Popping , lean , Apex with mcx

[apexexpress]

Bought a 2006 MTX with MCXPRESS @ 12 lbs . 1550 Klms . Did not have chance to test drive.
First ride out was popping ( lean ) on Boost
Installed new AEM AFR gauge , found on 2nd ride = idle - 12.5
WOT = 16 + died out on WOT.
Then idle afr changed and Idles lean now 14.5-15 ( sounds lean ) but as soon as I touch throttle 2000 rpm it runs @ 12.5 ( good)
So I added a fuel pressure gauge ( good ) 40 lbs
checked continuity from ECU to injectors and bench tested injectors for mcx , all good.
Sent Gen 1 ecu out for diagnostic to Prince George Yamaha , came back good
Also had bp sensor tested at same time as ecu. good .
Checked all vac/press. lines for leakage ...seemed good.
Checked all wires coming and going from ECU.
Fuel is new @ 95 octane for testing sled out.
Wondering if anybody has any ideas what to try next ???????? Motor seems sound No smoke , rattles , ticking . Just lean at idle and on boost but runs 12-13 AFR any other throttle position...

Could it be valvetrain issues - stretched timing chain, shims , loose cam gear ????????????????? Help !!!!!!!!

 

[Saskapex]

I have a mcx 260 apex that was doing similar things. I ended up finding that the tps was out of adjustment. You can go in through your pod and look at the position. Should be 100 at wide open throttle and around 12-18 I think at no throttle. Hope this helps!

 

[apexexpress]

Sorry forgot to say I checked the Throttle Position sensor values and were in range . But in stock form. Were 95 wot and 12 at idle . should I adjust ?


I am going to try before my next run doing a full diagnostic threw the yami ecu . Then pump my co values up to .5 or 1.0 and also pumping up my main fuel feed values . will also turn my manual boost adjuster in all the way and test run to see what happens ...

See if it is lean with very low boost and fuel jacked up ....... afr, popping etc... Will post .

 

[Ted Jannetty]

Bought a 2006 MTX with MCXPRESS @ 12 lbs . 1550 Klms . Did not have chance to test drive.
First ride out was popping ( lean ) on Boost
Installed new AEM AFR gauge , found on 2nd ride = idle - 12.5
WOT = 16 + died out on WOT.
Then idle afr changed and Idles lean now 14.5-15 ( sounds lean ) but as soon as I touch throttle 2000 rpm it runs @ 12.5 ( good)
So I added a fuel pressure gauge ( good ) 40 lbs
checked continuity from ECU to injectors and bench tested injectors for mcx , all good.
Sent Gen 1 ecu out for diagnostic to Prince George Yamaha , came back good
Also had bp sensor tested at same time as ecu. good .
Checked all vac/press. lines for leakage ...seemed good.
Checked all wires coming and going from ECU.
Fuel is new @ 95 octane for testing sled out.
Wondering if anybody has any ideas what to try next ???????? Motor seems sound No smoke , rattles , ticking . Just lean at idle and on boost but runs 12-13 AFR any other throttle position...

Could it be valvetrain issues - stretched timing chain, shims , loose cam gear ????????????????? Help !!!!!!!!

What you need to know is what size injectors your running and what the fuel pressure is at WOT needs to be 50 psi at 10 psi boost or 1:1 ratio.
Also How much boost could have a sticky wastegate over boosting.

Ted.

 

[apexexpress]

Thanks for the help , I was running only 10 lbs on my last test , has manual boost control adjuster. Stock injectors with MCX injectors on top. It is a 260 - 320 hp kit , running at 260 now .
Have not checked my fuel pressure @ WOT yet , next test I will .
The gen 1 ecu is not good , They would not even re-map for me . The dealer said it would not work well at 800 ft and colder temps so I have a boondocker turbo ecu coming. So I can adjust .

I believe by the 2 Velcro strips on my risers and the 2 plugged off pressure-vac lines there was one on the sled the guy had removed before selling it to me .
I will give it some fuel now ........

 

[apexexpress]

Well after removal of my intercooler to install sensors for boost and intake air temp for boondocker I discovered the fuel rail being popped off . After assembly of intercooler and boondocker control unit I got a good run of 11 afr @ WOT , runs great . now to do some fine tuning , clutching etc...
Thanks for the help everyone !