I have a 2002 Maxima automatic. I have code P1800, I also have P0021, P0139 and P1147. The car does feel rather sluggish when accelerating hard. I can hear what sounds like a clicking noise that fluctuates with RPM and I can describe it similar to if you power up a relay but are barely touching it so the contact inside the relay kind of ''flutters'' that's what it sounds like. This noise happens at lower RPMs because I notice it at around 45mph. I also haven't heard it in a while either.

I checked the VIAS solenoid today for function by applying 12v to the solenoid and I could watch the arm on the power valve operate. Can I assume that that system is functioning properly if the arm moves when power is applied? What is on the other side of the plate the power valve is connected to? Is it possible the arm moves on the outside but doesn't move anything on the inside? I'm kind of at a loss on where to check next. And I do not wish to be raped at the dealership.

Thanks for any help or guidance you can provide

 

I have 02 manual. I have had P1800 come and go over time. It is a code for the solenoid. Check the harness to make sure it is clean and it is plugged snug on there.

 

p1800: vias control solenoid valve:
solution: check the harness connector
: clean the solenoid valve/ replace it
POO21: IVT control
solution: clean both camshaft position sensor
one near the radiator and one near the firewall
(both with green tab)
How to disconnect? press the green tab to unlock and pull the whole connector
Clean crankshaft position sensor
If code persisted: replace both camshaft position sensor with OEM GENUINE NISSAN PARTS

P0139 & P1147:
Bank 1 rear Sensor (02 sensor with white wire)
How to fix: you have 3 options
1. Replace the precat near the radiator and near the firewall which is expensive. (OEM: $599.00 parts only Aftermarket:$299.00)
2. Install headers with o2 sim or nonfouler
3. Cheapest way, gut both precat and install non fouler to the two secondary 02 sensor

 

Did some more looking at the car today. It appears the vias is working appropriately. Valve moves around 1800rpm and goes off around 3600rpm per the tach on the dash. Everything is connected and on tight. I also checked on my bank 1 sensor 2 on my new ob2 bluetooth scanner and the voltage for that sensor does not fluctuate like the other sensors do it just holds a steady .2 volts. So I'm going to assume that one is dead.

Could the vias and ivt codes be caused by the maf like stated in this thread?

https://maxima.org/forums/5th-genera...ml#post8495281

 

Absolutely. Bad MAF can cause a lot of problems; sometimes it throws a code, and other times it does not. I have a 5-gen so I don't have personal experience with 5gen vs.5.5Gen MAF compatibility. However, it seems like you don't have much to lose if you follow the advice from post #9 on that thread. You can get an OEM MAF for the 5-gen for about $87 from http://www.courtesyparts.com/22680-m...-p-193638.html .

 

So I cleaned both ivt solenoids yesterday, they didn't seem to gummed up with anything and tested them with 12V. They clicked pretty ok I guess, not sure how far they're suppose to move inside their housing though. I completed an oil change today, the car was a little low on oil so maybe that's why I was getting the p0021 code. Maybe there wasn't enough pressure to get them to move effectively. I also took the maf apart and cleaned it.

I re read the codes today after I deleted them yesterday and p1800 is already back and the car hasn't been on for more than maybe 10mins of actual run time. So far I've checked actual function of the valve. It opens right around 2000rpm per the dash so depending on how accurate that is it should be right where its suppose to open. I've checked to make sure the connecter is getting 12V and it is. The valve opens and closes so I can assume there are no cracks or breaks or clogs in the lines.

Anyone got any ideas on what could be causing this thing to return so quickly.

 

Out of curiosity, how did you check your VIAS controller?
How can you tell if the Value is closing at 3600rpm?
What makes you think its not the VIAS?

Does the car spit and sputter when sitting at a light?

 

By controller do you mean the solenoid? If yes then I have followed the FSM for the test procedure.

As far as it closing, I have someone standing watching the power valve and I'm slowly reving the engine. It moves at 1800rpm and then moves again at 3600rpm.

I have a code for p1800 which is for the vias but its passed all the checks so far.

And no the car doesnt spit and sputter but I can feel a slight shake to the car at idle not sure if that is common for the maxima or not

 

Took the for a longish ride today and P1147 P0021 and p1800 were all back again in pending status.

I think I have the 02 sensor code figured out cuz its voltage isnt moving but I'm kinda at a loss here on the other two other than just replacing the sensors and crossing my fingers

 

Have you checked/cleaned your camshaft and crankshaft position sensors? (that's what P0021 is about).

 

Pulled the cam sensor on the bank that was throwing the code to clean it. Wasnt that dirty on the inside the outside was filthy though. I did notice some slight marks on the sensor where it looks like something rubbed it. So I also checked the harness and it has 12V with the car on also did the resistance test and all pins check out ok on both banks

 

Small update:

Ordered an O2 sim and installed it and the O2 codes are gone. Cleaned the IVT solenoids, did an oil change, and cleaned both cam sensors and the codes for that are gone. The only one that remains is the P1800 code. I'm at a loss as to what to do, just go ahead and replace the solenoid or maybe it could be the maf like in the other thread. I really dont wanna replace a 140 dollar part if it doesnt need replaced then I'm stuck with it.

Also if I delete my Vias and go with the block off plate and the solenoid is bad will I still get a CEL?

 

You should have downloaded the FSM (Factory Service Manual) by now; you can download it from here: http://boredmder.com/FSMs/Nissan/Maxima/2002/ . It tells (page EC-686) you how to diagnose your P1800 code problem. There are only two possible causes: a) Harness connectors - if bad, the solenoid valve circuit might be open or shorted; or b) The VIAS control solenoid valve.

 

I thought I had mentioned I had the FSM in this thread but it looks like I didnt.

I have gone through the Vias diag per the FSM.

The car has passed all the Vias tests I've completed. And I've completed all but the vacuum test on the tank cuz I dont have the equipment to apply vacuum to it and half the passage continuity test since I dont have a way to power it and test passages A and B. But with no power there is continuity between A and C. If it comes on and off like it should between 1800-3600rpm I dont see how it could be a connector or the solenoid.

 

Bump.
Have you figured out what the problem was?
If not, checking out your MAF is a good idea .....

 

I have the same pending p1800 code. Sometimes the vias solenoid does open and sometimes it does not. Sometimes it feels sluggish and sometimes it doesnt.
What could it possibly be?! Have you figured out the problem

 

If there's a code for vias, then the solenoid isn't working right. Get one from a junkyard.

 

^^^^^yes if 1800 keeps popping up, the solenoid is bad. It will continue to pop up until you replace it

 

Will do. Whats a good price to pay for one at the junkyard? I know they are around 100 bucks new.

 

Just walk out with it. It's small. Grab some mafs and crank/cam sensors while you're at it for extra value.

Unless you're flush with cash.. A generic solenoid should be like 5-6 bucks if that.

 

Haha. No problem. 5 finger discounts

 

^^^^Right grab a few of them and dont worry about the prices hehe!