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GT40-Steven
17-06-2009, 10:52 AM
The gearbox in my 99 VR4 have started to mak a strange little noise when shifting in automode. Best way I can describe it is a small "hoo". It only happens when cold, in automode and when shifting from 1st to 2nd + 2nd to 3rd. I also notice a slight slip when shifting from 2nd to 3rd when cold in automode.
As soon as I have driven 5min the sound and slip goes away.
ATF is amsoil since 2007. Fluid level and colour is OK.
No error codes shown (the N light flashes normally)
I did reset the ECU about 500miles or so ago since I had the battery disconnected then but this started about 100miles ago. Have not tried to reset the ECU again though since it feels more like something mechanical or hydrolic.

Any ideas?

Nick Mann
17-06-2009, 11:17 AM
Many VR4's have a sluggish 2-3 change when cold. I'm not sure I've heard the sound you are talking about though?

How have you been driving since the ECU reset? Heavy right foot driving after an ecu reset can make the box do some funny things.

GT40-Steven
17-06-2009, 01:53 PM
Just after the reset up till I thought the box had learned shifting I drove pretty "normal" that is no slamming the loud pedal. Been a mix of city driving and motorways. I have done some fairly heavy accellerations after the learning phase on the motorway lately though.
I'll try with a ECU reset again to see if it helps.
Have a hunch this is something mech or hydralic though. :uhoh:

Can you get airpockets in the gearbox? The noise sounds a but like a held back fart....

lazarus79
17-06-2009, 10:34 PM
i aint a legnum expert ( only had mine a year) but i am a mechanic! lol no airpockets but many auto boxes work better with just a litlle over the max mark on the dipstick of atf.
id recommend changin the oil again and starting from there if the reset dont work, oh and mine is sluggish 2-3rd when cold too

GT40-Steven
26-06-2009, 07:04 PM
Thanks guys for the input. I think I have solved the mystery. :)
The sound is coming from the AC pump! I never made the connection until I really started to think clear and conclude that the sound came from the right side of the car. It's just a freak thing that the rpm when it can be heard is just about when the gearbox normally shifts - about 3000rpm when I drive sensibly . Switching of the AC makes the noise go away. Probably need to replace the AC pump since it now have started to make more noises. At first I thought it was a turbo starting to give up but these noises also go away if I turn off the AC.

Anyway a lot cheaper then a gearbox rebuild!

I have reset the gearbox ECU again and now that one behaves a lot better. :)


EDIT: as far as I can see in caps the VR-4 do not share the AC compressor with the NA V6. Anyone know if it's just numbers and maybe the NA V6 AC compressor will work on the VR-4?

vr4-fan
29-06-2009, 05:18 AM
Thanks guys for the input. I think I have solved the mystery. :)
The sound is coming from the AC pump! I never made the connection until I really started to think clear and conclude that the sound came from the right side of the car. It's just a freak thing that the rpm when it can be heard is just about when the gearbox normally shifts - about 3000rpm when I drive sensibly . Switching of the AC makes the noise go away. Probably need to replace the AC pump since it now have started to make more noises. At first I thought it was a turbo starting to give up but these noises also go away if I turn off the AC.

Anyway a lot cheaper then a gearbox rebuild!

I have reset the gearbox ECU again and now that one behaves a lot better. :)


EDIT: as far as I can see in caps the VR-4 do not share the AC compressor with the NA V6. Anyone know if it's just numbers and maybe the NA V6 AC compressor will work on the VR-4?


how you reset the gearbox ecu???

Subaru ETA
29-06-2009, 06:52 AM
how you reset the gearbox ecu???


eerrrr...the same way you reset the engine ecu....

bradc
29-06-2009, 07:17 AM
The Aircon compressor was also changed pre and post facelift. I have one here from a 2001 car if you need it (and have a facelift!)

GT40-Steven
29-06-2009, 09:38 AM
Thanks bradc but I bet the shipping cost from NZ to Sweden will almost eat up the difference in buying a used and a new? PM me the price you want for it incl shipping to Sweden.

PS After the second reset the gearbox now shifts as it should *big sigh of releaf*