In 2014, I again posted to subaruforester.org concerning maintenance issues with the Forester. Here’s my local repost.

Summary: intermittent failure to charge battery accompanied by in-use electrical intermittency resolved by alternator replacement

After getting the seals done at AWD, I mostly took the car to the much closer Suburb Service in Shoreline and they have done some minor parts work, such as a headlamp and most recently a front axle. No issues with the quality and pricing of their work but their shop prefers an early-morning check-in and drop-off which just doesn’t work with my schedule.

Over the past year or so the car has exhibited occasional electrical issues, observable primarily when the car fails to start in the morning after being driven, with no apparent weather dependency at first. I replaced the battery about a year ago in an attempt to address this issue, which seemed to work for a while.

Then, as this summer (2014) has brought months of record setting traffic problems to the Seattle area, on several occasions I have found myself in stop-and-go traffic for several hours. On the first of the occasions, the day that a fatality accident closed Aurora southbound, I noticed some dash lights flickering when the car was idling. the flickering seemed to coincide with the engine running slightly rough on idle. the flickering also affected the a/c and the radio, which emitted static as the flickering was observed. given that traffic was not moving I thought, ‘huh,’ and without thinking about what i was doing, turned the car off.

Bad move, as the car would not restart. the starter turned over a couple of times but after that was flat. I was able to push the car into a parking spot which was right next to the place the car died, thankfully, and settled down to wait for the engine to cool down.

After about 30 minutes, I could touch the engine block with my finger and tried to restart the car. nothing. Then I realized i had a jump box with me and tried that. The car started immediately. I realized i was in the window at the end of the day to leave the car parked until my event was over, paid for parking, and came back to the car several hours later. the car needed the jump box again, but started fine and ran well all the way home. the next day it did not need a jump.

Over the next few warm days I drove it I experimented with the electrical load and determined that the a/c was most likely to produce the dash flicker and drained battery. I never took careful note of which dash lights were flickering except for the ‘A.T. OIL TEMP’ light.

I had a different ship than the one that suggested the battery replacement examine the car’s electrical performance and harness and as the first shop has found they reported the car as sound.

Finally, I made an appointment to get the car examined after I had determined that the a/c would drive reproducibility in the issue at Greenwood’s Scanwest, a mixed SSAB / Subaru shop.

They immediately diagnosed it as the alternator and performed the replacement with a rebuild, which has resolved the issue.

I’m happy with the resolution here and feel that Scanwest did great. They also replaced the shifter bulb for parts only, no labor; performed the diagnosis for free; and did this as a walkin overnight. so, great job.

The only thing I’m still puzzling over is this: ever since we bought the car at 70k, the transmission has always been hesitant to engage. As the car aged, it became even slower to engage, and developed a notable, distinct ‘CLUNK’ as the gearing set.

Now with the new alternator, the transmission’s hesitation HAS VANISHED. No hesitation. No ‘CLUNK’. The transmission operates as, I guess, automatic transmissions are supposed to operate, although as this is my first non-stick, I actually don’t know what to expect.

So here’s my question: how can changing the alternator have affected the performance of a mechanical part like that? Does the alternator play a documented part in the transmission? If so, why on earth didn’t a single experienced Subaru mechanic notice that issue and observe that the alternator might be the issue?

If it’s not the case that the alternator has a known role in transmission performance, should I ask the shop if they went above and beyond and turned a bolt or something in the transmission along the way? It’s definitely not on the statement I have in hand. Anyway, I’m definitely not complaining, just pleased and mystified.

There were no responses to the post. I no longer notice any difference in the transmission shifting behavior. The transmission is notable slow in going into reverse. I assume this is a symptom of wear in the transmission.