nismopc

iTrader: (3)

Ok, so my car has been saving random mis-fire codes, small emmissions air leaks as well as P1800 - VIAS Solenoid open loop. My car has also suffered a major loss in power throughout the entire RPM range.

I finally pulled out the FSM last night and performed the non-Consult procedures for the VIAS P1800 code and found out the solenoid is dead. No current passing through. Basically, due to the suction from the IM, the butterfly would basically stay closed throughout the entire RPM range. Suffered from lack of air. So, as a quick fix, I pulled the air line from the upper IM and nippled it off so that the butterfly is open at all times.

So happy. Power is back. So far no codes have been saved.

NOTE: If your solenoid is still working and you do this, I am pretty sure the ECM will begin to save codes and possibly a CEL.

Anyhow, went to dealer to price out new solenoid and they want $190 for it. Dayum! So apparently, I will be keeping the VIAS bypass going forward and might eventually just remove the whole butterfly assembly and replace with a block off plate. Helluva lot cheaper than that!!

Just somewhat of a vent and praise. The VIAS mod does appear to work well so far.

NmexMAX

iTrader: (22)

No, it will not. All signals are fine if you leave the solenoid connected electronically. It has no way of deciphering how much, if any, vacuum exists whenever power is applied to it. So, as long as it's connected electronically, you're fine re: MIL.

Try www.pinnaclenissan.com for some decent prices.


I have dyno proof of this losing a lot of torque. (With assembly kept intact and inside the IM, just in the open position)

nismopc

iTrader: (3)

Thanks. I was also going to try nissanparts.cc I have always had excellent luck, service and pricing with them.


I recall some dyno runs out there regarding this and there are several believers of the VIAS block-off plate mod on the Altima forums @ nissanclub.com, but I recalled it to be a slight loss of low-end torque which is quite odd, because I am actually now slipping the tires on take-off very easily.

Could it possibly be the way your intake is set-up doesnt work well with the VIAS open?. Yours is set-up like this right? Short ram, large MAF, to stock air box? I am running with stock helmholtz, stock MAF, and a conical filter.

You have you dyno online somewhere? Curious to see where the drop in torque is.

NmexMAX

iTrader: (22)

I did that dyno when my only mods were headers and the exact identical intake you described above, so that would shoot that theory down.


Of course.
Look at the red and blue curves (highest on top), semi obvious where the tq loss is @ even though those are HP curves.


Cliffs: Apparently removing the entire valve assembly (i.e. block off plate only) did provide gains vs leaving the assembly in BUT LEAVING IT IN OPEN position.