doc_sus

I recently swapped out the engine from my 2004 350z with another engine with fewer miles and no issues (spun a bearing). Now that the new engine is in, I cannot get it to start.

Here is what I have done so far:

Fuel is being delivered as I am able to smell it, and it did backfire 1 time since the swap/attempt to start.

I have checked the #5 coil for spark and no spark while cranking.

I next checked that specific plug and the 3 wires related to it. I got the constant battery volt reading when checking 2 of the 3 wires on the plug (the middle black wire and one of the outer wires) When checking the middle ground wire of the plug to the 3rd wire, no reading, when cranking still no reading. I have a standard volt meter and am not sure what this can tell me or if it can pick up a signal for that 3rd wire, but I got no reading.

Grounds:
I went over all the body grounds in the engine bay to make sure nothing was loose along with the battery terminals. I checked the computer plug under the passenger dash for ground (pin 115, 116, etc per FSM directions) and had everything come back okay. I even removed the cam sensor plugs to see if it would fire up that way (came across a thread that mentioned that it would start up and run but not well without the cam sensors) but it did not fire up. It cranks well and I can rule out the starter being an issue. The battery since has died, but I am able to crank it using jumper cables, but not get it running.

My vehicle is an automatic and the replacement engine is from a manual. I removed the fly wheel and replaced it with my existing flex plate. Could this be the cause of it not firing up? Is it possible to install the flex plate in a way to have it cause a no start condition? Having it installed improperly, will that lead to it not starting, or would it start and run very rough?

What steps would you recommend taking next to troubleshoot? Should the flex plate be a concern, I would much rather rule everything else out before pulling the trans to check the flex plate, IF that is a concern or possible cause of the issue.

Thanks in advance!

PP08HR

iTrader: (2)

Probably got a pinched fuel line?


If you have a fuel pressure gauge use it. Or there should be like a relief valve on fuel rail. Most cars have them, not sure about ours.


Before you take it to a dealership check for pinched fuel lines, also check over the harness for pinches or open wires.


Otherwise you'll just have to start replacing parts. Like the crank and cam sensors, coil packs, ecu's etc...


If the flywheel/flexplate was the issue it probably wouldn't crank very well or you'd get weird type hiccups when cranking.


Anyways, good luck.

doc_sus

Thanks pp08hr for the reply and help. I will check the fuel lines and harness for any issues. The coil packs are the same as on the original engine, and I had not experienced any problems with them during their use. The old engine, it had a horrible knocking noise, but I drove the car into the garage without any codes, such as misfires, and I assume and can most likely rule out the coils as being the problem, but I will swap them out with other ones that I have handy. I hope the flywheel is something I can rule out, I will keep you updated and will report back with my findings/results. I did however swap out the coil pack on cylinder 5 with another one to test for spark and still had no spark, I even tried another known working spark plug and no spark again on crank.

Can anyone else think of something that may be causing the issue? I came across others talking about having key issues to where they had to lock unlock the car several times before being able to start it. I had checked all of the fuses as well and all are in good condition.

Thanks again everyone!

doc_sus

Hi everyone and thank you for taking the time to go through this! This is my first post so I apologize if I'm doing something wrong. My issue is the following. I recently did an engine swap and finally got the replacement engine to run. It has 50000 miles on it and at idle it seems to be running rough a slight Shake in the chassis can be felt. When Feathering the throttle from idle to about 2000 3000 4000 RPM and allowing it to come back down by removing the foot from the throttle it at times and dropped pretty low and a few instances has died. I have also noticed during idle at times not always, it has feathered on its own between 7 and 900 RPMs pulsing. I have rented a OBD2 scanner and have been able to capture live feeds of it idling and have taken screenshots. Unfortunately I do not know what the values mean and hoping that somebody here can make sense of it. I have rent today oh btw to scanner and have been able to capture live feeds of it idling and have taken screenshots. Unfortunately I do not know what the values mean and hoping that somebody here can make sense of it. I have also changed every spark plug what the factory recommendation. Nothing has been upgraded or altered or any aftermarket parts have been installed. It also throws a p300 multiple cylinder misfire code. Thank you in advance and any help is greatly appreciated!

Here's the link to the video recording of what what's going on:

https://goo.gl/photos/zR4VYMA6D9NhaUho6

Thank you again!!!

doc_sus

Aww
It turned out to be the flexplate. It was off 180 degrees. Fired right up after the reinstallation.