a couple of questions.....

[subymtnguy]

After reading this board for about the past year....I have a couple of questions concerning my 92 Pearlie...

1) I understand Subaru installed a external tranny filter on the early SVX's; (92 & 93 models...). Was this after they discovered they were facing early transmission failures?? Where do I look for this filter? I don't know if it was ever done to my car or not....
Was this a recall item?
NOTE: I am still on the original tranny!!

2) I have read many post about dis-connecting the battery over night, so that the ECU will re-set itself according to my driving style. I bought the car from a woman, who I know did not drive the way I do. Would I gain anything by doing this?

The car has 160k miles, and is in excellent condition....

Thanks gang for your help and suggestions....

[ensteele]

I think it was a recall on 92 and 93 - someone else can give more information on that and why. The filter is installed below the battery and bottom of the radiatior. It is a canistor a little bigger than your fist. It usually has a quick release that holds the filter for being able to change it easily. When I got my 93, it did not have it, but my 92 did. I have Perma Cool filters on my cars now, because I like the canister type better, and they are eaiser to change. I also have a temperature gauge installed on the filters.
As far as the ECU, you probably would not have to disconnect the battery because the ECU is always adjusting to your driving habits. After being driven differently, it would adjust to your driving style. I don't think it would do much at this point, unless you had problems with gas or some other problem. I am sure someone else will comment if there is more to it than that.

Good Luck

[Beav]

Tom,

I have tried several times to explain away the 'learning computer' fallacy. The computer absolutely does not learn any of the driver's traits. What it does do is relearn different sensor values as they system ages and resistance increases. It works like this: if the TPS should be 1.3volts when the crank sensor reports 1300rpm, the engine temp is 184°, the MAF is at 1.67v, etc., etc., etc., and it's now showing 1.42v consitently instead, it will update/relearn this new value. (the numbers and sensors are just grabbed from thin air for the sake of explanation) It does not think to itself, "Gee, Tom's riding me hard today, I'll give him some extra power." I don't know who dreamt this up, but they were totally off the base.

Yes, disconnecting the battery overnight will erase the stored values and force the ECU to start from scratch and relearn the values again, a process that can take several days to complete. Please realize that the ECU doesn't make drastic, snap changes. It 'watches' what happens over a series of 'drive cycles' to ensure it doesn't try to make adjustments for a 'fluke' situation. Plus some parameters will have to wait to be sorted out until after the more important values are reset. And all during this process the car may run off kilter, just as a partially adjusted carbureted engine would. BTW, a drive cycle is starting the engine from dead cold, warm up and driving at low and hi speeds, shut down and cool off. You can't start the car up and drive around the block (well maybe you can considering the length of your blocks ) and call it a drive cycle. If the car doesn't spend enough time at speed, it won't be considered a cycle and nothing will be adjusted. That's why I said it could take days to complete a relearning sequence. It took mine three days just to relearn the idle speed after cleaning the throttle body.