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Discussion Starter · #1 ·
Alright I’m having a very weird problem from my car I had a check engine light for timing chain and I’ve got all that work done and this problem started around the same time as this but it was hard to tell because of the timing issues. So at idle my car vibrates or when stop and when Turing the wheel when stops almost feels like the car will die or stall on me and when the car isn’t warm around 2000 rpm’s it’s sounds like it’s starting to surge the rpm’s also sound more apparent when more giving more gas. A code popped up p0496 and all I could find was replacing the purge vent valve which I did and idk if that helped it’s been a few weeks since then but it seems the car hasn’t changed at all I’ve also replace the maf sensor and gas car I also have the vent valve canister solenoid that’s by the gas tank but I’ve not replace it yet idk if this will cause the surging to go away or the shaking at idle if anyone can bring me some more incite on this or had the same problem I would appreciate the help.
 

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What diagnostic codes and//or symptoms were present to necessitate timing chain repair? Which components were replaced? The purge solenoid is located under the hood. The vent solenoid is located near the gas tank. Are you working on the vehicle or someone else?
 

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Discussion Starter · #3 ·
What diagnostic codes and//or symptoms were present to necessitate timing chain repair? Which components were replaced? The purge solenoid is located under the hood. The vent solenoid is located near the gas tank. Are you working on the vehicle or someone else?
Well the main one P0008 and all the other corresponding timing codes they only went away after I replaced the timing chain too. I had tried and read it could be sensors so I replaced those then decided timing chain after having no luck with replacing sensors. And everything timing related is new and other things as well like valve cover gaskets spark tube seals all that stuff as well. P0496 was the one and only code that popped up and I was told it was the back vent solenoid but I couldn’t find anything online everyone said replace the one under the hood which I did no engine code but car still run crapping at idle or at cold I’ve not had the code come back but I also don’t know if this stuff could be from dirty spark plugs or some other thing seems to be signs of a bad vacuum seal which is what the said the p0496 code was with the gas tank and it was the vent solenoid which I don’t have the tools to do yet but plan on it.
 

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Let me know how that goes for you. I'm in the process of changing out that whole charcoal canister assembly(the vent valve/solenoid is part of that). All I'm going to say is good luck. You have to drop the exhaust, the driveshaft and the rear differential just to get at it. It's bolted to the body above the rear differential. Two 10 mm head bolts and it's down.
 

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The service manual reads like all of the EVAP systems components had to pass their self testing requirements. Course it could be that one or more of them could actually have a problem, but would "not" be recognized as a fault code reporting issue. One of the problems associated with that P0496 fault, is not being able to reach the required vacuum psi in the tank. Like a faulty canister vent valve saying its closed (but may have its exhaust port partially jammed open due to crud). That in turn would make it pretty much impossible for the vacuum supply from the engine passing thru the purge valve, to reach the desired psi in the tank (let alone maintain it) within the expected time frame allowed. Or you might have a somewhat plugged up purge vacuum line. That might make it difficult for the fuel tank to reach that vacuum level required within the time allowed. Failed tries gets you a P0496 code.
 

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Discussion Starter · #6 ·
Let me know how that goes for you. I'm in the process of changing out that whole charcoal canister assembly(the vent valve/solenoid is part of that). All I'm going to say is good luck. You have to drop the exhaust, the driveshaft and the rear differential just to get at it. It's bolted to the body above the rear differential. Two 10 mm head bolts and it's down.
Well I don’t think it’s that one I’ve read you take the rest right she’ll off and it’s right behind where the gas tank hose goes to or around that area seems pretty simple but idk about that other thing lol
 

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Discussion Starter · #7 ·
The service manual reads like all of the EVAP systems components had to pass their self testing requirements. Course it could be that one or more of them could actually have a problem, but would "not" be recognized as a fault code reporting issue. One of the problems associated with that P0496 fault, is not being able to reach the required vacuum psi in the tank. Like a faulty canister vent valve saying its closed (but may have its exhaust port partially jammed open due to crud). That in turn would make it pretty much impossible for the vacuum supply from the engine passing thru the purge valve, to reach the desired psi in the tank (let alone maintain it) within the expected time frame allowed. Or you might have a somewhat plugged up purge vacuum line. That might make it difficult for the fuel tank to reach that vacuum level required within the time allowed. Failed tries gets you a P0496 code.
Wow thanks this helps me have a better understanding of all of this I guess lol well only way to find out is if I replace the part so when I can I’ll try.
 

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The 496 is vacuum in tank when not commanded to, if you replaced the engine side purge valve, you might want to check that no debris from cannister is inside new valve or lines, if it was from a wrong reading from vapor sensor it would not run bad at all, seems like purge valve is letting vapors into eng. when not wanted, common on all those 3.6
 

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Discussion Starter · #9 ·
The 496 is vacuum in tank when not commanded to, if you replaced the engine side purge valve, you might want to check that no debris from cannister is inside new valve or lines, if it was from a wrong reading from vapor sensor it would not run bad at all, seems like purge valve is letting vapors into eng. when not wanted, common on all those 3.6
Yeah I replaced it I’m not sure how to check if there’s debri in the lines if someone could help me out but I believe I’ve got a leak though since it’s kinda shaky.
 

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you can remove new purge sol, and smack inlet on a napkin if there is dark crumbs coming out, it is sucking debris in valve holding it open, also if you disconnect 2 wire connector and plastic hose, if it is sucking vacuum while connector is off you found it
 

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Discussion Starter · #11 ·
you can remove new purge sol, and smack inlet on a napkin if there is dark crumbs coming out, it is sucking debris in valve holding it open, also if you disconnect 2 wire connector and plastic hose, if it is sucking vacuum while connector is off you found it
Alright I’ll check I’ve replaced it twice with no luck so I don’t believe there’s two faulty purge solenoids but who know maybe they are I’ve read it could be a pressure sensor on the tank as well but I’ll look into it. My vibration could be from maybe dirty spark plugs cause by the timing chain issuers black them pretty bad from it being my daily. I could look into changing at that stuff.
 

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Discussion Starter · #12 ·
you can remove new purge sol, and smack inlet on a napkin if there is dark crumbs coming out, it is sucking debris in valve holding it open, also if you disconnect 2 wire connector and plastic hose, if it is sucking vacuum while connector is off you found it
Alright also let’s say the line is clogged how would I go about unclogging the lines lol.
 

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If there is debris in the new sol, you will have to remove both ends at sol and charcoal cannister at tank, spray with carb cleaner etc. and blow through with compressed air, if you find many crumb like debris the charcoal cannister is breaking apart internally
 
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