I got a 2003 350z last month and it's got a a/f guage. I thought it was broken cause it's always sits on lean and never moves although it still lights up. After taking it to a dealership they had mentioned that it is running lean but shouldn't b a problem. The only mods are intake and full exhaust. Headers to tips. Is it normal for it to run lean with these mods? Also how does a guy go about fixing that? It runs great and only has 7,000km on it. I plan on getting the motor built up and putting turbos on it this winter. Is this something that can be put off till then or should I get it fixed asap?
Thanks. Jeff.

 

yes, you will be lean. the only way to fix the issue is to have the car tuned

 

Ok thanks. Kinda makes sense. Is it something that should be taking care if right away? Is my motor in danger or can I leave it until summer is over?

 

Does the gauge move at all or does it just stay in one place?

 

Was just going to say...the AFR gauge is probably running on a narrow band...

 

It's just sits there barried on the lean side. The guys at the nissan dealership said it is working but I haven't seen it move in a month.

 

All this stuff was on the car when I got it.

 

I don't wanna harm the engine but being that it's gonna have to get retuned this winter anyway was gonna wait till then but if it's something that needs to be addressed right away I'll get it done.

 

What does the gauge say when you turn the key on but not the car? If it doesn't move then something is broken with the gauge/sensor.

 

Yeah it dosent move at all. There is a temp one right under it and it maxed out then returns to zero when I turn the ignition on. I figured it just didn't work but it got me thinking when the dealership had it hooked up to the scanner and them told me it was running lean. But being I have those mods that would make it run a little lean as well am I right? And if so is it a problem? Would it throw it out that much that it would cause problems?

 

Those mods will lean it out a little, but that's ok since the stock tune is rich. If your worried about it get uprev and get a tune to get it fixed, or fix your gauge so you can watch it for piece of mind.

 

Right on. Thanks for the info guys. Appreciate it👍

 

The gauge doesn't work.

 

How did the dealership know she was running lean? Why did they have her? Do you know the previous owner? If they just looked at the same gauge you looked at...that doesn't mean much. Also if they just saw that you had full exhaust, but didn't actually diagnose, that doesn't mean much either.

Yes you'll be running lean with full exhaust. I wonder why someone would have put a wideband in if they didn't get a tune, or at least were going to get a tune before selling. 7,000 km for a 2003 is pretty damn low amount of kilometers...do you know the story behind this?

If you're just driving normally (what does that mean?), not redlining her or getting on it too hard/often, I think it would be ok to wait a while if you plan on tuning in a few months. Stock tune is really rich at redline, so it hopefully wouldn't matter too much anyways. Plenty of people have waited a while to get tuned and have the mods you have. I think most people get all the aftermarket bolt-ons they want...and then get a tune.

But it definitely couldn't hurt to go ahead. Peace of mind, plus a little more power. If she seems to be running fine and you're not excessively abusing her, I'd probably wait.

 

I took it in cause the intake was like 2" off the ground. It had rained hard here once and although I had a pre filter on it was choking off the intake so it was running horrible. I shortened the intake so it's higher now and after it dried went back to running great. That's y the dealer had it. I assumed they had it on the scanner and that's where they came up with it. The original owner had passed away and the car just sat in a garage. He had a sl 500 as well so he drove that all the time. Other then that the 350 just sat in the garage for years on end. He also put ap brakes. A ings body kit and carbon fibre spoiler and hood. I think he got the car started building it and just lost Interest. From what I gathered there was a turbo kit for it too but it never came up after his death. I don't drive the car hard. Just normal daily driving and playing around a bit. Although I am goinf to the track tomorrow with some friends to do this on track experience where we follow a pace car around the track at high speed. Yes 7000 is extremely low. It's like brand new. Cars mint other then a crack in the rear bumper. I changed all the fluids and spark plugs. I've only been driving it for a month and other then the Intake thing it's ran great. When he said it's running lean I asked if the guage actually works and he said yes bit that was the service adviser so who knows. That's y I had asked on here. I only plan on driving it for another month and then I go back to work so back in the garage it goes till next year. With a little more work down to it.

 

DO NOT run lean! Get tuned! or build the engine already and tune F$@k it

 

I think you'll be fine. There are a lot of people on here that are a lot more familiar and knowledgeable with the VQ than I am, I've had my 07 (HR = different motor) since last June. I only have a handful of posts, but have been on this site researching about anything I want to mod since I got her. I've read a bunch of different threads where people will do full bolt-ons before tuning, spanning years sometimes before actually getting a tune. The stock tune is pretty rich up top, which is one of the reasons I'm waiting to tune for a while. I have stock exhaust manifolds, running test pipes and duals. K&N filters. I play, but I don't play too hard too often, so I'm ok with waiting a while.

Like I said as long as you're not abusing the bejesus out of her, you should be good. Only you know how you drive and you say she runs great. Everyone on here will tell you to search because this type of stuff honestly has been posted numerous times. And I agree, if you're wanting to mod her, you need to know what you're doing right?

 

Yeah it's not getting ran hard. Play around here and there but that's it. From what I've heard and researched I think I'll b ok. Just figured id ask guys who got a little more experience with these cars. It's my first z. I've had bad experiences with dealerships so I don't just take their word for it.