5vz missfire/headgasket questions

tldr: 5vz white smoke out exhaust after injector replacement





I bought a 95 xcab 5vz last year, thinking the engine had a blown headgasket, info from the previous owner wasn’t extremely clear. Pulled spark plugs and turned it over, everything seemed fine so I started it and it ran fine, not much in the way of problems for about a year, then got a cyl 4 missfire, coil packs had high resistance so I replaced those and that didn’t solve it, so I decided I would throw new injectors in it. I have a small bit of experience working on vehicles and a shit Ton of tools available so I figured I’d try it myself and hopefully learn a thing or two (fully aware that I was biting off more than I could chew but I have a spare engine, long story) I managed to put everything back together, and it took a bit to get started, and then it did and sounds and feels way better, no missfire, but is puffin white smoke out the exhaust. I believe I have reached the end of my expertise and I just have a lot of unanswered questions, hoping to find someone hear that might have some more knowledge then me and can point me in the right direction

 

I'll take a swing at playing internet mechanic. While it's smoking pull a vacuum line and see if it clears up the smoke while it's off. Sometime a very rich mixture will smoke white in gas engines. Also what kind of injectors?

 

Compression test, if found to be bad, then a leakdown test if you want to know where the leak is specifically.

https://www.youtube.com/watch?v=voLBRDZL9fE

https://www.youtube.com/watch?v=iSFpwnCuBDk

 

I went with denso remans from motorwest, did the full six. I’ll try the vacuum line next chance I get (currently sitting in my farms shop out of town), is there anything I might’ve done wrong to cause it to run rich?

 

Make sure you didn’t mix up the lines on the throttle body. Two are coolant one is vacuum. I’ve seen that before and it will suck coolant right down the intake

 

it could be alot of things and admittedly i'm not A Toyota tech so idk the common spots to check. only other times i've ran into this issue was with a 92 4runner and that one's issue was the cold start/7th injector leaking badly intermittently causing similar symptoms. Second was my old ranger because I changed the injectors without proper diag (turned out to be the fuel pump pressure regulator sticking in the tank, as it was a returnless system, causing the injectors to always pump out too much fuel) which lead to worsening of the issue because I used cheap random white box injectors where all 6 leaked and would smoke white even when it was 25*C and the engine was warm. Also made it hard for the engine to reach operating temperature along with a rough idle and a hard restarting of the engine when it was hot.

To answer your question go back over everything you touched and make sure it was installed right. Could possibly be something that was forgotten about during reassembly.

 

I’m hesitant to tear everything back apart without knowing what exactly I’m looking for, and if I’d missed it in the first place I’m not sure I would find it again and run the risk of making it worse, from what I can see and based of the checklist I made everything is where it was, is there a chance that I could’ve slipped an o ring to make it leak excessively? Or possibly messed something up in the fuel pressure regulator? When I first started it after everything was back together it had also leaked fuel out of the headers, not sure if any of this is useful info I’m just looking for anything I can get, thanks!