Help Needed, A/t - Wiring.

[Stagea Denmark]

Hi guys.

I have a Stagea, imported from Japan 8 month ago, and i have some problems with my car, and i am the one and only owner of a Stagea in Denmark, nobody to ask.!

My biggest problem is my auto gearbox, a guy told me it have 4½ gear, when i drive at 90-110 km/h, it suddently goes down i 3. gear and back again, it don't do this every day, only sometimes, it jump from 4. to top-gear many times every day, and i hate this. Sometimes when it goes a little bit faster 169 km/h, it jumps down i 3. gear, and thats very bad for the engine, the rpm goes from 4000-6000 and my heart stops for a few seconds.

I am pretty sure it is a electrical problem, but i don't know where to look, i diden't get a workshop, or handbook when i imported this car.

Edited January 15, 2008 by Stagea Denmark

[Stinky Rooster]

need more info!!!

what series? (this will make a difference)

If S2 is it triptronic?

is the car 2wd or 4wd?

BTW, don't fear the kickdown - the RB25 will handle 6000rpm no worries, even std. I probably wouldn't do it all the time, but now and again won't hurt it.

[Tangles]

the auto could simply need a service?

[leetom]

you sure it's the auto and not just boost, is your selector display showing what gear it's in?

[pixel8r]

The stagea/skyline auto boxes are quite touchy with gearchanges. I think they do "learn" your driving style in the sense that it will try to work out when you want to shift up a gear and when you're just easing the throttle down a bit and want to stay in the same gear...

I find the kickdown very quick and only a small foot movement is required to kick it back a gear, but this is one thing I really like about Nissan autos, compared to other manufacturers (ie. ford/holden over here). It gives more of a sports feel to the gearbox rather than the slushiness that exists in our locally made cars here.

I've got a shift kit fitted as well for the same reason - just to improve the snappiness and response of the gearbox.

Not sure how to reduce this behaviour though. Its possible from what you've said that you do have an electrical problem with your gearbox...but if it only does this while accelerating and not while cruising then dont worry about it.

4th gear is more of a "reduction gear" anyway and is really only there for fuel economy while just cruising along (at any speed, although over 80km/h it will attempt to lock up the torque converter, dropping the revs even further and saving a bit more on fuel). What this means is as soon as you want to do any accelerating, it will likely shift back to 3rd if it can (depending on your speed) in order to get more power/torque.

The shift points in an auto are usually designed around where the engine makes the most torque, so when accelerating hard, it will try to maximise torque, but if you only accelerate mildly, it will probably just get to top gear asap to minimize engine revs etc.

Hope this has helped a little.

[Stagea Denmark]

Hi guys.

Thanks for the replys.

I am noth sure what model my car is, i found a treat yersteday, where all the extra features was listed on all the differened Stageas, doubbel sunroof, electrical reardoor, leather seats ect., i have all these things i my car, i am pretty sure my car is a 25X, the engine is the RB25DE.

All these problems i have witth my gearbox, is happen when i am crusing, the torgue converter let the rpm go up and down with 3-400 rpm all the time, thats between 90-110 km/h on the highway, and i am noth pussing harder on the truttle.

When it goes down i 3. gear, it happen 3-4 times every week, sometimes it stays in 3 gear, even with speed over 120 km/h, up to 160 km/h, then i try to lift my food on the truttle untill it goes back in the higher gear, even when i push the kickdown buttom, and let go again, nothings happen, when it goes down in 3. gear and stay there for at few minuts, and i push this kickdown buttom, is it like i dident push the buttom, the rpm is the same.

My biggest problem is, that i put in a RB25DET Neo engine in 2 weeks, with a lot of upgrades and 500-550 hp, i can choose to change the gearbox as well, but it will be stupid, if it is a electrical problem, then i still have the same problem, and now more power.!!

[STAG250]

My biggest problem is, that i put in a RB25DET Neo engine in 2 weeks, with a lot of upgrades and 500-550 hp, i can choose to change the gearbox as well, but it will be stupid, if it is a electrical problem, then i still have the same problem, and now more power.!!

er I wouldn't think a standard 25x det gearbox would handle that much oomph

[Stinky Rooster]

er I wouldn't think a standard 25x det gearbox would handle that much oomph

+1

and its a RB25DE box, not a DET.....

Drop your new motor in, and when the box lets go in its first week, then do a manual conversion and you will be good to go! If your car is a S1 and the problem is electrical, then changing the box will make a difference - the ecu doesn't control the gearbox.

[Stagea Denmark]

+1

and its a RB25DE box, not a DET.....

Drop your new motor in, and when the box lets go in its first week, then do a manual conversion and you will be good to go! If your car is a S1 and the problem is electrical, then changing the box will make a difference - the ecu doesn't control the gearbox.

I have no idear what kind of gearbox i have, but when i look around in my car, it look like it have been a manuel car before, but i love automatic gearboxes, because you dont get the turbo-lagg, like you does on a manuel gearbox.

Ps. I have a 5 speed manuel gearbox and pedals from my frontcut.

[STAG250]

but i love automatic gearboxes, because you dont get the turbo-lagg, like you does on a manuel gearbox.

I get turbo lag on my vq25det

yeah stinky I got confuzzled

[Stagea Denmark]

I get turbo lag on my vq25det

yeah stinky I got confuzzled

Yes thats noth funny if yor are in a hurry, like on quartmiles tracks.

A big turbo, boost at 4-4200 rpm, at 2300-2500 rpm add 30-50 hp of NOS, thats give a kick.

[pixel8r]

I have no idear what kind of gearbox i have, but when i look around in my car, it look like it have been a manuel car before, but i love automatic gearboxes, because you dont get the turbo-lagg, like you does on a manuel gearbox.

Ps. I have a 5 speed manuel gearbox and pedals from my frontcut.

You still get turbo lag, just that its less likely to drop off boost between gear changes, which is only important at the drag strip really. I'd guess in day-to-day driving, the manual would feel a lot more responsive.

I like my autos purely for convenience. No manual gear changing(duh), and no clutch. Maybe I'm just lazy...

I wouldn't be putting a stock auto box behind that much power either...especially the DE auto box. Plus I'd suggest that a 500hp RB25DET would be laggy, but it probably depends how much money's gone into it?

Hope it all goes well anyhow...