Longest video I could put

 

Smoke is also coming out of the intake, when I shut the vehicle off, any idea why?

 

I do see the smoke but it’s not what I would consider excessive, and given the idling problem, it could be normal in that fuel/oil/moisture is collecting in the exhaust and burning off as the exhaust is warming up.

It’s not uncommon to see the fuel pressure fluctuating with the engine running - the question is how much is it fluctuating (lowest number to highest number, as best as you can tell).

Depending on the VIN code for the engine (8th digit), fuel pressure spec is as follows. This is key on, engine off, and should hold pressure for at least 2 minutes with no more than 5 PSI loss.

VIN codes V, T, U - 55-62 PSI
VIN code Z - 48-54 PSI

Smoke in the intake could be caused by a few different things but my first suspect is the fuel pressure regulator. Disconnect the vacuum line from the fuel pressure regulator - if you see gas dripping from the line/regulator or can smell gas, the regulator is faulty.

Did you ever try capping off the accessory vacuum ports and checking if it idles?

EDIT: Also, this would still have an inline fuel filter on the frame rail - when is the last time it was replaced? If you’re not sure, just replace it.

 

I just replaced the regulator with a ACDelco one, and I’m going to recheck the fuel pressure later today, as well as the compression. I believe it was at 50 psi key on, engine off. And this is just a photo of the smoke, it is constant, every time I shut the engine off.

 

One important thing to note: a new part does not mean it’s a good part.

I’ve seen plenty of bad parts right out of the box, from both OEM and aftermarket, and in some cases they’ve had me chasing my tail because I didn’t question the new part. It only takes a couple of seconds to pull the vac line and verify it’s not leaking.

I’m gonna have to think on how the smoke in the intake could be that thick. Smoke like that is usually indicative of too much starter fluid (which I hope you’re not using).

That said, I highly recommend re-installing the factory air filter & boots and throw that custom air filter setup in the garbage. Those are fine for a hobby vehicle (racing, off road, etc) but on a daily driver they don’t do anything other than coat the MAF sensor and throttle body in the same oil that’s supposed to be on the filter and catching dirt.

 

Id have to find a new one, and yeah I’m gonna throw this one out once I do. And the new regulator isn’t leaking any fuel out of it, and no, I’m not using any starter fluid. And yeah I’ve found out before that new parts aren’t always good out of the box.

 

Turns out one of the cylinders were flooded, because of that leaky injector, and now it runs perfectly fine.

 

Good to know you got it figured out. Thanks for letting us know.