# Solenoid Trouble



## joneill1975 (Nov 2, 2005)

2002 I35 has a P1800 code which is for the VIAS solenoid. Can anyone tell me how to troubleshoot the problem and fix it? Does this affect how the car runs?

Thanks in advance.


----------



## smj999smj (Jan 1, 2006)

The VIAS solenoid controls the vacuum flow that operates the power valve inside the intake plenum. The power valve is a set of butterfly valves that control the amount of airflow through the intake runners. So, if the power valve isn't working properly, you will feel a difference in engine performance. Testing will be difficult without a scantool. Some checks are simple. Make sure you are getting power to the VIAS solenoid harness connector red/yellow wire with the key "on." If not, check 15A fuse #20 in the fuse block. The yellow/green wire is the ground circuit which is grounded by the ECM (pin #27). You can unplug the VIAS solenoid and ECM and do a circuit test on that wire for continuity and resistance (should be minimal) and make sure it is not shorted to ground. You can check the vacuum hoses to the VIAS solenoid for leaks, crimps and loose connections. I wouldn't be surprised if the VIAS solenoid, itself, is what the problem is. You can hook up leads between it and a 12 volt battery and see if the solenoid "clicks" as you connect and disconnect the ground. If it doesn't click, the solenoid is stuck and you need to replace it.


----------



## joneill1975 (Nov 2, 2005)

The check engine light came on the other day and now I am getting these codes.

P0455
P1448
P1800

Is this the solenoid causing all of these codes to trigger?


----------



## smj999smj (Jan 1, 2006)

P0455-Evaporative emissions system gross leak
P1448-Evaporative emissions system canister vent control valve
P1800-VIAS control solenoid valve

The EVAP system codes are likely related and could be due to a faulty canister vent control valve. Diagnosing would be needed to confirm. The P1800 code is likely unrelated to the EVAP codes.


----------



## dquestagod (Sep 6, 2014)

*DQUESTAGODMOD P1800 BYPASS*

I had the same codes for my 2002 Nissan Maxima, So this is How I fixed it. I replaced Evaporative emissions system canister vent control valve with new one it's about $70 at Autozone. That cleared P0455 and P1448 codes. But it still had a vacuum leak at the VIAS flap housing. So I bought a VIAS Block Plate Kit from NWP Engineering, Inc - Custom Design and Fabrication - Automotive Performance Specialist for $40 that fixed that problem and gave it better throttle response. Plus eliminates the VIAS control solenoid valve. Now for the pest P1800. If your solenoid is bad and you don't want to spend $170 on EBAY for the part brand new. There is a way to bypass the pest and keep the P1800 clear. It's real simple.The ECU need to see resistance from a solenoid or something similar so I Used a Led light!!!!! GENIUS RIGHT !!! This is called the DQUESTAGODMOD !!! I brought the light from Auto zone for $15 a while back for interior looks. But to my surprise it gave a brighter glow every time i rev the engine.Nice allusion at night. Pilot Automotive - LED Strip Lighting: CZ-3096B 
wired it into red/yellow wire positive and ground the yellow/green wire on the plug. DONE !!! :nerd: 

leave a thanks !! For more mods send me a message.


----------



## dquestagod (Sep 6, 2014)

It's been six days so far no dtc's and passed emissions with flying colors on 9/8/14. It takes around 50 miles to complete. remember to let car coast down from highway speeds with no brakes to 20 mph for it to get the correct reading to ready catalyst test. It's a pain to get that last light off.


----------

