I have an 04 350z enthusiast roadster with 133k miles, just purchased it 3 days ago. It has an engine tick that matches the rpm's when I rev the engine, the tick speeds up with the revs. It doesn't cause much performance issues as far as driving, but when I am idling, it idles fine for like 10 seconds, then will bog down a little bit almost like its gonna die for a second or 2 then it goes back to normal for another 10 seconds. I actually think the idle issue is more related to my P0171 and P0174 code. Someone told me it could be a bad injector causing these codes and the tick, but I don't know if the tick and the codes are related or 2 totally different issues. I've also been told it sounds like a lifter, by multiple people who were fairly certain that was the issue, but with the codes along with it, I want to get some more opinions, because when i asked about the codes they had no idea what to think of it. I have also read that those 2 codes can be caused by an intake leak. Thoughts and opinions? would be much appreciated, I just want to Zed to run smoothly.

 

Lifter buckets is my guess, rather common issues and can be expensive.

 

A single bad injector won't cause lean codes on both banks. Might be your MAF dirty or going bad. Do you have an aftermarket intake or oiled air filter?

 

I don't think so, I just bought the car a few days ago, it's not modded as far as I can tell so I doubt it. It's gotten a little worse since I posted this, it now bogs down to even lower RPM's, also I can hear some kind of high pitched sucking/whistling noise occasionally

 

Vacuum leak somewhere.

 

Check the intake boot/plastic tube. its prob cracked.