Emission culprit

[Gussie2000]

This topic has been on the table several times,however i think is better to refresh the issue again......
Since i bought my horse back in november'08 the engine light has been an ghost following me every time i get into VX.
Ever since i had almost all emission components replaced such as cut off valve,vent solenoids (front & rear) & gas cap;The last part replaced was the charcoal canister which I did two weeks ago;All electrical conectors were tested along with the hoses & all of them are working perfect
After all that i thought my ghost would go away.but the very next day the canister was replaced my light pop up again (damn it) so that same evening
i call my mech to report the issue he said Gus,the last piece of the puzzle is the VSV (vacuum solenoid valve)
So i proceeded to reset the ECM,unpluged the VSV conector & drove the horse for the last four days with no light poping at all.
Is this VSV the guilty guy ?
How prone is VSV to fail ?
Then i tried to remove it,but found no way to get that S.O.B. oute there.
Do any of my fellow VX pals dealt with this VSV before ?
Need a how-to remove this VSV please.

Thank you !

Update :

Heading back to my house the light pop up.

Went to autozone to get the reading but was too late ( autozone don't run code reading after 6:00pm ) so i clear up the light (again) will see tomorrow.



PIC :

[Marlin]

I still get a check engine light every 4 or 5 days, P0440. Good thing about the scan gage, I can read the code and then clear it in just a few seconds. So I ignore it

[Gussie2000]

I had that same code before i started replacing all the parts,now the only code pop in is p0446.

Still waiting for some one to tell me how to remove that valve,it's located at the top-rear of the engine on the driver's side.

I'll post couple of pics to pin point the right location .

[Gussie2000]

Alright !

I figured all out.

Thanks for all the inputs

[Marlin]

Alright !

I figured all out.

Thanks for all the inputs

Aaaaaaaaannnnnnnddddddddd.........

[ZEUS]

Aaaaaaaaannnnnnnddddddddd.........

HAHAHA! Well said...

[Marlin]

HAHAHA! Well said...

When I wrote that, for some reason I was thinking of Ldub, with the exception that I did not include any dancing fruit or chocolate primates.

[Gussie2000]

The VSV is held in place by a what i will call it is a metal cover that protects the fuel pressure regulator,this cover its self is held by two phillips screws to the intake manifold,the horrible story here is that one of the screws is right behind the intake manifold,too close to the firewall & the ABS vacuum lines which makes it almost impossible to remove .

So yesterday morning i went down stairs to deal with it........After several tries i give up the screw located behind the intake manifold is just too difficult to grab on.

My mech told me that the VSV is originally in OFF position (open) so once the ECU software commands the the EVAP to test its self that valve gets onto ON position (close) so the vacuum process is initiated.

I turn on the horse for 10 minutes,i asked my girl to gas up the horse for 5 to 10 more additional minutes so the ECU will engage the EVAP to run a test,i unplugged the VSV electricall conector & use a 12v transformer to test the VSV but to be honest i wasn't able to verify its working conditions after all & no way to know if i did it the right way

Then there's a cylinder canister located next to the black fuse box which i noticed is interconected with the EGR & that VSV by a two way hoses & now wonder if that canister could be broken/clogged.

Because my mech's smock machine is off duty at this time he cannot run a smock test on my horse.

So by the mean time i got nothing to do but wait 'till my mech's smock machine is back to duty

[Marlin]

Alright, now we are getting somewhere. As for the FPR cover, search the site for fuel pressure regulator, you will see a great write up on replacement. I bought an allen key set and ground one down to fit that rear screw. After I was done, I opted to not install that rear screw. That was back in Mar before Moab, no problems to date. I am gonna take a look at my VSV out of curiosity. But ultimately, P0440 means nothing to me, just an emissions related thing, the truck runs great, no problems....knock on wood.... I am not sure what a smog test would do for you? I don't even know what that canister in the front does!!! Time to do some research when i get home from work.

[WormGod]

For what it's worth, the VSV is disconnected and not used for S/C installs. No codes thrown and passes emissions. You can always try just disconnecting it altogether and plugging the line into the manifold and looping the line on the canister. Should reset the brain after that and see what happens.

[Gussie2000]

For what it's worth, the VSV is disconnected and not used for S/C installs. No codes thrown and passes emissions. You can always try just disconnecting it altogether and plugging the line into the manifold and looping the line on the canister. Should reset the brain after that and see what happens.

I drove with the VSV's wiring disconnected & didn't thow any codes for almost a week.
I didn't get the code @ autozone due the time,but tonight i'll bypass the canister by connecting together both hose lines to see if any code pops up,then do the same procedure with the VSV.
I forgot to mention that i test the current output from the VSV wiring harness & noticed that the meter was reading 13+ volts instead of the 12v that the manual workshop states it should be running.
Could that extra 1+ volt enough to fried up the vacuum solenoid valve.?

[Marlin]

I drove with the VSV's wiring disconnected & didn't thow any codes for almost a week.
I didn't get the code @ autozone due the time,but tonight i'll bypass the canister by connecting together both hose lines to see if any code pops up,then do the same procedure with the VSV.
I forgot to mention that i test the current output from the VSV wiring harness & noticed that the meter was reading 13+ volts instead of the 12v that the manual workshop states it should be running.
Could that extra 1+ volt enough to fried up the vacuum solenoid valve.?

I would think no and that the manual is just assuming a generic 12V system. The alternator output is somewhere between 13.5 and 14.5 volts.

[Gussie2000]

Today i drove to & from my work with the two hoses connected to the canister plugged together & no MIL pop up so far.

I'll keep this set up to see if the MIL comes on & if it does get the code readed

[shinkson]

I am having a hell of a time with my VX idling. I seem to happen when the engine is cold and start suddenly and occurs randomly. I get idle hunts when in neutral and in park. I seems to run great once warm. It is my daily driver. very short run to the freeway then 27 miles to work. Never a problem on the freeway. I put my ScanXL ObD II scanner on it and notice the following;
MIL Light Codes; P0171, P0172, P0174
absolute manifold PSI Max =14.9 Mean = 8.1 Min=2.8
short term fuel trim bank 1 Max=90% (sometimes at idle) Minimum=-21%
Long term fuel trim bank 1 Max=24% Mean=10% Min=1.6
Max Air Flow Max9.1lbs/Min Min3.8lbs/min
Fuel rate Max6.1gal/hr Mean2.5gal/hr

I have changed the IAC, cleaned the Throttle body, replaced the vacuum relief valve (mounted to the supercharger, opens when in idle to relief pressure back to uncompressed side of SC). I have re-installed the intake manifold to insure there wasn't a related vacuum leak.

There is a vacuum solenoid connect to evap canister with 2 hoses. I am not sure which hose goes on which end of the solenoid.

Well that's all the info I have. Hope someone can help.

[shinkson]

Additional information - My scantool doesnt seem to be pull all the information available according to the service manual. Specifically, I am not getting fuel pressure, barometric pressure, air fuel comanded elquivalance which are needed to pull air/fuel ratio. I am using ScanXL Pro and those charts are flat lined.