Calling all wisdom folk.

Got a bit of a problem with the 4 Speed auto in our TR, has happened twice, once about 3 weeks ago, and again on the way out tonight. Basically, what happens is when the auto box reaches for 3rd (I think thats what its doing), it basically disengages all gears and just revs itself in neutral until I lift off totally and wait for it to drop back to idle, when I presume it engages 4th and away we go.

First time round I figured it must have just slipped or something, no big deal you know, but now its done it twice its got me a little worried. I'm not 100% on the last time the tranny was serviced (wasn't that long ago though, would have been in the last 15k's I think), so should I book her in for a tranny service, or is it something more major, like the transmission on its way out? Its done about 187k's, and its the original tranny.

Thanks guys n gals :)

torque convertor????

torque convertor????
Come again?

have you tried resetting the ecu

PM Magna_buff, he's the resident auto trans expert.

Sounds to me like your box is ****ed... Usually third gear stays and second gear dies along with overdrive.

have you tried resetting the ecu
How do I do that? Sorry I'm no technical buff with these things haha.


PM Magna_buff, he's the resident auto trans expert.

Sounds to me like your box is ****ed... Usually third gear stays and second gear dies along with overdrive.
I'll give Magna_buff a pm later today then perhaps, its been working fine today, put it under a bit of load a few times today and it coped fine with acceleration...got me totally stumped.

Thanks magna_buff :)

Its definitely when it engages third, not overdrive, I've positive on that, still the same deal though?

According to the fault diagnosis chart in the factory service manual, failure to shift 2 to 3 may be due to:
* Worn inside diameter of front clutch retainer
* Malfunction of valve body (sticking valve, working cavity, adjustment etc.)
* Malfunction of front clutch or piston
* PCSV (Pressure Control Solenoid Valve) damaged or disconnected wiring (valve open)
or
* Malfunction of Transmission Control Unit

I'm definitely no expert but if it is only happening occasionally, a sticking valve or solenoid could account for it (or possibly a poor connection or damaged wiring to the PCSV).

i'm sorry... when i read the thread header i thought the thread was about this:

http://www2.b3ta.com/bigquiz/trannyorgranny/

:)

Thanks guys, I'll get the mechanic to check it all out next time it does in.

Thanks magna_buff :)

Its definitely when it engages third, not overdrive, I've positive on that, still the same deal though?

you can check the solinoids and TCU first
the torque converter stall test

then drain the oil take the pan off and the oil filter

if there is a lot of brown material or metal to be found there ...the box has to come out

you will need to decide
a partial rebuild
a second hand auto
or a full rebuild

you may have broken cogs or bearings in the main cluster of cogs (rare)
one box even had a broken main shaft
but that wont be known till strip down

if there is a lot of brown material or metal to be found there ...the box has to come out

you will need to decide
a partial rebuild
a second hand auto
or a full rebuild



I'll give you some rough estimates

a partial rebuild = $500 - $1000 (depending on problem, if its the gears you will need full)
a second hand auto $200 - $700+ (Depends on place bought from)
or a full rebuild $1200 - $2000+ (Depends on place)

Oh yeah, most would suggest manual change-over for the above prices.

Before worrying do as magnabuff has said, flush, filter, etc

i'm sorry... when i read the thread header i thought the thread was about this:

http://www2.b3ta.com/bigquiz/trannyorgranny/

:)


yep Lugo, watch out for those trannies, remember, before jumping in the sack, make sure she doesnt have one :bowrofl: :bowrofl:

I'll give you some rough estimates

a partial rebuild = $500 - $1000 (depending on problem, if its the gears you will need full)
a second hand auto $200 - $700+ (Depends on place bought from)
or a full rebuild $1200 - $2000+ (Depends on place)

Oh yeah, most would suggest manual change-over for the above prices.

Before worrying do as magnabuff has said, flush, filter, etc
Ouch :shock: Think if thats the case it might be the time to update.....:redface:

Yeah bout the manual conversion, I'm all for that....but mum drives the car too...reckon I could make her drive a manual? bahahaha....never. Those 2nd hand auto prices, obviously thats not including actually getting it fitted aye?


you can check the solinoids and TCU first
the torque converter stall test

then drain the oil take the pan off and the oil filter

if there is a lot of brown material or metal to be found there ...the box has to come out

you will need to decide
a partial rebuild
a second hand auto
or a full rebuild

you may have broken cogs or bearings in the main cluster of cogs (rare)
one box even had a broken main shaft
but that wont be known till strip down

Whats the forum sign for that went right over my head? I don't know what a solinoid or a TCU is...Talk to me in stupid English hahaha


yep Lugo, watch out for those trannies, remember, before jumping in the sack, make sure she doesnt have one :bowrofl: :bowrofl:
:bowrofl: I'll keep that in mind....

Whats the forum sign for that went right over my head? I don't know what a solinoid or a TCU is...Talk to me in stupid English hahaha

TCU is the transaxle control unit, basically reads in the current RPMs of the engine, fluid temperature, etc... oh, and determines when it's time to shift up and shift down. Solenoids are what it's connected to, the TCU fires off a signal to the solenoid that then physically moves it in to gear.

Maybe, I think. lol

I'd get it booked in for even diagnostics, could be something simple because at the moment the problem doesn't seem to be occuring very often. Leaving it may result in some serious damage in the long run though.

Here's hoping it's nothing major.

Ah ha.....I'll let the mechanic work it out lol....

Its probably my fault you know, don't tell mum that though hahah....before I drove the car it rarely saw the high end of 2 grand......sees 4 nearly all the time now lol...probably put a little too much stress on her :cry:

Ah well, I wouldn't blame yourself really, the Magna automatics are prone to failure. Sometimes it's just the TCU wearing from age, if you're lucky this will be the case and another one will solve your problems. Otherwise it's probably just wear and tear of the physical components. Best to get it serviced (preferably by a competent auto specialist, as I learned the hard way :doubt:).

For the record, the most common problem with the TCU's are leaking capacitors, which in turn can do as little damage as just a worn component, all the way up to leaking completely and corroding surrounding components. I'm rebuilding my old TCU at the moment, needs new caps all around but doesn't seem to have corroded too badly.

Ah well, I wouldn't blame yourself really, the Magna automatics are prone to failure.


my bro's ks with near 400000km's on original transmission with no mishaps says otherwise. ****ing well made.

Treated harshly but serviced.

Ah ha.....I'll let the mechanic work it out lol....

Its probably my fault you know, don't tell mum that though hahah....before I drove the car it rarely saw the high end of 2 grand......sees 4 nearly all the time now lol...probably put a little too much stress on her :cry:

my gearbox is still there buddy. going strong, so you've got nothing to worry about (coming from a guy who uses "active select" in a new calais and doesn't shift until 5500-6000rpmlol)

simpified

they open and close like valves allowoing automatic oil into the valve box chambers

under pressure and re-nter the top part of the box to operate and lubricate the main

components

Hey Buff, whilst we're on trannys, got anything that'll seal a flood? (This isn't a leak. This is at least litre of ATF every 5,000km! Even the N13 Pulsar doesn't leak that much) Still not able to discern where it's coming from, as I'm STILL cleaning the crap off.

pm you gav

i had the same problem, couldnt work out why. ended up being the overdrive gear was not functioning, so got a quote from a mechanic.... 300bucks....went to wreakers, found a 2nd hand one for 40bucks and all works again no worries!.

i had the same problem, couldnt work out why. ended up being the overdrive gear was not functioning, so got a quote from a mechanic.... 300bucks....went to wreakers, found a 2nd hand one for 40bucks and all works again no worries!.
Hmm ok....its not the overdrive though, because its happening during firm acceleration around the 40-50km/h mark, the car wouldn't be engaging overdrive in the circumstances either time. If I recall correctly o/d was turned off the first time it occurred anyhow.

i'd reccomend gettin it checked asap i've had 2 trannys die... 1 in each of my cars it's not much fun when ya cant get where u need to go!