Motor Missfiring problems

Howdy everybody! This is my 1st post and I appreciate any help i can get.
I bought my sisters used 97 T100 v6 S/C with both heads blown.I got a pull out 96 t100 motor from the local junkyard, and swapped it out leaving it normal aspirated. With motor in, vacuum lines matching the 97's diagram, i started it up. motor fired up 1st try but is missing. The truck is throwing 2 codes. First is a PO450 (Evaporative Emission Control System Pressure Sensor Malfunction) and P0306 (misfire on cylinder #6.)

I'm not to worried about the p0450 right now, but im trying to get the misfire tackled.

I have Replaced with new spark plugs
Swapped coil packs with wires
Swapped injector 1 to 2 ……3 to 4 … 5 to 6
Check coil ohms on injector 13 ohms (all 6 where 13ohms)
Check voltage from ECU that feeds # 6 injector 12vdc
Checked for any loose grounds
replaced fuel pressure regulator
Check compression 130psi on all 6 cylinders

Still misfiring on #6 and p0450

Any ideas before i pull the head and look for anything screwy with the valves? I know this is not a tacoma and this is a tacoma fourm, but the motors are pretty close to being the same.
Thanks in advance!

 

Hmm, sounds like you're doing all the right things, but I'm curious, you say the other motor was super charged is there any MODS done electrically to ECU necessary to accomodate a super charger ??

 

No MODS that I know of. The supercharger was installed at a Toyota dealer ten years ago.

 

I got my code reader back today and hooked it up. It was reading fuel trims at 0%(long and short), and was reading o volts for the 02 senser.
I'm going back right now and checking all the connections for the 02s, but is there anything else that i should check?
Thanks

 

OK cancel that last post. The code readers batteries were bad... now hooked up running will throw PO306.. and when the truck starts to warm up, roughly 150f coolant temp. It throws p0304 (cylinder 4) and p0300(random misfire) and runs really rough and the check engine light flashes. So i turned it off. I'm still not having the truck adjust its fuel trims. Which i dont know if it would with misfires recorded. Just for fun i switched out this trucks ECU with my Soon to be race motors ecu and it still failed so i'm eliminated that option....so im left with more questions than answers..lol any ideas?

 

Damn bro' , aint that the way it always goes, eletrical issues are found in 1 of 2 ways.... You either find it right away or bring your lunch cause its going to be a looooong day !!

 

Haha aint that the truth. Well i am going to try to change out the fuel filter since i know its never been changed. Wish i could check fuel pressure, but theres no tap, and the dealer says the union you need, does not exist.

 

OK update time. Found out from when the last motor blew, water leaked into the muffler and cat. Went and drove it for about a half hour to get the exhaust all cleared, no more smoke. Motor seams to be doing good while driving, but will misfire while idling, and will throw misfire 1-6 randomly. Its a real bad idle at 700 rpms and running really rough with and without the ac on. Cleaned the MAS and when driving still running really rough, but has not died at a light yet any other ideas?

 

If the ecm was flashed at the dealer for a supercharger in turn the ecm is looking for a boost and that could be the reason behind it.


What are the current codes it is sending now?

EDIT: check all your grounds to battery with a meter on the engine. Check for any RUST around the ground.

 

Codes are P0300,1,2,3,4,5,6

But mostly P0300 P0304, P0306.
The motor runs smoothly around 900 RPMs but anything below that is rough.
I did plug in my Tacoma's 97 v6 factory ECU with the same results.

 

OK then ecu is out.


Things off the top of my head that would make it do this.

Check, With a meter check BOTH coils on one coil pack, check primary , and second coils. Check the spark plug wires... replace if needed

If those check out OK.

Check cam shaft sensor, IAC, and TPS. Make sure your TPS is set correct. IF not the ECU likes to play a hunting game on idle also.

Even tho the injectors are ok by the coils you have have a bad disk in the injector it would not show up on the volt meter. with the engine idle see if you hear one of the injectors ticking real loud.

 

I used what the all knowing auto zone computer told me what was required. they were a single electrode, pre-gaped() i was told i could not re gap. and i threw away the box..but i thought there where .41...but i dont know for sure. i can pull one out when it cools and check?

 

my brother has a '02 2.7L that developed similar symptoms at ~240k miles that we couldn't track down. it was showing everything that told us it was burnt valves, but my brother didn't want to accept it. after trying everything, he finally got a friend to tear the top end off. surprise, 2 burnt valves. he got the head rebuilt and all is good now.

 

OK conclusion time! Long story short the only problem was the wires on #6, #4 were backwards i followed the diagram in the Chilton's manual which was, well not 100% accurate. Switched over, now it runs like a sewing machine! thanks for everybody's help!

 

NICE