

Thanks

 

[M5-]

You are at 8000k seems that's when things seem to start needing a little luvin. Fix the wires and maybe see if you can get another TCV to try or put on a manual controller. I like the TCV but they do go south.

M5

 

[SylvanLaker]

There is nothing wrong with Paul's sled, he just scared to squeeze the throttle...

 

[Moto314]

same symptoms,wire rubbed through at 3000k,went to manual because i dont need 20lbs boost all the time