Hey guys! So i have an 03 350z 6 speed. About 2 weeks ago i was driving fine then all of the sudden, my car sounded like it had a misfire. Luckily got it home and as soon as i went to back it up it stalled. There are no codes and no lights on the dash. I replaced the maf, spark plugs, and an ignition coil. Cylinder #6 had some oil in it but not alot at all so i thought it could have possibly shorted the coil. So now when i start it, it takes a seconds or 2 more than usual but sounds great for the first 10 seconds. Then slowly goes down in rpms and then idles really rough or just recently, it stalls.Any ideas guys? Miss driving her especially with this weather!

 

My advice: stop driving your car. Tow it to a shop that has the proper diagnostic equipment. You'll save a ton of money. You're just throwing parts at a problem and wasting your time and cash.

You didn't mention your mileage.

 

That's what im about to do. I have 109k miles on her. Hate taking cars to the shop but i might just have to deal with it. Just wanted to see if anyone has had similar problems with the no code deal. Really sucks that i cant pinpoint the problem but hopefully a shop will. Thanks!

 

Here's the problem: If you don't have at least a decent live scan tool where you can record relevant data from open to closed loop during a driving cycle and if you don't know how to interpret that data, you're going to have a hard time nailing down what you believe is an unregistered misfire. Ideally, a relative compression test performed using a lab scope will give you a good idea which cylinder is misfiring. With that, a live scan will register any unrecorded misfire readings (meaning occasional misfires that aren't occurring often enough to throw a code.)

If you can do this, then we could go into further discussion. If you can't, then take it to a shop. Since you're not getting any codes, it's difficult to diagnose problems like the one you're having without actually being there. Any advice you get should be taken with a grain of salt if there's no evidence to back it up, since there's a reasonable likelihood that you'll just be replacing a part that doesn't need replacement.

Based on your mileage, your car is ready for a scheduled maintenance check anyway.

It's always useful if you can describe your technical abilities relating to engine repair before you throw a diagnostic question out there, especially if you're brand new to a board.