R34 Tiptronic Transmission Problems

[john-e boi]

Is it a GTt or 25GT?

Have the solenoids been replaced with brand new items or tested ones? The reason I ask is the ones out of my old car that were dodgy always worked fine at room temp, tested fine etc etc, but when at operating temp they went open-circuit and threw the code.

When the ENG A/T CONTROL fuses go, lots of funny things happen, nerver seen it throw a solenoid code, normally just makes the car stall and drive like shit.

its a GTt

yeah i've heard about room temp problem so i've changed to brand new solenoids.

kind of hit a brick wall and ran out of ideas. no one has a clue whats wrong. i know there can be millions of reasons causing it, but if you guys can give me possible causes that would be great. solenoids been changed, ecu swapped over, wiring checked, gearbox is fine no burning smell inside nor does it slip during the few seconds it does work when first start the car and shifting gears normally. all thats done to gearbox is tranny oil cooler, 2800/3000rpm hi-stall from MV and stage 2 shift kit also from MV. any help would be greatly appreciated.

just curious. how much am i looking at for a manual conversion. got quoted $3.5k does that sound alright?

[666DAN]

Has anyone checked the 'Shift Control Unit' in the drivers side kick panel (small metal box closest to the door)? This is the thing that gets the messages from the TCM built into the ECU, then fires the shift signals to the solenoids, it may be a loose plug or worse case, buggered.

If you can take it out, post it to me and I'll check it in my car if you like?

[john-e boi]

Has anyone checked the 'Shift Control Unit' in the drivers side kick panel (small metal box closest to the door)? This is the thing that gets the messages from the TCM built into the ECU, then fires the shift signals to the solenoids, it may be a loose plug or worse case, buggered.

If you can take it out, post it to me and I'll check it in my car if you like?

thats been replaced too. thanks for the help dude.

[Dal34]

Glad I converted her to manual...

[john-e boi]

just curious, would an engine component cause this problem. some might not be running correctly causing the car to run into this mode? cause its really heading towards a brick wall with no idea where to go.

[llama_au]

My car started doing it this morning, only as it got closer to operating temperature. Noticed when taking off from a standing start it was ridiculously hard to get moving. Tried tiptronic mode, no go, wouldn't respond to my changes at all. Eventually deduced it was stuck in third. Turned the car off, started it again and the A/T warning light on the dash flashed but it drove okay. Started it again later in the day, again drove fine for about 15 mins, pulled up to a set of lights - stuck in third again. Turn the car off and then on again, A/T warning light on the dash flashing.

It's really sudden, there was nothing leading up to this happening.

Reading this thread, I'm getting worried as not everyone's sorted their problems out...

[john-e boi]

well my car has definantly hit a brick wall. cant seem to find the problem what so ever. the gearbox is in working order, but the ecu is finding some form fault somewhere. theres another r34 at the place at the moment so the guy is going to swap over a few other items see if anything solves the problem. otherwise manual conversion that i seriously rather not do. a stupid problem with what seems to be unsolvable problem.

[llama_au]

Sorry to hear.

Mine's shift solenoids, they're getting replaced this weekend. It was an expense I didn't need right now.

[john-e boi]

hope all works well for you dude.

mine came up as a shift solenoid problem. its been replaced along with a whole bunch of other stuff such as shift control unit and other solenoids. hasnt solved the problem. last resort is manual conversion. and that might come as early as next week. car has been off the road for over 2 months now. depressing

[llama_au]

I'll have my fingers crossed.

[iseekool]

well my car has definantly hit a brick wall. cant seem to find the problem what so ever. the gearbox is in working order, but the ecu is finding some form fault somewhere. theres another r34 at the place at the moment so the guy is going to swap over a few other items see if anything solves the problem. otherwise manual conversion that i seriously rather not do. a stupid problem with what seems to be unsolvable problem.

Hey mate - check all your grounding - make sure they are clean and firmly in place, my mates 180sx had a similar issue (I know its a different car - but from memory the auto trans is from the same family) with the trans always going into limp mode intermittently. My mate brought his car to an auto electrician for another un-related issue and the auto elec found out one of the grounding wires was not connected/possibly came loose. Since then no trans issues with what so ever, best 5 minutes spent....

Also check for chaffed wires, which could cause shorting.

Hope this helps.

[llama_au]

F*ck, just my luck - Nissan have none in stock. 2 weeks lead time from Japan. Car will have been off the road for 3 weeks by the time they arrive.

[john-e boi]

Hey mate - check all your grounding - make sure they are clean and firmly in place, my mates 180sx had a similar issue (I know its a different car - but from memory the auto trans is from the same family) with the trans always going into limp mode intermittently. My mate brought his car to an auto electrician for another un-related issue and the auto elec found out one of the grounding wires was not connected/possibly came loose. Since then no trans issues with what so ever, best 5 minutes spent....

Also check for chaffed wires, which could cause shorting.

Hope this helps.

thanks for the input dude. but car going in on friday for the manual conversion. so this will no longer be a problem. hope all you guys dont have to go through what i had to with the car being off the road for 2months+ and ending up doing a manual conversion that takes less than a week.

[iseekool]

Does this issue happen to the non-turbo R34s?

Reading this thread has me wanting to buy a set of solenoids "just in case"

[666DAN]

Yep happens to the N/A's as well, was my first encounter with the issue in my '99 model 25GT back in 2002

[iseekool]

^ I might buy some soon and store them. My car has now done 115,000km - I bought the car at 100,000km. I've changed trans fluid (Transmax Z) not too long ago *fingers crossed* this would delay them from failing soon.

[llama_au]

Mine has happened at ~132,000. I bought the car at ~117,000.

[llama_au]

Back and driving perfectly. $698 later

[iseekool]

Back and driving perfectly. $698 later

Any difference in shift quality/performance?

[llama_au]

The shifts feel a smidge harder at low speed, but that could just be my imagination.