Code P0443, after replacing purge valve twice with new, this code keeps coming up?

Hi Joe, it sounds like it's under the hood. I tried locating it yesterday but couldn't find it. I'll check again today and if there's any hissing near the charcoal canister as well. I am just confused because the code says open circuit fault so I'm thinking it's the PCM. But I wonder how could a vacuum leak cause an open circuit code. Also, the clicking is continuous as soon as the PCM tries to open the purge valve. It's not just one click, it's a lot and rapid ones together

I just did a smoke test, and the leak was in the hose coming from the charcoal canister going directly into the purge valve. The leak seems to be behind the engine. Do you think if I fix this vacuum leak the rapid clicking of the purge valve will go away? Do you think the clicking happens because there is a leak, the purge valve can't stay open, so the PCM tries to reopen it?

Hi joe,

It's been a while! Hope you're doing good.

The hose I mentioned before was fine, no leaks. I took it to the mechanic and paid them 150 dollars to diagnose the issue. They came back both times with a bad o2 sensor. I have replaced them all and now I have codes p219a and b, air/ fuel ratio imbalance. And p2196 and p2198 o2s b1s1 b2s1 both stuck open and running rich. I'm taking it back Monday with little hope so they can look at it again and waste my time. The clicking is still there, the hissing is still there, it's slowly getting worse every time I try to fix it. I'll keep you updated. Take care for now.
Mario

Dear Joe,

Thank you for everything you've done so far. I got my car back from the mechanic. After he looked at it for at least an hour all he did was tighten the clamps on one little one inch hose. I'm done with them, that was the third time I took it.

Anyways I'm planning on taking it to a different mechanic to diagnose it. And if he can't find it either, I'm going to buy an advanced code scanner. Do you have any recommendations?

Thank you.
Take care,
Mario

Hi Joe,

Will do! I have good news for once, I think I've found the vacuum leak. I had seen some videos online where they tested the exhaust manifold so I suspected the intake and the exhaust manifold. I tested them both by pushing air in through the tail pipe and the intake manifold with the throttle body removed and spraying soapy water. Sure enough, the exhaust manifold gasket leaked in cylinder 6 and 3, and where the exhaust connects to the manifold and the o2 sensor right after that only on the passenger side. I'm not 100% sure this is the issue but I'm really hoping it is. And I think it's funny that it's leaking at those cylinders because that was the cylinders that had bad coils and the guy I bought the truck from a tew months ago had been driving it like that for 6 months.

Do you think the misfire had caused the cylinder to heat up more than usual causing the gasket to wear out? Because they're the only ones leaking.

I'm going to put some exhaust seal putty to try and plug up the leaks in the exhaust manifold and see if it changes anything before replacing the gasket itself. If it fixes the problem great, I'll leave it like that until it starts acting up again, then I'll replace the gasket. I am kind of scared because the exhaust manifold bolts tend to snap. As for the o2 sensor I'm going to try to tighten it some more and if it doesn't work, I'll add some Permatex copper anti seize to hopefully seal the leak.

What are your thoughts on this plan so far?

Thank you,
Mario