overdrive ??

[Kelly&Ben]

does the auto box have overdrive if its in drive position? i reset the ecu's by having no battery on for ages on weekend. notived today as its in 5th it sounds like its changng gear, revs drop down to like 1500 rpm but it still shows being in 5th? if i put the pedal down a bit more it would sound and act like changing down a gear. revs back up to like 2500 but still showing in 5th?

[miller]

ASFAIK its got a low and high range in 5th gear.


But i could be talking complete tosh. i do know what your describing though!

[elnevio]

Sounds like the torque converter doing its business normally to me! Don't think it locks until just under about 3,000 rpm, IIRC.

[Nick Mann]

What you are describing is a torque converter lock up. (The same system that can cause judder in unloved boxes.)

The TC locks up when cruising in 4th or 5th gear. Asking for acceleration will release the TC lock up, allowing the TC to slip. So the revs can rise even though the gear hasn't changed. If you then ease of the accelerator a bit you'll notice the revs creep down again even though your speed doesn't. Thats the lock up re-engaging. Obviously, asking for a lot of acceleration will result in the gears changing down too.

[miller]

there ya go, i was talking tosh!

[Kelly&Ben]

What you are describing is a torque converter lock up. (The same system that can cause judder in unloved boxes.)

The TC locks up when cruising in 4th or 5th gear. Asking for acceleration will release the TC lock up, allowing the TC to slip. So the revs can rise even though the gear hasn't changed. If you then ease of the accelerator a bit you'll notice the revs creep down again even though your speed doesn't. Thats the lock up re-engaging. Obviously, asking for a lot of acceleration will result in the gears changing down too.

Well before i reset the ecu's it use to judder/ grabs hard (only sometimes) into 3rd gear so i thought maybe will help it out. seems a bit better but i guess its still in learning too at the mo, any idea/reasons? always holds fine, drives fine etc.. just did that in 2nd-3rd gear change

[elnevio]

Maybe just needed a reset after all, but the juddering would be pointing towards deteriorating fluid, IMO. What ATF is in there now, how long has it been in, and what condition is it in (check colour)?

[Kelly&Ben]

where do ya check it to on em?

dont think its been changed too long ago. i have receipts off previous owner and ATF fluid is meant to be almost life time isnt it? so should think its ok?

[Confused]

Down between the battery and the air filter is a dipstick.

Take this out, and smear some of the fluid onto a sheet of plain white A4 paper.

If it's been recently changed, it should be bright, blood-red.

If it's brown, it's starting to get burnt.

Check the service history - and hopefully it's got exactly what kind of ATF has been put into it. It'd better say Mitsubishi SP-II/SP-III or Amsoil Universal ATF. If it's got anything relating to "Dexron" then you need a full flush ASAP!

[Kelly&Ben]

cool i'll check it when the rain stops. lol

in my receipts i have one for last may for amsoil ATF

[elnevio]

in my receipts i have one for last may for amsoil ATF
That is encouraging. How much (in quantity) though? A gearbox ATF change should be up to 12 L. If it's just 5L, then it might only have been the sump that was changed, i.e. about half of the total fluid, so you get new and oil fluid mixing.

However, it was shaun1978's old car, so I'd be pretty certain that a full flush was done!

Check the fluid level (engine running, cycle through the gears P > N > D > 1 > 2 > 1 > D > N, leave in neutral with engine running - I often do this when I get home so the fluid's nice and warm!) as the boxes can be quite sensitive. Take a few readings, as the dipstick design is pants.

[Turbo_Steve]

ATF fluid is meant to be almost life time isnt it

Not in these boxes, mate. Mitsubishi reccomend 45,000 mile changes, I think, but most people have found that it heavy usage (eg Trackday, towing) can get it to deteriorate quicker than that. I use amsoil in mine, and it seems to suddenly gobble it all up every 10,000miles or so. I top it up, and it's fine, but I will be completely draining and examining the fluid carefully in 10,000 miles time.

[shaun1978]

That is encouraging. How much (in quantity) though? A gearbox ATF change should be up to 12 L. If it's just 5L, then it might only have been the sump that was changed, i.e. about half of the total fluid, so you get new and oil fluid mixing.

However, it was shaun1978's old car, so I'd be pretty certain that a full flush was done!

Check the fluid level (engine running, cycle through the gears P > N > D > 1 > 2 > 1 > D > N, leave in neutral with engine running - I often do this when I get home so the fluid's nice and warm!) as the boxes can be quite sensitive. Take a few readings, as the dipstick design is pants.
Yup 15L of amsoils finest was used to do a full flush....

[Kelly&Ben]

cool thanks shaun, good to know! does seem a lot better now its been reset. i'm sure i read somewhere ages ago someone had a similar problem and it was only when they put a later ecu into their car?

[Kelly&Ben]

speakin to my mate he says its because the auto ecu is not calibrated to the new later edition ecu so a calibration form mitsi or a matching later auto ecu should do the trick

[orionn2o]

Have you got a different ecu from the standard one in there then?

[Davezj]

speakin to my mate he says its because the auto ecu is not calibrated to the new later edition ecu so a calibration form mitsi or a matching later auto ecu should do the trick

this dosen't make sense, are you talking about different ecu (engine and auto) or just auto ones or is it the boxes that don't match the ecu.

[Kelly&Ben]

the car has a later engine ecu but still the standard (not later) auto ecu. he said he gets it quite often (works for toyota) the auto ecu's just need recalibrating and it wont do the weird change into 3rd

[Subaru ETA]

you cant do PCM upgrades on mitsis tho....

[bradc]

Nahh he is talking complete crap. Resetting the ecu will make the auto feel a bit different for a little while, nothing to worry about at all.

[Subaru ETA]

on toyotas, mazdas etc what you mate is talking about is correct, but not for our cars.