Update: EVAP CS purge flow monitor & Knock sensor

[vengeful]

If your gas cap wasn't properly tightened, it would trigger the MIL. It could be as simple as that.

 

Also, you can check the codes by turning the screw on the ECM to Diagnostic Mode 2, and it'll flash the MIL in a pattern and give you the codes. That will also reset it if you turn it back counterclockwise. The procedure is in the FSM.

[QuismO]

If your gas cap wasn't properly tightened, it would trigger the MIL.  It could be as simple as that.

 

Also, you can check the codes by turning the screw on the ECM to Diagnostic Mode 2, and it'll flash the MIL in a pattern and give you the codes.  That will also reset it if you turn it back counterclockwise.  The procedure is in the FSM.

ok so i saw the write up in the garage>how to section for r50's. I should add, that yea that thick clear tape that covers the knob is a pain if you have big hands (i have small hands, and it was already tough for me to move around behind the ECM)...pretty tight under the dash behind the ECM. On top of that, not any straight-slot bit will work, get the smallest one you can, a tiny #4 (i tried a 3/16 straight-slot...didn't fit) straight slot bit was perfect for getting into the slot of that knob.

 

but i messed up...my dumbass didn't bring the printout of EC page 49 from the FSM, so i turned it counterclockwise (or so i thought i did, 'cause i think it's initially in that position), then turned it clockwise. so i resetted it by doing this. i'm going to see if the light turns back on, then i'll pull the DTC if it happens again. so the code i got was 0505...no failure indicated.

Edited October 19, 2006 by QuismO

[vengeful]

Well, drive it around a bit and see if the MIL comes back on. If it doesn't, then you're golden. If it does, get the codes per the proper procedure and don't reset the ECM this time.

[QuismO]

Well, drive it around a bit and see if the MIL comes back on. If it doesn't, then you're golden. If it does, get the codes per the proper procedure and don't reset the ECM this time.

45 miles after the accidental reset...no light yet. but i'm still *crossing fingers*, not quite reassured yet. i've read in the FSM that the same error has to occur on 3 consecutive trips for the MIL/SES light to come on, any minimum distance for these trips required?

 

also, it states in the FSM that various information will be erased, including emissions-related info...will this affect a california smog test? if so, how long/far would it take for data to be recorded and stored? FYI, smog is due before registration renewal in december.

 

any ideas/input welcome...thanks,

ian

 

PS~i sure hope i'm golden venge

[vengeful]

The readiness monitors have to be set in order for it to start receiving data from the sensors. Once those monitors are set, it takes 3 trips for a constant DTC or 1 trip for an intermittent or pending DTC. Only a constant DTC will illuminate the MIL, but certain ones (like the knock sensor) wont.

 

It usually takes a few drive cycles and about 100 miles or so for everything to be set and all the sensors to be reading.

[QuismO]

soo about 100 more miles or so, and the monitors will just START to begin monitoring?

[QuismO]

ok....the light came on...i got the MIL DTC's.

 

0304 and 0111 which when converted to obdii standards, are po325 and p1447 respectively.

 

0304 is the knock sensor and 0111 is the evap purge flow/mon

 

for 0304...looks like i should check/test the connections...if those are good, replace the KS and i should be straight?

 

for evap...looks a little intensive according to the FSM as that one code can mean a variety of things....how "BAD" is this problem? ie. what consequences are there if i keep driving for a little bit (don't have much funds right now)?

[vengeful]

I wouldn't worry about the Knock Sensor, that won't trigger the MIL. That won't really effect the way your vehicle acts at all.

 

1447 will eventually melt your cats, so that's the one you want to take care of first. Here's the screenshot from the FSM of what the possible causes are.

 

 

Check the EC section of your FSM for your proper diagnostic procedure.

[QuismO]

ok after reading the FSM thoroughly, it turns out that my evap purge flow code isn't as big of a problem as i thought...i mean in terms of solving...at least i think so.

 

it turns out, according to the DTC, that the problem most likely lies between the intake manifold and the EVAP control system pressure sensor...which leaves the following parts as possibly no good:

 

1. EVAP canister purge volume control valve

2. EVAP canister purge control solenoid valve, and

3. EVAP canister purge control valve (i believe this is the infamous charcoal canister)

 

here's the roadblock, it CAN be other things in the EVAP system, that can cause the entire EVAP system to fail...also, i don't have the tools necessary to test out the canister (however, it has no cracks, looks immaculate), or the solenoid valve.

 

there is still a little light at the end of the tunnel, thank god. i whipped out the multimeter and started testing out the purge volume control valve (they should really rename these things, easy to lose track on what the hell the fsm is talking about). according to the procedure, i had to test the resistance between

 

terminal 2 and terminals 1&3

and

terminal 5 and terminals 4&6.

 

i was supposed to get a reading of "approximately 30 ohms"

 

so my question is, how approximate is approximate??? i got a reading of about 20 ohms throughout...sounds off to me. can someone verify whether or not this is ok or not on their r50? it only took about 10 minutes to unplug the harness and test the contacts.

 

i know that there are other parts to test, but i don't have pressure gauges or tools that apply pressure, etc...so if 43 ohms is off, hopefully i can start by replacing the purge volume control valve...i wish i had a mityvac test kit or something.

 

 

now for the knock sensor...attached to the engine block eh? what's the easiest way to access this sensor? looks like i'll have to remove the manifold...what do you guys think?

Edited October 21, 2006 by QuismO

[QuismO]

i want to add something about testing out the contacts for the valve...

 

i tested it two ways, as the wording in the FSM is kind of vague:

 

 

the different colors represent 2 different tests (example: the green lines represent the multimeter connected to pins 2 and 3 only, and the blue lines represent the MM connected to only pins 1 and 2.

 

here, i have pins 1 and 3 in parallel, and one lead from the MM connected to pin 2

 

i believe method 2 is the correct method, and i got approx 20 ohms.

 

with method 1, i got 40+ ohms...either way, it's not 30 ohms, but still not sure if -10 ohms is acceptable...still awaiting some input.

Edited October 21, 2006 by QuismO

[XPLORx4]

now for the knock sensor...attached to the engine block eh? what's the easiest way to access this sensor? looks like i'll have to remove the manifold...what do you guys think?

Ignore the knock sensor until you're doing some kind of work that requires the intake manifold to be removed anyway. A KS DTC does not trip the MIL, and its proper operation is not required to pass CA emissions. I've had a KS DTC for at least 2 years, and my CA SMOG test passed last September with this error.

[QuismO]

Ignore the knock sensor until you're doing some kind of work that requires the intake manifold to be removed anyway. A KS DTC does not trip the MIL, and its proper operation is not required to pass CA emissions. I've had a KS DTC for at least 2 years, and my CA SMOG test passed last September with this error.

sweet...that's REALLY reassuring...i just feel the pressure since my smog is due in december =P

 

now all i need is someone to test out their valve for me hehe :help:

[QuismO]

ok i'm in sacramento right now, and i was planning on checking the readings on the EVAP purge/flow valve on my cousin's '98 pathy...but his purge flow valve is different. so i'm asking if there are other '97 (and possibly '96) pathy owners out there that can check for the above readings on their valve for me.

 

Thanks,

ian

[QuismO]

ok i bought the purge valve from nissan for close to $200...OUCH. it's pictured below:

 

i removed the one in the truck...tilted it to the side and little round balls of charcoal started falling out. i tried to get all of it out, but it's still clogged, so i'll just install the new one AFTER i blow out the lines. i'm assuming that this charcoal came from the canister? there is a little black plastic can (located on bottom right corner of the above picture) that i'm wondering about...should i be cleaning or swapping this thing out?

 

also, i'm looking at the vacuum line diagram under the hood, and after following the lines, i can't seem to find the "canister". from the purge canister valve, the line goes from the driver to passenger side along the firewall, then drops down...where exactly is the canister? how much do these things run for? i'm assuming that i have to replace it...correct?

Edited October 23, 2006 by QuismO

[XPLORx4]

Too bad you already bought a new valve. You could have just unscrewed its two halves and gotten out the granules that way.

 

That other little valve can just be shaken out if it's got carbon granules in it. You shouldn't need to replace it.

 

The EVAP canister is located behind the left rear wheel, tucked up under the bumper.

 

There are rubber connection tubes between the hard metal EVAP lines at the canister, above the fuel filter, in the left front wheel well, and in the engine compartment by that other little valve. You'll have to remove all of them in order to blow the EVAP lines out one section at a time. It'll make a big mess everywhere.

Edited October 23, 2006 by XPLORx4

[QuismO]

Too bad you already bought a new valve. You could have just unscrewed its two halves and gotten out the granules that way.

 

That other little valve can just be shaken out if it's got carbon granules in it. You shouldn't need to replace it.

 

The EVAP canister is located behind the left rear wheel, tucked up under the bumper.

 

There are rubber connection tubes between the hard metal EVAP lines at the canister, above the fuel filter, in the left front wheel well, and in the engine compartment by that other little valve. You'll have to remove all of them in order to blow the EVAP lines out one section at a time. It'll make a big mess everywhere.

hehe thanks xplor...i just found an old thread that you posted in about this problem...i PM'd you as you were posting your reply on my thread. how much was the canister and rear purge valve?

 

i think i still need this valve 'cause there is still no flow through it...maybe i need to clean it out more though. hopefully they'll take the part back if i do end up cleaning my original valve and it works fine. but right now...i don't think it'll be good even if the lines are blown clean.

 

i guess all i need to do now is blow the lines, change the canister in the rear, and the rear purge valve, and clean out the little components throughout the system...sound correct? did i leave anything out?

 

EDIT: is the charcoal canister required? i think i read somewhere that someone did away with the canister and didn't see/feel anything different. but i think it was in a wd pathy, and i could be wrong--maybe they were talking about another part. even if it does work without it, is it calif smog legal w/o the canister?

 

ALSO, i think this problem is contributing to my minus 2 or so MPG as the only way for the pressure to be released from the gas tank is through the fuel line and into the engine...possibly forcing more fuel than needed--unless of course the gas cap is opened. does this hypothesis sound good? =P i hope so, i'd love to get better gas mileage hehe

Edited October 23, 2006 by QuismO

[QuismO]

Too bad you already bought a new valve. You could have just unscrewed its two halves and gotten out the granules that way.

 

That other little valve can just be shaken out if it's got carbon granules in it. You shouldn't need to replace it.

 

The EVAP canister is located behind the left rear wheel, tucked up under the bumper.

 

There are rubber connection tubes between the hard metal EVAP lines at the canister, above the fuel filter, in the left front wheel well, and in the engine compartment by that other little valve. You'll have to remove all of them in order to blow the EVAP lines out one section at a time. It'll make a big mess everywhere.

man i wish you posted this earlier =P i cleaned out that purge valve in the engine bay...seems to work nicely now. how much pressure is required to clean out the lines? is an air compressor necessary? how 'bout cans of compressed air (possibly good for only the front lines eh?)?

 

I paid about $210 for that damn valve, hopefully i can exchange it for the canister and the rear purge valve. the receipt says no refunds/exchanges on smog related parts, hopefully they'll make an exception since i didn't even install it.

 

i'll make sure to blow out the lines in the driveway, if i do it in the garage, it'll look like i have rat sh*t everywhere ahahaha.

 

i'll buy some hoses so that i can have some handy...my hoses aren't brittle, but they seem to have "glued" themselves to the metal tubing over time. cutting them off and replacing them will make things easier and quicker.

[XPLORx4]

how much pressure is required to clean out the lines? is an air compressor necessary??

.

.

.

 

i'll buy some hoses so that i can have some handy...my hoses aren't brittle, but they seem to have "glued" themselves to the metal tubing over time. cutting them off and replacing them will make things easier and quicker.

You need an air compressor with about 90psi and one of those little tapered "blow nozzles" to blast those granules out:

 

A can of compressed air (the stuff for computers) won't do the trick.

 

And for getting those hoses broken loose, you don't need to cut them. Use a pair of pliers to grip the hose and twist it. Or, you can insert a small hook or flathead screwdriver between the hose and the metal to help release it.

[QuismO]

You need an air compressor with about 90psi and one of those little tapered "blow nozzles" to blast those granules out:

 

A can of compressed air (the stuff for computers) won't do the trick.

 

And for getting those hoses broken loose, you don't need to cut them. Use a pair of pliers to grip the hose and twist it. Or, you can insert a small hook or flathead screwdriver between the hose and the metal to help release it.

hey, thanks xplor, you've been a great help on this. do you remember how much the purge valve and canister was off the top of your head? do you have any part numbers?

[XPLORx4]

These links might be helpful:

 

http://www.4x4parts.com/ubbthreads/showfla...6&Number=116825

 

http://www.4x4parts.com/ubbthreads/showfla...6&Number=265647

 

http://www.4x4parts.com/ubbthreads/showfla...6&Number=278931

[QuismO]

These links might be helpful:

 

http://www.4x4parts.com/ubbthreads/showfla...6&Number=116825

 

http://www.4x4parts.com/ubbthreads/showfla...6&Number=265647

 

http://www.4x4parts.com/ubbthreads/showfla...6&Number=278931

man those links are EXACTLY what i'm going through!!! the third link, where that guy bought the part for $225 is the one i bought. exact part number. i'm going to try and exchange it for the canister and the valve in the rear. so what i'm guessing is, the valve near the canister is the "vent valve" that venge was talking about in link 2?

 

EDIT: i'm just curious why nobody on this forum has had this problem and documented it...or why it's so hard to find in the search function...i found yours, but man, i was worrying hardcore 'cause i thought i had a freak problem for a while there.

Edited October 24, 2006 by QuismO

[QuismO]

UPDATE: so i went in and exchanged the purge volume control valve for the EVAP canister and purge valve with o-ring...i went on the pinnacle nissan site and looked up the msrp's for the two parts and told them that the other nissan dealer quoted me for those prices and they matched it no problem. $260 for the valve and canister including tax, kind of pricey, but at least i don't have to pay the dealer's quote of $800-1000 for this job.

 

i'm almost done, already disconnected all of the lines and pulled the canister, i'm just waiting for my buddy to get here with his air compressor so that i can blow the carbon bits out of the lines. then i'll reset the ecm and hopefully that damn light doesn't come back =P

 

EDIT: finally blew out the lines. seems clean as a whistle now, air flow from front to rear is smooth and strong. I reset the ECM, and i'm going on a 30 mile or so trip to pick something up from a friend's house, so about 60 miles round trip...hopefully the light doesn't come on.

Edited October 25, 2006 by QuismO