Transmission Problem ?

[manda23]

So im driving today like normal and come to a stop at the traffic lights . When the slip light comes on. I thought at first i was seeing things and gave it a rev and sounded good so we ready to take off. Once i let out the clutch again the slip light came on and i felt i didnt have any power and then i went into second when im hearing loud cruching noises and losing power.

So i got it towed home and then tried to take her around the block. I took off in 1st it feeling like im towing something and again went into 2nd same thing no power and crunching noises.

I rang paden at united at villawood he said mate thousand's if its a transmission problem. And for me to get the car to villawood i have to get it towed from my place in sutherland.

any suggestions or mechanically mind people out that can give me some suggestions or have had a similar problem please let me know.

Thanks heaps guyss.

[whtbox]

i think it would help if you give more details of your car whether it's Manual or Auto?

[fcruz3r]

is urs a manual or auto??? ...sorry I'm just contemplating buying one but I have heard some horror stories about the transmission in these and that the syncro's are exceptionally prone to fail in the earlier 2003-04 models coz they came with 2 plates instead of 3....but that was my own internet research and I dont know how common this is (ppl only report problems on the net...so anything u hear is always negative)

[rs73]

Once i let out the clutch again ....

it's a manual...

maybe get it to Nissan dealer and get it scanned with consult diagnostic software...?

[manda23]

i think it would help if you give more details of your car whether it's Manual or Auto?

It's a manual. I'm having lub mobile come out tomorrow and check it out. But im thinking how can they check with their computer on mine when i have the impul ecu ?

Also for another notice i drove the car around the block with the lsd switch off and it seemed to work fine. But i dont want to do any further damage.

[rs73]

do u mean VDC? or LSD as in mechanical LSD they put for racing cars?

crunching noise sounds like synchro problems, but turning off VDC making the issue go away is very weird... it can't be that the synchro is wired to the VDC?

[manda23]

do u mean VDC? or LSD as in mechanical LSD they put for racing cars?

crunching noise sounds like synchro problems, but turning off VDC making the issue go away is very weird... it can't be that the synchro is wired to the VDC?

Yes i mean the VDC button. Do you know when the car slip light comes on and stops power from going to the wheels. I think this button even when the wheels are spinning the power is still going to the wheels , kinda like a override switch.

What is synchro problems? My car seems to be ok now i might go for another run around and see what i can hear.

[rs73]

yeah I know what VDC is... I got mine kicked off a few times in the wet....

it does made grounching noise like rattling... the way it turn on brake on and off rapidly to limit the power going to certain wheel...

maybe it was vdc issue u're experiencing?

synchromesh is in the gearbox, the mechanism that allows you to shift gear smoothly, otherwise u'll be grinding the gear teeth all the time

[rs73]

VDC can have a false reading whenever it detects front and rear wheels are not rotating at the same speed, meaning there's a slip somewhere...

common issue is when you swap aftermarket rims and tyres, and the new tyres have the wrong size compared to OEM... e.g. too big or too small.

if your rims and tyres are stock, then must be something else that's causing the issue.

[manda23]

VDC can have a false reading whenever it detects front and rear wheels are not rotating at the same speed, meaning there's a slip somewhere...

common issue is when you swap aftermarket rims and tyres, and the new tyres have the wrong size compared to OEM... e.g. too big or too small.

if your rims and tyres are stock, then must be something else that's causing the issue.

Gear change is all good. And the problem is my IMPUL ecu doesn't have the dianogitics so how can the lube mobile guy or nissan find the fault??

I think what i need to know has something to do with the VDC . Like how does it stop power from getting to the wheels and how can i take it out. Maybe the sensor is playing up

[manda23]

VDC can have a false reading whenever it detects front and rear wheels are not rotating at the same speed, meaning there's a slip somewhere...

common issue is when you swap aftermarket rims and tyres, and the new tyres have the wrong size compared to OEM... e.g. too big or too small.

if your rims and tyres are stock, then must be something else that's causing the issue.

My tyres are 245/35/19 and 275/35/19 rear . So i think the problem is electrical not mechanical because it's not doing it all the time.

[manda23]

My tyres are 245/35/19 and 275/35/19 rear . So i think the problem is electrical not mechanical because it's not doing it all the time.

http://x.infinitihelp.com/forum/showthread...s-4279.html?amp;

[rs73]

same tyre size with mine...

if u got impul ecu then you'll probably on your own.

but might give it a try, some readings may still be available

[fcruz3r]

so you can't run staggered wheels on a V35??? bummer....that was my whole plan for the car!!!

[rs73]

you can, but you need to get your calculator out and calculate with a scientific mind, to make sure that your new tyre & rim combination does not change the front to back proportion of the stock rims & tyres...

similar cases to GTR owner who found when they run different size tyre front to back their AWD Atessa start playing up weirdly, thinking the car is loosing traction. they need to run all 4 tyres same size, or work out the proper proportion of width vs profile of the tyres to be all the same.

you know what I'm talking about, right? It's complicated but once you understand what tyre width and profile they're not hard to calculate.

[fcruz3r]

so whats the tolerance like? i mean in terms of % difference in diameter

would a 235/35 19 and 275/30 19 work???

Edited August 27, 2009 by fcruz3r

[rs73]

by law the circumference must not increase / decrease by 3%.

however it's not the tolerance, it's the proportion...

you can put a large truck rims and tyres as long as if you incraese the front size by 50%, the rear needs to increase by 50%.

i'll give you a formula....

235/35 19

235 is tyre width in mm (235mm)

35 is % of width indicating sidewall profile or height (235 x 35% = 82.25mm)

19 is rim diameter in inch (19 x 25.4mm = 482.6mm)

total tyre diameter: = (sidewall x 2) + rim diameter = (82.25 x 2) + 482.6 = 647.1mm

circumference = phi x diameter = 3.14*** x 647.1mm = 2031.89mm

you do the same for stock 225/45 18 for the front tyre you will get stock tyre diameter is 2071.45mm

legal requirement within 3% of 2071.45mm = between 2009.31mm to 2133.6mm so your 235/35 19 is not too small by law.

to ensure VDC don't play up, you check how much % less/more is the aftermarket tyre compared to stock:

(new tyre circ - stock tyre circ) / stock tyre circ *100 = (2031.89-2071.45)/2071.45*100 = -1.9%

you need to do the calc with rear tyre to see if your 275/30 19 at the back is as close as possible to -1.9% to rear oem 245/45 18...

I'm done enough calculating, so you do it yourself now.

[rs73]

I'll give you a hint.. it won't work... you will found out why after you do your calc...

[whtbox]

from Hyper rev the most popular Size in Japan for Staggered size is 245/35 19 and 275/35 19 which should disrupt the the VDC and closer to the speed read accuracy.

[scathing]

I took off in 1st it feeling like im towing something and again went into 2nd same thing no power and crunching noises.

I think what i need to know has something to do with the VDC . Like how does it stop power from getting to the wheels and how can i take it out.

VDC relies on the ABS sensors to tell the computer how fast each wheel is spinning. The other input into the VDC computer is a yaw sensor in the middle of the car. That detects accelerative forces on the car, so the computer can work out of the car's acceleration and turning rates line up with what the ABS sensors are telling the ECU as to how fast the wheels are spinning.

If that data does not correspond with "normal", it'll cut power to the engine by closing the throttle and it may grab the brakes as well.

You can unplug the VDC module. Your dash will light up like a Christmas tree and you'll lose the speedo/odo/ABS but the brakes will still work. If the car drives "normally" then you've found your culprit. Whether its the ABS or yaw sensor will require investigation.

Normally when the VDC detects a fault it'll just shut itself off as if you'd unplugged it as above. Its strange that the unit is just working overtime.

I rang paden at united at villawood he said mate thousand's if its a transmission problem.

Josh at Pro Concept has a spare 6 speed manual gearbox. I'm not sure how negotiable on that price he is, but you can give him a call. Find out if its necessary though. If turning off VDC stops it then its not a transmission issue.

Tell him that you're after the spare 350Z gearbox that was in Alan's car for a while.