It all started with misfire in cylinder #4. I changed all 6 plugs and new set of wires. I also changed the coil pack that goes to cylinders 1&4. No luck. Still misfiring. I changed all 6 injectors. 3 or 4 of the new injectors o-rings were damaged and leaking gas everywhere. Threw code for too rich bank 1. Pulled them all back out and replaced all the o-rings. Still running rich. I changed the MAF, ECT, fuel pressure regulator, fuel filter, both O2 sensors, and air filter. Still rich. I just changed the three injectors on bank1. Still no luck. I checked the compression last night in bank 1.

Compression
Cylinder 1- 185
Cylinder 3- 160
Cylinder 5- 190

I’ve ordered a new timing belt.

is there something I’m missing(other than my bank 1)???

 

Update...
I changed my timing belt and its still throwing the same codes. The old timing belt was off two/three teeth and I was sure that was the issue. NOPE!!!

 

Swap the coilpacks around and see if the misfire moves and double check to make sure you put the right wires to the right plugs.

 

Are the coil boots in good shape? They can cause a misfire if they are cracked, assuming they are new because you replaced the coils. Might also check and make sure the spring in those boots is touching the plug when its seated.
Pick up some dielectric grease and coat all the contacts for the spark plugs and coils as well.
That stuff is amazing.

 

Thanks for the reply. I ended up taking it to Toyota to get a professional opinion. They told me cylinder #3 was 125. and that was the cause of all my issues. They suggested a rebuild or to replace with a newer long block with good compression. Im not sure I buy that, but I ended up ordering a JDM and plan on installing it over the holidays. It had less miles than the one Toyota was trying to sell me for 2/3 the price. We will see. I have a feeling its something in the new parts I installed. We will see.

 

Back up for a minute, did the injectors fix the #4 cylinder misfire?
And then you got a "too rich bank 1" code so you threw a bunch of parts at it and replaced the timing belt?
If "it all started with a misfire in cylinder #4" I would assume it was running right with no codes prior to that, so....
Are you SURE the timing belt was off? was it chewed up or loose enough that it could have jumped time?
Maybe when you replaced the injectors you should have hooked up a scan tool and reset the computer's fuel mapping so it could relearn how to run with new/clean injectors. I'm not sure why it only came up with a code for bank 1 rich, but I sure wouldn't have torn into it and replaced everything without testing to see what may be faulty and you don't make it sound like you did.
There is no guarantee that your new parts aren't part of the problem, I've gotten bad components from sellers before, both new and used.
Keep this in mind if you are putting a used engine in your truck, I got a "low mileage used engine" from a wrecking yard that swore up and down it had been compression tested, but when I installed it in the car (Toyota Tercel) and tried to turn the motor by hand to bolt up the torque converter it wouldn't even make a full rotation. It had a bent rod! I guess what I am saying is, don't assume ANYTHING about replacement parts or used engines.
I suggest you test components thoroughly before you replace anything and make sure the new item is properly adjusted and passes all the tests before you replace something else.

 

The misfire did fix the issue on #4 cylinder.
I changed parts that I thought "could" be the issue due to similar issues found in different forums.
Yes it was running damn near perfect before the original misfire started
I guess I'm not a 100% sure that the timing belt was off. I do know that it didn't line up with the marks.
I installed the new( to me) engine and it is having the exact same issues. Im at a complete loss. Im thinking maybe its in the wiring harness???
Its currently on the marketplace for sale. LOL