Idle Pulsing and Car Won't Make Power When Cold

[JL421]

I'm going to pull the spark plugs today.

[JL421]

New v. old plug comparison @ 200 miles.

Top of plugs:



Bottom of plug 1:



Bottom of plug 3:

[JL421]

I keep finding random bits of info that might pertain to the issues I'm having...

So far, front driver side axel replaced about 10k miles ago due to a torn cv boot. Axel was aftermarket, so possible issues?

I keep coming back to valve guides, which would suck.

Front O2 sensor.

Bad ECU.

Bad knock sensor.

Bad valves.

[cardoc]

Its running too rich.

Thermostat good? Good fuel?

Since you can't record data, I will take a stab and say replace the front O2 sensor. Its primary in controlling fuel trims.

[JL421]

Fuel is good, running 87 octane without ethanol. Also ran a tank of 91 w/o ethanol and a can of seafoam in the tank.

I believe both O2 sensors are original, thermostat is definitely original.

I've been wondering about the thermostat every once in a while. I had a summer when the radiator fans wouldn't kick on, but the temp gauge never went over half way up (180-196 F) if I remember. Cleaned the contacts on the fans and everything was just fine.

The other day the wife said the temp gauge went almost completely up to the red, but as soon as she started moving it cooled down to normal again. Checked the fans and they would kick on for me when I turn the A/C on so they should be good.

I've looked and changing out the thermostat doesn't seem like anything too major, so I'll replace that while I'm down there.

Looks like it's either OEM or Bosch for a new O2 sensor, which Bosch should be just fine.

I'll grab a new OEM thermostat and gasket and let you know after I get it in.

[JL421]

Well...I learned something today...

My car is actually California Spec...or at least the O2 sensors are. Ya...

So I wait until Wednesday to replace the O2 sensor.

[WiserLEONIDAS]

Hi, new user and owner here but I am having major issues with my 98 Outback 2.5L. One of the major issues is the fuel injectors are leaking around the o-rings. I bought a generic o-ring set and it seemed to fix the idle problem. Very tough getting the FIs back in though...be warned! Good luck and will be posting much more often with questions. Let me know if this helps?

[JL421]

I pulled out my scanner to look through the old data, and I found some old freeze frame data from about a week after the problems started developing.

Fuel Sys 1 : Closed Loop
Calc Load (%) : 15.3
ECT (C) : 96
SFT B1 (%) : -0.8
LTFT B1 (%) : -7.0
MAP (kPa) : 58
Eng RPM : 1,493
Veh Speed (km/h) : 60

[cardoc]

Yep. Rich. The LTFT -7 means the ECM is pulling fuel.

And Wiser, the injectors would have gone in easy with the OE seals and a little oil. Beck Arnley.

[JL421]

Well replaced the O2 sensor...

I didn't reset the ECU yet, but the LTFT is now almost always 0...

The STFT is now bouncing around like a maniac...

I took it for a drive and it was still doing it's thing where it won't go until it's warm, and now I can actually watch things.

When it is not moving, the STFT is between -25 and -20 when opening the throttle, let go it's between 13 and 25. The timing advancement is also at -1.5 degrees when throttle is applied, then relaxes to 5 when there is no throttle. Also strange is that the fuel system is immediately in closed loop mode.

When it finally starts moving, the STFT acts more as expected between 15 and 20 when applying throttle, but at -20 when no throttle. Timing advancement is always between 5 and 15 degrees now.

Intake vacuum is at 47 kPa when idling cold and warm. Didn't look when I was applying throttle.