jco9288

hey guys new to the form so please be easy,

So a few days ago I took a corner and my car went into limp mode, like it was bouncing rev at around 2500. It gets better....over the last few days of trying to figure this issue out I made some more discoveries.

what triggers this "limp mode" seems to be only when I take a right hand corner, like onto another street, regardless of what gear I'm in. No issues with left turns whatsoever. I also have to be pushing the car a little bit around the corner. If I go easy on a right turn it just does a little flutter/hiccup and then is fine. If im also taking a right corner at speed (35+mph pushing a little bit) it does a little flutter/power loss or goes into complete limp mode and slows down. It doesn't matter if I have VDC turned on or off and once this limp mode is triggered, the slip light does NOT come on and neither does the check engine light. I even drove it in limp mode for about ten miles trying to set a code but nothing ( which is very annoying cause you can't shift past 2000 rpm or it starts violently bucking). If I turn the car off and let it sit for about a minute then start it up, it's fine....until another right turn. I hooked up a scan tool anyways and it says everything is fine even when it is running in limp mode.

Some help would relly be great guys, I've searched other threads but everyone else gets codes set off and flashing lights and such,unfortunately my baby is leavin me in the dark...

03 350z, 103,000 mi, 6spd, kinetix velocity manifold, act stage 2 clutch and lightweight flywheel, greddy evo 3 exhaust w/test pipes, no tune......all mods have been on car for minimum 30,000 mi with no issues

Spike100

What are your tire sizes? --Spike

jco9288

Infinity G37 19" wheels, fronts are 225/45 and rears are 275/35. Front tires have been on for over a year and the rear ones got put on about 8 months ago. this issue started about four days ago

Spike100

It's no surprise you are experiencing difficulties. Your front tires are way too tall.

You can solve the problem simply by mounting the correctly sized tires on the front. A good size for the front with your 19" wheels is 245/35-19".

--Spike

jco9288

But they've been on the car for over a year with no problems and have less sidewall than the rears...why would the problem start now? I've also done autocross for almost the life of those front tires, that's pushing the car way harder than on the streets for sure

Spike100

^^ The problem didn’t show itself until there was some tire wear. That’s not uncommon.

Your front tire is way too tall (about an inch, which is huge). The rears are more worn, and slipping a little, and that is why you see the problem now. --Spike

omgitsweasel

it could be because in that year that youve had your tires, they have worn past the 3% difference that the VDC system is reliant on.
But, if I, and all the other Zs ive driven, run a wheel setup that isnt in that 3% window, i can just turn off VDC and the car continues working like a normal car. No limp mode.
I dont know if there were any revisions to the VDC system behavior between years though.

jco9288

alright, the front tires have been at the wear bars on the outside and the insides are worn even more and are ready to be replaced so ill definitely change the size. The rears are still around 40% life. As for the vdc, if you mean turning off as in hitting the button, I do that every time I start the car. Wether it is on or off this issue still occurs. Or you're talking about completely disabling the system some other way?

TuckerE36

iTrader: (3)

I find it hilarious how every new member is afraid of being flamed on this particular forum...

Spike100

You could have the problem you describe even when running the correct size tires if there is significant tread wear.

When you replace the fronts, go with 245/35-19” That size will be a good match for your 275/35-19” rear tires.

--Spike

Spike100

I agree, and that should not be the case. We have a few senior members here who have become bored and only attack new members’ posts.

I have grown tired of this “bad boy behavior,” and I take the attack back to the senior member. They of course spew some more venom and try to be cute and clever, but they realize that they are wrong, and eventually they recant. There are a couple stubborn cases, but if the members stay on them, they will either reform or they will leave. Either result is good for my350z.com.

We need to rid the Forum of people who never provide support or interest, and whose only purpose here is attacking new and existing members.

--Spike

omgitsweasel

On certain trim models, there is a grey harness plug right near the ABS module under the brake/clutch reservoirs. If you unplug that, it disables VDC and ABS. If you have that plug, unplug it, wrap the exposed harnesses in something waterproof and go for a drive. Try that and see if you still go into limp mode.

jco9288

Well guys I really appreciate the help, I might try to disable the vdc for the time being until I get some new tires. Nothing bugs me more than something that doesn't run the way it should

Spike100

It’s OK to disable VDC for the track, but foolish to do this for street driving. If you need new tires, get those now. Otherwise, you may be the next person posting another “I wrecked my Z” thread.

--Spike

omgitsweasel

i was only offering this test as a way to see if it is indeed the VDC/ABS system or if it still persists. common sense would say not to disable things like that permanently. honestly it could be something like a wire shorting out. removing power totally from the VDC system will allow him to better pinpoint the issue.

Spike100

Yes, I understand. And, in no way did I mean to criticize your very good advice. --Spike

jco9288

Just undid that plug, it turned on the abs, brake, vdc off, and slip lights on my dash (makes sense), went for a drive and it still went into limp mode

Spike100

When the tire size is wrong, you get inconsistent results from VDC, TCS, ABS, and other warning/safety systems. I would expect the result you had.

If you install the correct tire size, these problems will go away.

--Spike

jco9288

okay thanks for all the help, I'll let everyone know how it goes in a week or two

dessidee90

i agree. Im on this forum A LOT and people are being flammed over the smallest things. Its refreshing to see that this forum has helpful members tho