1kzte stuttering/misfiring and black smoke

[KZJ95Beast]

Yesterday my prado decided to misfire and puff black smoke while in traffic. Then drove normal for an hour or so. Switched off at destination and started normal, drove normal for 25 mins then started back. Got worse now and started surging the vehicle forward at times but also puffs of black smoke when it misfires. It was starting to do this so bad I had to pull aside. After letting it sit for 10 mind, started up and drove normal for 10 mins and started back.

Came home and changed fuel filter and same issue. Bled the fuel lines and same thing. This morning I started it normal and drove normal, full power etc. Decided to use it to go meet a customer and then started back in traffic and managed to reach location. Coming back home, every few mins it misfires until I almost reached home, it was badly missing and black smoking, pushing forward and cutting off a few times. Hard starting as well. Im confused as what's happening.

Anyone have ideas? Not losing coolant, temps are perfect all the time so I dunno what's the issue.

 

[KZJ95Beast]

I'll upload a video on YouTube and post link

 

[KZJ95Beast]

 

[javelinadave]

Have you considered contaminated fuel?
I’m just guessing but worth looking into.

 

[KZJ95Beast]

Have you considered contaminated fuel?
I’m just guessing but worth looking into.

The night before, i filled up, so possibly. However my other vehicle, 2L hilux, same fill up day after but no issues on that van.

Poured some diesel in a clear bottle, no signs of any water.

I'm seeing some symptoms of a bad primer pump is similar to my issues so I will change that today, and run it the same way and see if it helps.

If not I will drop the tank and empty the fuel and see what's in there and possible clear out the fuel lines.

 

[KZJ95Beast]

Here's the diesel I put in a bottle from after primer pump

 

[KZJ95Beast]

Just changed the primer pump, same issue after driving for about 20 minutes. I guess next step is to take down the tank and also check fuel lines

 

[OM617YOTA]

My gut feeling is something is heating up and sticking, creating an injection or timing issue.

I'm just learning about these 1KZTE's, but if it was my 617, I would start by recreating the problem, then loosening the injection lines one by one to shut off individual cylinders while the engine is running. See if the problem goes away and becomes just a dead cylinder and not a misfire with a specific cylinder, or if it's spread across all for, which it doesn't sound like. Pull that problem injector, swap it into another cylinder, then repeat the test and see if the problem followed the injector to the new cylinder. If it does, you have an injector problem.

 

[KZJ95Beast]

Not sure if it's a misfire issue or just a black smoke stutter from air or bad fuel. Slackening each injector lines one by one and each cylinder misfires and fuel sprays out, no bubbles etc. If I rev the vehicle it revs smooth and no sputter with smoke.

I drained the fuel and put fresh fuel and changed the hoses incase any has a cut or leak sucking air.

Now gonna test it out.

 

[KZJ95Beast]

So the issue was a broken wire on the sensor on top the injector pump. I decided to shake up the harness and realized the issue happening. The wires looked nornal, however one wire inside the case was breaking hence the random timings.

Been working perfectly since I repinned it

 

[OM617YOTA]

Great to hear!