2000 Leg. OB engine problems, need help please

[JodyR]

A little background, this is my first Subaru, I've had it for 3 months. I traded my top heavy Blazer in for better handling and MPG. It's a 2000 Legacy Outback, 129K, 20-22mpg - I was hoping for better MPG and power and wanted the manual, but found a very clean auto tranny, loaded out for 8 grand:brow: .

 

I don't hot rod, mostly hwy miles. CEL came on next day after buying so I replaced the knock sensor, no biggie, no more cel's. I has new tranny fluid, fuel filter, plugs, valve cover gaskets, spark plug oil seals, and belts. I also confirmed that it has a new timing belt.

 

On to the problems.

 

1st issue, CEL came back on a few weeks ago, went to advance, said it was oxy sensor, didn't know which one, so I took it to the local general auto mechanic (good guy, but doesn't know subies) and he hooked it up to his big snap-on computer and said it needed the front cat. OK, so I started saving up for the big oem purchase cause I heard aftermarket cat converters don't flow correctly and they will cause cels. Any truth to that:confused:

 

It started running progressively worse in the next 2 weeks. First it just started stumbling right off idle when it was cold. A few days latter it started falling on it's face from idle all the way up to 2K rpm, stumbling and spitting back like the timing is off. No power until 3K where it smooths out. I figure, man this cat is really getting clogged, I better fix it soon, so I sold my RM250 to pay for the thing, take it back to the mechanic for the new cat. He says there are new codes, misfire and whatnot, finds the plug is submerged in oil and replaces the Valve cover and spark plug seals, plugs, fuel filter and adds a bottle of Lucas fuel injector cleaner. So for 400$ I'm out the door and it's running ok. I drive half a tank out of it and it's doing it again. same stumbling/spitting back until higher RPM's. I pull the plug wires and no oil in there. I have a suspicion that the plug wires or ignition coils are the problem. It's back at the mechanic right now.

 

What do you guys think I should do? I'm decent with a wrench and could have easily done the things that he did if I had known what it was. I took it in for a cat, remember?

 

:banghead: :banghead:

[JodyR]

I forgot to mention that the mechanic said that the rich O2 sensor reading might have been from the plugs getting shorted out in the engine oil, and to wait and see if the plugs cured the problem. I agreed.

[friendly_jacek]

F***ing stupid mechanics!

Replace the front O2 sensor.

Read also this recent thread:

http://www.ultimatesubaru.org/forum/showthread.php?t=55507

 

I also have 2000 with low miles and replaced the sensor twice, first time at 20000 when it was recalled and second at 50000 miles because MPG sucked. Never got a code. Some people get codes for cat, misfires, etc.

These are wideband sensors with working temp 700C, twice the regular sensor, and failing often. Did you do the 2001 recall?

[JodyR]

Thanks for the link on that thread, friendly. I must have read 50 threads before posting, don't know how I missed that one. I will call my local dealer and check for the recall. I'm not sure when or if it was done, only had it for a couple months.

 

Yesterday, the mechanic said that the #2 cylinder plug's isolator was cracked (only 1/2 tank of gas on new set of Denso plugs) and he is at a loss for a reason. I am thinking it was just a bad plug or he may have cracked it during install (it happens). He replaced it and It seemed OK, so I put 50 miles on it last night, and it runs pretty good, I would even say it ran pretty d**n good if you keep the RPM's above 3K. My uncle talked me into doing a comprehensive carbon removal procedure last night (wide open, emply interstate). I was pleased to know that my little ol' mild looking OBW is capable of doing every bit of the 120MPH on the speedo and then some. Uncle said I had been driving it like a grandma and I need to "blow it out" a little. I agreed.

 

Sorry, rambling, back to the plugs. He installed denso plugs. Are they OK? I went to Advance auto and procured some NGK V-powers. (They were the same price as regular NGK, only difference was the electrode has a small v notch in it's tip) I haven't installed them yet, waiting to see if you guys approve the purchase.

 

I really think that the O2 sensor is my problem. We are talking about the one in the front cat, after the header pipes merge, right?

 

Thanks again for the help.

[idosubaru]

use NGK plugs and most importantly use Subaru OEM wires only. i use magnecor myself, but would not trust any aftermarket wires otherwise. these engines are not forgiving when it comes to ignition. you should get a cylinder misfire code though if your ignition wires/plugs are to blame, but not necessarily true all the time.

[JodyR]

Thanks Gary, I always trusted NGK in the past. Are V-POWER's OK?

 

The car has good looking OEM wires, which I will check tonight, per forum recommendations.

 

I'm getting ready to run down to my car and get the vin# to call the dealer.

[JodyR]

I talked to the 'roo service manager, he said there are 2 recalls out on mine and both have been done. O2 A/F sensor and the Engine coolant additive.

 

He recommended Standard NGK plugs, I'm going to swap the NGK "v-power's" unless otherwise advised.

 

They have an 02 sensor in stock for 80$, does that sound about right, or should I search elsewhere?

[friendly_jacek]

I talked to the 'roo service manager, he said there are 2 recalls out on mine and both have been done. O2 A/F sensor and the Engine coolant additive.

 

He recommended Standard NGK plugs, I'm going to swap the NGK "v-power's" unless otherwise advised.

 

They have an 02 sensor in stock for 80$, does that sound about right, or should I search elsewhere?

 

This is a very good price, you can only get it cheaper from online subary dealers ($60+S&H). Remeber, this is A/F ratio sensor, and not just generic O2 sensor, few aftermarket options.