Transmission Wont Shift.

[Jamie-b]

Hi,
Ive got an AU sedan with 31x,xxx Km. It was just bought to drive to and from work to avoid getting into my other cars dirty, so it is a bit rough..

After owning it for a while i realized it was starting to develop some problems with the transmission, when selecting and gear it would take 1-2 seconds to feel the 'clunk' into gear,then eventually it would free when shifting up gears for a split second. The problem kept getting worse and occasionally you would need to give it a little rev for it to engage gears.
I lent the car to a friend, and got a phone call from him saying the car wouldn't move (would just rev).

I got it home, and dropped the belly off the transmission, changed the filter and refilled it. The problem seemed to get better, but it was still there.

Current Problem
Now the problem has started getting much worse, but it is only intermittent.
When i select Reverse sometimes its fine, but other times the car wont move unless i rev it, it feels under load, and as soon as i stop revving , the car stops instantly. Sort of feels as if it is engaging a forward gear too?

and sometimes when i select a forward gear it will shudder at first as if the gear is only half engaged, but then feels normal after 1-2 seconds.

But the most concerning issue is when driving it cant seem to make up what gear it wants. i will be accelerating lightly but the car will be reeving hard, and will only up shift when there is virtually no throttle, and as soon as i touch it, it will down shift again.

I also tried toggling the 'economy/power' button but it is stuck (not sure what mode) not sure if this would effect it.

Also if i have the car running with the headlights on and turn the ignition off, the car will keep running until i turn the lights off. But this will only happen if a drive dear has been selected since the car was started. (Wont happen if i keep the car in P from staring)

Long read but help would be appreciated!

[mik]

g`day mate , the motor staying running with lights and in gear thing, that sounds really weird, never heard it mentioned on the forums before, i`m not a lot of help with the auto either i`m afraid, with the engine, lights on and auto in gear and motor staying running happening, one wonders if there`s any electrical gremlin causing the auto to go haywire as well?
on the other hand it`s done 310,000 k`s it might be getting a bit tired, as far as the auto goes are you sure it`s got enough fluid in it? i`m thinking it may have had a leak before and been playing up? not knowing how much you know about auto`s, a novice might fill it up once without starting the engine running through the gears and topping it up again, etc, not calling you novice but it don`t know if you`ve done it before.
plenty of clever dudes here, someone might have a bit more of a clue than i , good luck.

[Maka]

G'day Jamie, clutch pack in your auto sounds like its starting let go, speedo sensor could be also malfunctioning or tps. When my transmission let go years ago it had trouble moving off- delay when shifting to reverse or 1st gear and eventually wouldnt go into reverse at all, took it to the local a/t expert, dropped the pan, cut the filter open and it was full of clutch plate material. The thing with btr's is not to let them get hot. If youve still got the filter you've just replaced cut it open & see whats in it. Google your problem and see what comes up. Take it to your local a/t expert for an enlightened opinion asap! Good luck

cheers, Maka

[Mr Hardware]

310k is about new trans time. we'd get only a tad more than that out of the cab autos and they were serviced every 40k (the trans, that is)

[Jamie-b]

Thanks for the help guys,
I did recheck fluid levels and all is good in that area.

When i dropped the pan off for the service the oil was pretty bad, Very dark, so there is a good chance the clutch packs are gone,

I guess it might be time for another tranny, What should i be looking at for an auto from the wreckers? (Rebuild/reco wouldnt be viable) Or buying a wrecked car from pickles got parts might be the go..

When i was driving it today i thought possibility of TPS, is there a fault code check i can do that could confirm any suspicions?

And i think she might have some electrical gremlins, noticed today that the park lights are coming on with brake lights :s
And the 3rd Brake light is on with headlights :/

[XRGhia]

I'd be checking your two main brake lights, sounds like one of them has a single filament globe instead of a dual filament globe...

[Jamie-b]

Checked the TPS Voltage and it seems ok, (.75v closed, 4.4v open)
does this rule out the tps? (downshifting at the slightest throttle)
Somebody at work mentioned the 'shift card' could need adjusting as sometimes when you select gear it's as if its stuck between 2 (Mostly when selecting reverse)

[Evgeni]

Originally Posted by Jamie-b

Checked the TPS Voltage and it seems ok, (.75v closed, 4.4v open)
does this rule out the tps? (downshifting at the slightest throttle)
Somebody at work mentioned the 'shift card' could need adjusting as sometimes when you select gear it's as if its stuck between 2 (Mostly when selecting reverse)

Your tps voltage is within range. What you need to look for is drop outs or voltage moving below 750mv on a snap throttle and coming back to 750mv. Good if you have a graphing multimeter, but, if you run the meter back to the drivers seat and press the accelerator in a 'constant' manner, you will know if the voltage doesn't correspond.
With your lights, I would start by looking at the ground connections and what condition they are in. You can access a wiring diagram via this website which will help.
What was the ground voltage reading on the tps? Under 100mv? A couple of sensors share this ground, so anything more and you could be onto something.

[Jamie-b]

Checked for Drop out's, spikes etc.. and it seems to steadily increase in proportion to the throttle.
Not sure what you mean by ground voltage, but from the middle pin to Neg battery post is .8v and from bottom pin to neg battery post is .07 v

Spot on with the lights, single filament bulbs were the culprit.

[Evgeni]

Originally Posted by Jamie-b

Checked for Drop out's, spikes etc.. and it seems to steadily increase in proportion to the throttle.
Not sure what you mean by ground voltage, but from the middle pin to Neg battery post is .8v and from bottom pin to neg battery post is .07 v

Spot on with the lights, single filament bulbs were the culprit.

Probably a misleading term - "ground voltage". Apologies.
That bottom pin is the ground wire - so if there is a significant reading on it, the sensor will send a false signal back to the pcm.
With those figures, your TPS is solid and can be ruled out at least.

[Jamie-b]

Looks like ill chuck another transmission at it and see how it goes.
Fuel consumption is up the crap, 25lt per 100km (Driving conservatively & i dont live in the city)