Car is a 2004 SE VQ35DE.
I changed the chains and tensioners, car runs but stutters and has no power. I drove it around and top speed was about 60, with hesitation and backfires. Drove it to autozone to get codes pulled, and P0300 and P1136 came out. I drove it around After the codes were pulled and it won't go above 20mph now, and usually just dies.

I'm wondering could I have mixed up the coil packs? There were no labels on the wires so I kind of just did an educated guess as to what fit best and where...

If anyone has a wiring diagram for the colors of the pack wires that would help a lot, as far as the 1,3 and 5th cylinders. Besides the common red/black power and ground wires the 1 cyl is yellow/red, 3 is green/red, and 5 is purple/white

 

http://engine-codes.com/p1136_nissan.html & http://www.obd-codes.com/p0300

As for the coil packs, it doesn't matter which one you put where. It does matter how they are plugged in. The plug wires will only reach so far. they are also bundled. I would make sure you torqued down the plugs correctly, go to autozone and get a tester and make sure all are firing. Also if one was faulty, you would get a specific code for that cylinder. P300 is generic, Follow the first link I provided and change your oil and filter, then reset the code.

 

Did you double and triple check your timing? One of those chains might be off.

 

Hopefully you marked everything before disassembling, and aligned when you put the new chains and tensioners in. If not, MoncefA33 might be correct.

 

Sorry for the late reply, been busy at work.

Ok so after I posted this I messed with the coils and got them into the correct order, 2 of them were mixed up.

After I did that however the engine started smoking from the valve covers. I'm talking visible smoke seeping thru the valve cover gaskets and out of the oil filler cap if I take it off.

Today I just tore the engine apart again and redid the timing as per the manual on http://www.nicoclub.com/FSM/Maxima/2004/

#1 cyl at TDC, cams both in their correct positions with the small hole/dowel pins facing up and out.

Buttoned it all up, ran a lot better but still a little low on power and still smoking out from the valve covers.

I really have no idea wtf to do anymore

 

The second code you have is related to the VDC solenoid on bank 2 which is closest to the radiator. Take a ohm meter and measure the resistance between the two terminals of the solenoid. It should be between 7-7.5 ohms. If its outside the range, you need a new solenoid. Another issue might be is that you're not getting nay oil to the VTC solenoid, did you replace the small rubber o ring on the timing cover when you did this job?

 

I don't remember there being any o-rings on the cover, and didn't replace any

 

You should not see smoke coming from the valve cover gasket. That means you have a leak in your gasket and it needs replaced. If you used the right sealant for the timing chain cover, it will smoke a little at first until it burns off the excess. You should run it at temp for a while then change the oil. I recommend using a high viscosity oil (recommend Mobile 1 15w50) as a replacement to ensure good lubrication throughout. The Timing chain is lubricated by the oil pump. Hopefully it is operating correctly and getting the oil where it needs to be. Hope this helps. The valve cover gaskets are real easy to replace and don't cost a whole lot. You can even do like I did and get the poly lifetime guarantee gaskets. http://www.autozone.com/autozone/acc..._&target=shelf pretty sure this is what I purchased. It is a poly composite molded gasket.