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2004 350z won't start after engine swap

**Before I explain my situation let me say that I have searched the forums constantly for weeks, and while I have found useful information I haven't solved my current issue.

I have an 04 350z 6 speed and about 6 months ago the engine went. I swapped in a vq35de non-revup out of a g35 Coupe automatic and just swapped over my clutch and flywheel onto the new-to-me engine in place of the torque converter. Still using my original ECU and harness. Once everything was back together the car would crank and crank but not start and run. I dropped the crank sensor and it started and ran, but very poorly. I assumed the flywheel was positioned wrong so I dropped the transmission and sure enough it was. So I lined it up correctly with the dial pin on the crank and put it back together. It still wouldn't start and run, so I dropped the crank sensor again and it fired right up. It ran and idled smooth. I don't see how it could be the flywheel again since I aligned it correctly this time, but it won't run with the crank sensor installed at all. Already replaced both cam sensors and crank sensor, and still nothing. Kind of at a loss here, if anyone has any info to help me it would be greatly appreciated, thanks.

What flywheel are you using?
The crank sensor may not be damaged, but it's possible the wiring harness was during the swap. You may need to bust out the shop manual and do some continuity tests on the crank sensor wiring. If you disconnect the sensor and the engine cranks and starts, but won't start with the crank sensor connected, then I think it's pretty clear the issue points to the crank sensor or the wiring. The only other possibility I can think of is the flywheel. If you have it aligned properly with the pin, perhaps there's a defect with flywheel index locations that the crank sensors reads.

Me personally, I would start by inspecting the crank sensor wiring and make sure it's not damaged.
Good Luck!
-Icer

I remember reading something about swapping out the rear pilot bearing when swapping out an engine from an automatic car...

Other then that I got nothing.

Quote:

Originally Posted by icer5160 (Post 10965341)

Thanks for the response, the flywheel I'm using is just the OEM flywheel from my previous engine. Maybe the flywheel was damaged somehow I'm not sure. It's very strange though. When I started the car without the crank sensor installed it definitely wasn't running 100%, and seemed sort of rough in the revs but I did drive it into my garage. If I don't find any issues with the crank sensor wiring my next step will be just to replace the flywheel with an aftermarket one and see if that changes anything. Thanks for your help

Quote:

Originally Posted by dboyzalter (Post 10965342)

I remember reading something about swapping out the rear pilot bearing when swapping out an engine from an automatic car...

Other then that I got nothing.

Yes you're correct, and I did remove the pilot bearing from the automatic before installing the clutch. Was a PITA but I finally got it out lol. The clutch mounted fine after that

i wen't through pretty much the exact same scenario, mis aligned flywheel and all. Ended up being that I blew an ecu fuse by the pcbm and didn't put the fuel pump fuse back in.

Quote:

Originally Posted by Kevin Skene (Post 10965502)

i wen't through pretty much the exact same scenario, mis aligned flywheel and all. Ended up being that I blew an ecu fuse by the pcbm and didn't put the fuel pump fuse back in.

Thanks so much for the response. Well I went and checked the fuse box behind the battery and sure enough I found that one of the fuses was blown. It's a 10A fuse and that's the only one that's blown. I'll replace it first thing in the morning and see what happens, I hope that's the issue. I couldn't find any info relating to this fuse, as it seems most people with this issue are finding blown 15A and 20A fuses. I'll update this tomorrow with results

Quote:

Originally Posted by z33cole (Post 10965509)

Meh. Could be anything. On the cover of that fuse panel is a list of everything.

I have 04 G35 that I have recently put back together from previous owner. So it cranks over fine, bit wont start.
I've swapped out cam sensors and 2 coil packs. I had no injector pulse prior to swap of sensors. It tries to start but no go. Pulled plugs found 2 coils not firing, still no luck. Security light goes out with key on, no codes with snap on modus scanner. Have tried tps relearn also with no luck.fuel pump is working and no bad fuses that I can find.
little help would be appreciated.