Major Automatic Transmission Issue - Gearbox going into limp mode

[pu-11-me]

Hey all,

4 days out from heading up to the Gold Coast and i now have a MAJOR gearbox issue.

I installed the trans cooler yesterday with no dramas, until today. I don't think it will be related though.

All is fine in all gears except 5th. When in 5th, it'll drive for a few seconds, then throws into third and locks there (whether in Tiptronic mode OR drive) and the neutral light starts flashing on the dash (signalling limp mode).

It does not give a diagnostic code.

ECU reset didn't help.

It didn't matter what speed i was travelling at, it still happened.

I left it for a couple of hours then came back and it stopped happening till the car warmed up and sure enough it came back to haunt me.

It is being sent in for Transmission service tomorrow, but i don't think the oil will be the problem.

I have posted here to help someone else -

There is 2 types of safety mode when the neutral light flashes....

One is overheated box (which i'm sure its not, but its a slower flashing) and the other is a sensor problem.......

Sensors it could be are -

Crank Angle Sensor (most likely)
Input Shaft Speed Sensor
Output Shaft Speed Sensor or
Solenoid Valve

Get local Mitsubishi to put the MUT II over it to get the trouble codes, it will tell you exactly which of these it is.

Problem is i'm fairly sure that none of these issues will be the problem either!!

PLEASE HELP!!

*prays he doesn't need a new transmission, but would secretly like to do a manual conversion, paid for under warranty

 

[bradc]

My guess is that unless you put new oil into the system after fitting the cooler you are now too low on oil in the trans. The cooler and lines might have a capacity of around 1 litre which is quite a bit to lose from the gearbox

 

[pu-11-me]

Cheers for the quick response Brad but it was a smidge overfull when we started and took 500mL when the job was complete so it has been topped up.... Which means its something more sinister

Hopefully the trans service tomorrow may shed some light or fix the issue, but the transmission was only serviced 8000km's ago so i'm a little doubtful that that'll fix it.....

 

[BuzzPuppy]

Is the trans cooler way too big?

Just an idea... someone may verify that there is a minimum temp that the ATF has to be at to function properly?

 

[pu-11-me]

Is the trans cooler way too big?

Just an idea... someone may verify that there is a minimum temp that the ATF has to be at to function properly?

Very true, could possibly make sense..... When in 5th i have to be travelling at speed, meaning it is getting cooled quicker and more efficiently

Only problem with this theory is that it only does it when the car warms up, as when its cold it doesn't do it

The other thing that has steered me away from this idea is that even using 4th in tiptronic mode and travelling the same speeds doesn't cause the issue. In saying that, the gears are spooling faster at the same speeds keeping the temp up slightly.

I may have to get ANOTHER gauge to sus this one out further to see if it is a box temp issue. At least this will be easy to see what happens in different gears temperature wise

The other thing i will get them to check tomorrow is that the oil is actually flowing through the cooler and rad

Cheers Gav

 

[pu-11-me]

I would also like to add that today was the first "warmish" day we have had here for a while at about 28 degrees and the car was driven in a manner some would say is not so tame.....

 

[Robotnik123]

Are you checking the transmission fluid levels in the right way? I.e. with the transmission hot, cycle thru all the gears a few times, pausing for a couple of seconds on each position and finally checking the level with the shifter in N and engine running?

If you don't do the check like that the levels could be all over the place and your transmission could be either over or under filled and you'd never know.

 

[pu-11-me]

Are you checking the transmission fluid levels in the right way? I.e. with the transmission hot, cycle thru all the gears a few times, pausing for a couple of seconds on each position and finally checking the level with the shifter in N and engine running?

If you don't do the check like that the levels could be all over the place and your transmission could be either over or under filled and you'd never know.

I've been checking when hot with the car in neutral.... It's getting serviced tomorrow anyway so i'm sure they'll make sure it is right then

I assume to check levels while in all gears i would need to be on a hoist? I didn't know that that could change the levels so its in the memory bank now. Do you know how being in different gears changes these levels?

Thanks for the advice Jan

 

[Robotnik123]

I've been checking when hot with the car in neutral.... It's getting serviced tomorrow anyway so i'm sure they'll make sure it is right then

I assume to check levels while in all gears i would need to be on a hoist? I didn't know that that could change the levels so its in the memory bank now. Do you know how being in different gears changes these levels?

Thanks for the advice Jan

I think I might have described things a bit better. What I meant was: before checking the ATF level on the dipstick, cycle thru all the gears, pausing for a couple of seconds on each. Go P-R-N-D-N-R-P-R-N-D-N. And with shifter in N and engine running check the dipstick. The engine should be nice and hot too (ie. like at least a 20 minute drive). The car needs to be on a flat surface, not a hoist. Obviously, engage the hand brake. And the gear you are in can effect levels - eg. if in P the fluid is routed differently to N.

Also check the level in N, not in any other gear.

 

[bradc]

Jan described it perfectly apart from making sure you put it into tip and go from 1st into 2nd then back into 1st, then neutral.

 

[pu-11-me]

That makes more sense now

That was done and all appeared to be OK but its going in for service in about an hour so i'll advise this afternoon how this went

 

[Robotnik123]

Jan described it perfectly apart from making sure you put it into tip and go from 1st into 2nd then back into 1st, then neutral.

I read on CVR4, that you don't go into tip and do 1-2-N. Am pretty sure it's not needed.

 

[pu-11-me]

Well no-one was even close

When they dumped the oil today the pulled chucks of metal from my box....

Apparently it is parts off some reverse gear cusioning band. It is also a common problem with Mitsi AT's

Thoughts are that chunks of this floating past sensors and through gears are causing my issues

Its gonna cost $2500 to fix it

And i have been advised to not leave town in it

 

[bradc]

Time for a manual conversion!

 

[pu-11-me]

Time for a manual conversion!

Tell me about it

 

[SiliconAngel]

I'm with Brad Dawso, spend half that on a MT from NZ and swap it yourself! :bigsmile:

 

[pu-11-me]

This information was found here -

Mitsubishi F4A51 Automatic Transmission Hazard Problem

I am writing on behalf of the issue concerning the safety and reliability of Mitsubishi and Dodge vehicles and their owners that contain the Mitsubishi F4A51 Automatic Transmission (2000-2005 V6 Eclipse, 2001-2005 V6 Stratus RT, 1997-2003 V6 Galant)

The main issue seems to be a manufacturing defect in the wave/cushion spring located in the transmission. Mitsubishi has designed the wave spring as a fragile two coil piece which has been known to repeatedly break causing catastrophic failure in the transmission. This in turn poses a threat on the driver and passengers. When this wave spring breaks, actual pieces of the wave spring make it through Mitsubishi%u2019s also faulty transmission filter and lodge themselves in the pump gear, causing the gear to actually break. After the pump gear has been broken inside the transmission, all forward and reverse gears immediately stop function and in most instances the vehicle shuts off. This could result in potential harm or even death of the driver and/or passenger as the vehicle loses all moving power which can cause an accident with other vehicles on the road. Mitsubishi has recently created an updated version of the wave spring without issuing a recall, which now is a one piece instead of the coil setup and has a less chance of breaking. To many Mitsubishi/Dodge owners this update was discovered after they have had their vehicle in a transmission shop with a hefty bill to pay even though it was Mitsubishi’s fault for engineering a faulty part in their transmission. All one person would need to find out about this issue is search the internet with the transmission code (F4A51) and this issue is well documented, even researched by Transmission Digest (a specialty magazine). Not only is this a large inconvenience to most, it is also a hazard to ones life. Mitsubishi should recall all vehicles which contain the F4A51 automatic transmission to perform the wave spring and filter update or reimburse those who have already had it done at their cost. This is an issue that needs to be addressed as if you own a vehicle with the F4A51 your vehicle WILL eventually need this repair, if you are still around to do it.

-------------------------------------------------------------------------------------------------------------------

The F4A51 is out of the Verada's and is almost the same as ours which is a W4A51

Auto drivers be wary of this as mine has just gone!!

 

[bradc]

You've got a W5A51, but they probably do the same thing

 

[pu-11-me]

You've got a W5A51, but they probably do the same thing

Lol.... I just read my bit at the bottom

I've fixed it now

 

[bradc]

Probably worth keeping the info there, it might be true for our gearboxes too