04 Toyota 4runner

Hey everyone im in desperate need of help. I recently tore down my yota and replaced head gaskets, timing chain, seals, mass air flow sensor, fuel pump and fuel pump relay. It will turn over but will not start. What am I missing? Please anyhelp is greatly appreciated!!

 

WHY did you replace the head gaskets, timing chain, mass air flow sensor AND the fuel pump and fuel pump relay?
The head gaskets, timing chain, water pump, and necessary gaskets are understandable.
Why did you replace the mass air flow sensor AND the fuel pump?
Was it having trouble cranking and running prior to the head gasket?
Was it having trouble cranking AFTER the head gasket and you proactively replaced the fuel pump and mass air?

The toyota ecu will cut power or fuel if its not happy about something.

 

It was cutting out real bad prior to doing all the work. Replaced the mass airflow due to it throwing the code for it. Replaced the headgaskets because they were cracked.

 

The cutting out could have been a number of things, getting coolant in the cylinder will certainly blow your spark out and cause misfires but a bad coil pack will make it run all sorts of terrible too. Aftermarket oiled air filters getting oil on the MAF are the #1 cause of MAF codes. They have to be cleaned periodically if you are running an oiled filter. That may or may not have made it run bad though.
No other codes?

 

It has thrown p0113, p0102, p0118, p0121 and p2135. Also all my coil packs are new.

 

Toyota new or auto zone new?

 

Toyota

 

0121 and 2135 would sound like your running rough troubles
the TPS isnt seeing what you are giving it, meaning your throttle on the floor, if you are at 5% throttle to get rolling but the ECU sends the signal to the throttlebody but the servo in the throttlebody isnt opening the plate to match what the ECU told it to do, then the ECU is going to throw the 0121 code. Also when you give it xxx throttle, and the throttlebody does something different, if its getting more or less air than its supposed to based on how much fuel its giving then its going to run like crap.
BUT
All of those codes together sounds like a lotta trouble in the harness, you took everything apart are you confident you got it all back together right? Did all the wiring look good? No broken clips when you pulled it all apart? It would seem like an engine ground was bad, a wiring harness was messed up, or a combo of those causing your problems.

 

Not 100% confident since it was running before I did this lol. This is also my first time going this in depth into an engine.

 

After doing all this work, have you done a complete compression tests on each cylinder?

You need 3 basic things to run, air, fuel and spark....BUT this doesn't work if there's no compression, if you have good compression I would try a little starting field in the throttle body to see if it will start or at least try to start/fire, if it does then you very likely have a fuel delivery issue.

If the compression is not good and not consistent between cylinders then I would say something in your work is not correct possible timing off.

 

Welcome