Occasional trans hard down shift and AT oil temp light

[davidschaffer]

I have a 2000 outback with a 2.2 from a 98 Impreza.  Every once in a while and with no apparent rhyme or reason, when coming to a stop the trans will slam into probably 1st and the AT oil temp light comes on.  It has happened maybe 5 times in the past few months.  After the first time i had the trans fluid changed and a new filter put on.  The fluid was and is very clean.  Any ideas as to what is going on?  Also, lately I have noticed a loud humming noise coming from the  air intake.  If I unlatch the filter box it is really loud.  This is my wifes car so I am not in tune with it but it seems to me to be a new noise.  Thanks for any info y'all may have.

 

[Fairtax4me]

If the AT temp light comes on it usually means there is a code.

Search for the method to get TCU codes for your year. Its a fairly simple process, I just don't know it off the top of my head.

 

Also check the large connector(s) for the transmission wiring harness.

 

Humming from the air box could be because it isn't fit together properly at the bottom.

[davidschaffer]

If the AT temp light comes on it usually means there is a code.

Search for the method to get TCU codes for your year. Its a fairly simple process, I just don't know it off the top of my head.

 

Also check the large connector(s) for the transmission wiring harness.

 

Humming from the air box could be because it isn't fit together properly at the bottom.

Thanks for the reply.  Could the large connectors cause the hard down shift and then the AT light?  The humming gets louder if I unbuckle the air box, maybe thats just the way this motor sounds.

[1 Lucky Texan]

can the IACV buzz?

[TOONGA]

Not too sure about the auto transmission I would be getting a good mechanic to look at it.

 

As for the humming noise there is a part of the airbox in the guard of nearly all subarus with fuel injection. if this isn't in place of the part has been removed to accomdate the different engines air box then it will hum. The hum isn't a problem just annoying.

 

TOONGA

[shoebee2]

The module for the downshift, usually located on the lower side of the tranny by the pan will cause this behavior. Lots,of times they get bunked up by a leaky trains pan.

 

My experience with auto transmit is otr trucks and Alison transmissions. They all work pretty much the same. What you describe sounds like a valve body issue more that a control issue. Just hard shifting from 2nd to 1st points to modulator. If you have a spare tranny swap it out and see if it helps/makes it worse.

 

Sometimes the pickup screen can get clogged by gunk in suck a way as to starve oil return during downshift. That will maintain pressure in the galleys when it should be bleeding off to allow shifting. Eventually the pressure overrides the clogged screen and, bam, shift.

 

A lot of times having the tranny back flushed at a shop will take care of a lot,of weird shift issues.

[davidschaffer]

So it's been quite some time since the trans has clunked into gear, but the delay in going into drive has gotten worse. I changed the fluid/filter and exchanged a quart of tranny flyid for stop slip but it is not helping. Should I add more stop slip? How long until it just stops working? The car is probably not worth a rebuilt tranny.

[1 Lucky Texan]

I have read that folks do seem to have to refresh the additive - but usually only every year or 2?

 

could soon be time to seek other options.

[johnceggleston]

if the ''slip stop'' you are using is not TRANS-X

you are not using the right stuff.

it should start helping almost immediately.

but id does need to be ''refreshed'' about every 12 months.

 

 

I have a 2000 outback with a 2.2 from a 98 Impreza.

i would love to know how this was accomplished,

a phase 1 engine in a phase 2 car?????

did you do the swap?

did you buy it this way?

 

 

if the AT Temp light is flashing there is a code to be read.

[davidschaffer]

 

if the ''slip stop'' you are using is not TRANS-X

you are not using the right stuff.

it should start helping almost immediately.

but id does need to be ''refreshed'' about every 12 months.

 

i would love to know how this was accomplished,

a phase 1 engine in a phase 2 car?????

did you do the swap?

did you buy it this way?

 

 

if the AT Temp light is flashing there is a code to be read.

I did use Trans x. It seemed to hell at first but only for a few weeks. I will try another bottle. I did not do the swap, bought it from a Subaru mechanic.

Edited August 5, 2015 by davidschaffer

[Fairtax4me]

i would love to know how this was accomplished,

a phase 1 engine in a phase 2 car?????

did you do the swap?

did you buy it this way?

 

98 short block between 00 heads. Only easy way to make it work.

 

If Trans-x isn't working, the days are numbered for that transmission. Worn o-rings on the pump cause the shift delay. The hard shifting could have been from a blockage or sticky valve that has worked its way loose. Perhaps the blockage has now deposited itself elsewhere.

[corict75]

I started having a problem with my 09 Impreza automatic when it was just under 60K miles (aka under warranty), nearly 3 years ago. While driving it would slam and feel like it had been shifted into Park for a split second, sometimes one big slam, sometimes several shudders. Some but not all the time 3 lights would come on- AT oil temp and 2 icons to do with AWD (can't be exact, don't have the car now). Repeated trips to the dealer never yielded a read of ANY codes. Things seemed to get better when I had a routine change of transmission fluid.

 

Fast-forward to August of this year, the problem happened yet again. This time they got a code read and replaced the valve body, a $1300 job OF COURSE not covered by the warranty, even though the problem is well-documented as ongoing from when it was covered.

When I picked up the car I was told this is a "highly unusual" problem caused by metal fragments in the fluid, but there might be further repairs needed which would only be known after I'd driven it more.

Three weeks later, same problem. NOW they say it's a short in the transmission harness wiring and the transmission is not faulty at all, while still stating that the valve body did  need replacing last time. So, TWO separate problems both causing the exact same symptom? Really? And today I was told that the metal in the fluid is normal. So why did the valve body need replacing, then?

 

Meanwhile my August case with national Customer Service has somehow been closed for the valve body issue and they take no responsibility. As of yesterday, however, I had been told it was still being investigated. They are willing to cover the harness replacement but given the conflicting info I now don't trust anything I'm told. HELP!

[1 Lucky Texan]

is the transmission pan dented? Any evidence of rodents chewing on cables?

 

anyway, you could start a new thread asking for a shop recommendation near haverhill, someone may be able to direct you to a good Subaru mechanic.

[corict75]

1 Lucky Texan- I don't know about the pan or cables, but you can be sure I will ask. The service rep was not able to go into much detail about things and promised to have the mechanic explain how this is all one problem. I am also going to ask what the codes were to get other opinions. Thought I was doing best for the car to go where I bought it "Certified Pre-Owned". They are usually very responsive and helpful. It's more the national level of Customer Service that leaves a lot to be desired.