Check all the grounds - battery and engine to body - to make sure they’re all in good shape without corrosion, and then also check to see if there are any air leaks (e.g., a leaky vacuum hose).

 

A good place to start would be the PCV hose. It’s on top of the engine, plugged into the throttle body on the passenger side. They tend to crack first.

 

AF sensors go to crap about 100k miles in.

Find an indie and kiss the dealer goodbye.

 

AF sensors go to crap about 100k miles in.

Find an indie and kiss the dealer goodbye.

As in air/fuel?

 

You're getting a light show on the dash to get your attention - something is amiss. Most modern vehicles illuminate the ABS light and disable cruise control when there's an active fault (often the check engine light will also be illuminated). This is, again, to get your attention. The OBD system needs to be scanned for codes - post them and you might get more help. But, if you're not much of a back yard mechanic, then, as suggested, just seek out a reputable independent mechanic and stop wasting money with the dealer. Subarus don't generally require any special skills to work on.

 

Most auto parts stores will read the code for free. NAPA won't but Advance and Auto Zone will.

As said above, don't take this old car to the stealership for service. Where I live, it is easy to find a local repair shop that knows these cars. There's even used car dealers that seem to favor these cars.

 

2.5L? I had that and it only showed up in -0F, turned out to be faulty intake gasket on my 14 2.5i

 

Thanks all. The P0171 is the only code it showed. We had only taken it to the dealer because it was intermittent and showed both ABS and Airbag lights; they weee not worried about it at all. But it seems strange that a mixture sensor error would disable ABS and cruise control. I know ABS was disabled because I tested it in an empty parking lot; didn’t test the airbags .

 

MIL will disable VSA, traction control and Cruise and any other safety system outside of ABS. MIL does not disable ABS. unless the ABS module reports a fault, it remains active.

 

My 2006 Impreza would disable cruise control, along with the cluster light show, when the CEL was illuminated. My buddy's 10 year old Honda recently did the same thing. It may seem strange, but there are valid reasons for this behavior, and AFAIK it's been fairly common for decades.

 

What are the air bag fault codes? The air bag system is never disabled unless there's a problem with the air bag system. So something is going on and now I'm thinking electrical.

 

There were no airbag fault codes but the light on the dash was flashing. It’s cleared now so I can’t post a picture.

 

That's not right. If that light flashes or came on solid there would be fault codes stored. May be shown as "history", but it'll be there.

 

I had a similar issue on a road trip last month. Threw a CEL and that disabled cruise and x mode was flashing. Pulled over and disconnected negative terminal on battery for a few minutes. The CEL never came back on after 400 miles back home. When I got home I checked for codes and got the P0174 and P0171. Cleared those and they haven't come back on in a week of driving. Still concerned.

 

If you search the forum for those 2 codes it looks like an intake leak is a common culprit. You can always try to spray some carb cleaner around the engine while running. Another example, someone had their air filter messed with and then re-installed backwards - had to replace it and clean the MAF, then all was well.