[RichDesmond]

Got stranded today by our '10 Outback with the following symptoms:

Got on the freeway and noticed that if I coasted and then got back into the gas gently the engine would surge, with a frequency of about a couple of times a second. The first few times it was bad enough that the tach would jump up and down. Next few miles it would still do it, but not as much. Got off the freeway and the engine died as I was coming to a stop. Fired right back up, but running rough. Had a hard time keeping it going, surging and wanting to die. Had to shift into neutral as I came up to a stop and rev the motor to keep it going. Finally parked it and called a friend to come get us.

Searched and couldn't find anything similar, anyone have any ideas as to what's wrong?

TIA

 

[1 Lucky Texan]

IACV, TPS and failing front O2 sensors can cause surging.

is the CEL on?

if so, get the codes and post them.

history on the car, miles, wrecks, mods, repairs, maintenance done - especially recently.

did you purchase gas just before this occured?

 

[RichDesmond]

IACV, TPS and failing front O2 sensors can cause surging.

is the CEL on?

if so, get the codes and post them.

history on the car, miles, wrecks, mods, repairs, maintenance done - especially recently.

did you purchase gas just before this occured?

It has 59k miles, no wrecks or mods, just scheduled maintenance. CEL isn't on. About 200 miles since fill up, so I don't think it's bad gas.

 

[1 Lucky Texan]

odd - I'd probably try to scan for any stored or pending codes. Check engine oil and other fluids too.

recent maintenance work? (just wondering if a hose or connector is loose)


sounds like an auto transmission so - shifting into neutral you said you had to manipulate the throttle to keep in running, doesn't seem like a TC or other tranny issue,,,,

I dunno much about the newer cars - it may not have a TPS.

pulling plugs after running a little bit might show one wet with fuel from a bad injector - but I'd wonder why you didn't at least get a misfire code thrown.

weird

 

[RichDesmond]

Well, mystery solved. Had it towed to the dealer and they said the air filter (which we'd had put in at a quickie oil change place) didn't fit right and had let some debris in, messing up the air flow sensor. They pulled that out and cleaned it, all is well.

Thanks for the input.

 

[1 Lucky Texan]

kinda surprised you didn't hear a 'whooshing' noise. If the filter box is similar to older cars - there are plastic tabs that can easily be misaligned when installing the air filter.

glad it wasn't serious.