Hi everyone,

I have a 2003 350z Touring A/T. It has 222K miles on the odometer. I bought it used about 2 years ago in the Summer of 2021 for $2000. The previous owner said the engine was replaced at some point (I think by the owner before him), and it has about 125k miles on the engine now. It is still a VQ35DE engine.

Not a lot of mods to it - Takeda cold air intake which was already installed when I bought it. Has an aftermarket pioneer head-unit which was also already installed. I put on an Invidia N1 exhaust over this summer, and didn't have any problems with the car after that.

The problem started about a month, month and a half ago. I just replaced the rear bumper (old one had a lot of damage from previous owner doing a terrible exhaust cutout job), and I was on my way to work. I got to the second stop sign and the engine just shut off. No lights came on besides the normal lights that would be on when you have your key in the 'on' position, but engine isn't started. I tried to start it again and the car would crank but wouldn't start for a bit, until about 5 minutes later when it did. I didn't want it to happen again so I just parked and drove my daily to work instead.

After doing some research, I came to the likely conclusion that it was time to replace the crankshaft position sensor and the camshaft position sensors. Last week I was finally able to get around to replacing them, as the weather here hasn't been too good and I don't have anywhere indoor to work on the car. I replaced both the sensors, and took it for a few test drives. The first drive, the SES light came on after about a mile. I scanned it, got code P0011 (Passenger side timing over-advanced or something like that), but decided to try and clear it. After I cleared it, I was able to drive about 10 miles and it came on again for the same code. The car didn't seem like it had any problems - felt like it started fine, drove fine, etc.

Doing some more research, it seemed that the VVT solenoid on the passenger side could need to be replaced, so I just decided to order a new one for both driver and passenger side and replace those. I noticed that the bolt holding in the passenger side camshaft position sensor was a bit loose, so I tightened that down. The passenger side VVT solenoid came in yesterday so I figured I might as well install that too. Install went fine, but when I went to start my car, it just wouldn't. Turning the key to the on position starts the radiator fans and the TCS and slip lights are on. SES light does not turn on, I can't scan it for any codes, and the car will crank but not start.

It seems based on other posts that I most likely fried the ECU? I am not exactly sure how I did that by changing the VVT solenoid. I went to investigate today, though, and I found 2 things:

1) My fuse box that is by the battery (where you have to take some of the plastic off and such) is just completely different than any other pictures I have seen online. It looks sort of similar, but it is definitely not the same. That is the first picture on the imgur link below. I unfortunately did not take a picture of the fuse diagram on the cover, but it didn't look like anything on there was related to the ECU, so I wasn't sure where to even check for a burnt fuse.

2) The wiring on the VVT solenoid looks like part of it is broken. On the last picture, there is clearly a part where it is not connected fully. I am not sure if maybe this wire fried the ECU?

Imgur link

LMK if the imgur link does not work, I can attach the pictures in here but they would just be huge pictures. If any other details are needed, please let me know.