driveability problem with '06 Baja Turbo; need your thoughts

[Dave G]

I have a 2006 Baja Turbo with auto transmission. Approx 51,000 miles.

While driving the car, the engine seems to be losing power and revs on-and-off, about every second or half-second, as if I was fluttering the gas pedal. I'm steady on the gas pedal, but the car acts like the fuel is being cut off or reduced every half-second or so. So it feels like surging on and off.
Its noticeable at light throttle, and at full throttle, but its worst when I'm anywhere in mid-throttle.
There is no Check-Engine-Light (CEL).

The car drives, and would get up to 90+ on the hwy when I tried full-throttle, but its certainly not getting up to speed anywhere near as quickly as before.

Last year I had a CEL along with the engine not revving or not being able to go faster than 40mph, which ended up being something having to do with intake butterfly valves (?) being stuck closed on both sides. It sounded odd that both sides would go bad at exactly the same time. The dealer said they'd have to replace them at $1,300. I posted on here, and you folks said that it was probably the electrical connections to those items. The problem went away the next day, so no repair was ever done. Now, a year later, this different problem has arisen, with no CEL, but I suspect this problem might be related. Last year, the electrical problem caused the intake butterfly(?) valves to stay closed. This time, I'm wondering if those valves are stuck in some partially open position.
Or is the source of the problem something completely different?
Could it be a fuel filter problem?
How about the fuel pump?

I can take the car to the local Subaru dealer, but I'd like to hear from all of you first.

Thanks in advance for any responses.

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[Benhart21]

Honestly, instead of listening to us making guesses, I'd just take it in and get it fixed while it's still under warranty.

[Dave G]

How do you know the fix will be under warranty?
The car has 51K miles on it, so the bumper-to-bumper warranty is long gone. The powertrain warranty (5yrs/60K miles) is still good, but how do you know its going to be something covered under the powertrain warranty?

When I had the problem last year with those intake butterfly valves, the dealer told me that the fix for those was not part of the powertrain warranty.

I'd like to be prepared with info when I go to the dealer, since I have not had very good luck with the Subaru dealer service depts around here.

I'm really interested to hear from anybody else who has seen this problem, and what the fix was. Or some educated guesstimates on what the problem might be, from some of the guru's here.

[JLBaja]

Don't know where you're planning an taking it for service, but you may want to try Becker in Allentown, PA.

[Dave G]

I'm in Chester County, so Allentown is a bit of a hike for me. In fact I'm concerned about whether the car would make it that far.

I looked up the info from last year. It was listed as Tumble Generator Valves (TGV). This site talks about removing them or removing the butterflies, etc: http://subaru-offroad.blogspot.com/2...gv-delete.html

Does anybody here think the Tumble Generator Valves would cause the problem I described above?

Any other ideas on what could cause the symptoms/issues I described above?

[moonzie]

Originally Posted by Dave G

but how do you know its going to be something covered under the powertrain warranty?

When I had the problem last year with those intake butterfly valves, the dealer told me that the fix for those was not part of the powertrain warranty.

THAT doesn't make any sense to me.

Powertrain warranty - from what I understand it to be - is that anything that has to do with the engine powering the vehicle to the transmission gearing the power to the drive shafts and axles driving the wheels. In a sense, it is the core components of your Subaru.

If there are tumbler valves or intake valves that are getting stuck - those components should be covered by the powertrain warranty of 60k/5 years! Is there any other dealership in your area? If not, ask them why it is that problems related to your engine are not covered under the powertrain warranty - that's absurd!

[moonzie]

And a steady symptom of hesitations could be caused by LOTS of things. O2 sensors, bad plugs, loose wire, fuel delivery issues - it could be anything man.

Take it to the dealer and talk to em. You're experiencing powertrain issues. Your car is covered by a powertrain warranty. Simple as that.

[pagris]

Originally Posted by moonzie

Take it to the dealer and talk to em. You're experiencing powertrain issues. Your car is covered by a powertrain warranty. Simple as that.

Moonzie is absolutely right - take it to the dealer - if they give you a hassle about it, go to another dealer or call SOA. You have a powertrain issue, no question about it.

[Dave G]

Originally Posted by pagris

Moonzie is absolutely right - take it to the dealer - if they give you a hassle about it, go to another dealer or call SOA. You have a powertrain issue, no question about it.

I appreciate the input and the comments.

I took the car to the dealer. They got a CEL, so they were able to diagnose the problem. They say its a bad O2 sensor. Its not covered under the powertrain warranty, so I'll have to eat this one. They don't have the part yet, but after they get it and do the fix, I'll post again with info on whether the fix worked or not.

[J.Leonard]

Jeez what is it with the O2 sensors? It seems like every other trhead I read about someone having trouble has something about an O2 sensor in it.

[bulwnkl]

O2 would be nice if that's it, though that's awfully soon for an O2 sensor to go. Also, there is an emissions warranty on EVERY new vehicle sold, and it's required to be there according to federal law. I do NOT recall the details of what's what, so review your warranty book, but my first thought is that this, as an emissions control performance issue, may be covered by that warranty. Again, check your warranty book to verify.

My own personal guess is that this is still an electrical issue, and maybe or maybe not a hard-part failure as well. Interested to hear how it turns out.

[Dave G]

Originally Posted by bulwnkl

O2 would be nice if that's it, though that's awfully soon for an O2 sensor to go. Also, there is an emissions warranty on EVERY new vehicle sold, and it's required to be there according to federal law. I do NOT recall the details of what's what, so review your warranty book, but my first thought is that this, as an emissions control performance issue, may be covered by that warranty. Again, check your warranty book to verify.

My own personal guess is that this is still an electrical issue, and maybe or maybe not a hard-part failure as well. Interested to hear how it turns out.

I don't have access to my warranty booklet/info, because its in the car which is at the dealer, but I did look at this webpage from the EPA, which explains what automakers must cover and the length of warranty etc, for emissions related parts:
http://www.epa.gov/obd/warranties.htm
The oxygen sensor is listed as an item that must be covered for at least 24-months/24,000 miles. It doesn't seem to be part of the required longer emissions warranty.

I'll certainly post again after I get the car back, and we see if the O2 sensor repair did the trick.

[JLBaja]

Did you take it to Rafferty?

[moonzie]

O2 sensor, hmm. See - I would have thought that any failure of the exhaust would be considered part of the drivetrain.

For an O2 sensor to fail at 51k miles, that makes me frown. My `04 Turbo with 137k miles is still on all original O2 sensors.

EDIT: AND - that would make sense if it was surging/hesitating with no CEL - but now as the sensor gets progressively worse it will eventually throw a CEL. I'm sure it was confusing the hell out of the computer!

[Dave G]

I got the car back yesterday. And the O2 sensor replacement seems to have worked.
For anybody interested, the part number listed on the dealer service invoice is: 22641AA260
The total cost of the repair was a bit over $300.

Upon driving the car away from the dealer, the driveability problem was definitely fixed, but I noticed right away that the car seemed to feel like it was down on power. It felt more like driving a non-turbo version.
I recalled seeing some internet discussion about needing to do an ECU reset after such a fix.
see #10 (by ChosenWon): http://forums.nasioc.com/forums/showthread.php?t=41511
and see http://www.clubwrx.net/forums/mainte...ecu-reset.html

So, I disconnected my battery, waited a while, and then reconnected it, reset my clock and radio stations, and did a spirited drive, as recommended in those discussions.
I was doubtful that this "ECU reset" procedure would do anything, but to my surprise, it made a difference. Not a gigantic difference, but certainly a noticeable difference, especially in how much smoother the engine operated. It was noticeably smoother at idle, and it felt more powerful throughout the rev range while driving. My wife was with me, and she confirmed that I was not imagining the difference.

I give thumbs up to the dealer (Roberts Subaru, in Downingtown) that did the work on this. They diagnosed the situation, got the part shipped in, and got it fixed as promised. I'm happy.

As an aside, I noticed that another Baja owner had reported essentially the same driveability problem which also ended-up being an O2 sensor problem. See #2 by nasioc member toolbox1234 here: http://forums.nasioc.com/forums/show...=oxygen+sensor

[moonzie]

Glad to hear it's fixed and you're satisfied.

If it were me tho, I still think a component failure of the exhaust system is still considered part of the drivetrain. $300 out of my pocket is nearly enough for a whole new set of tires or an AT fluid change.

[Dave G]

Originally Posted by moonzie

I still think a component failure of the exhaust system is still considered part of the drivetrain.

I agree, but unfortunately its only covered under the 3/36 warranty, and I was outside of that. And I did not purchase an extended warranty.
I suspect they think of the O2 sensors as maitenance parts, similar to spark plugs.

Originally Posted by moonzie

$300 out of my pocket is nearly enough for a whole new set of tires or an AT fluid change.

Yep. Cars can be money pits, but its not bad enough for me to want to get rid of the car. At least not yet.
I looked up independant prices on O2 sensors when awaiting completion of the car. At the time I didn't have a part number, etc, so I just searched under Baja Turbo, and many places were charging $200 or more for the O2 sensor part, so the $199 part price through the dealer service dept seems in line. The remaining cost was the diagnostic and labor/install charge.

Hopefully no more big expenses until I get to 100K miles...

[shipjumper]

is there a way to check on an o2 sensor without the dealeship? can ROMRAIDER logging see issues with it?

snap-on scanner?

oh, and was it the front or rear o2 sensor?

BTW o2 sensors SHOULD be part of the 8yr/80,000 federal emmisions warantee

[Dave G]

Originally Posted by shipjumper

...was it the front or rear o2 sensor?

The dealer (and it's invoice) never mentioned anything about front or rear. Can you determine which it was by the Subaru part number?: 22641AA260

Originally Posted by shipjumper

o2 sensors SHOULD be part of the 8yr/80,000 federal emmisions warantee

I think we all agree that it "should"; but its not.
As mentioned above, take a look at this webpage from the EPA, which explains lengths of required warranties by auto makers for emissions related parts:
http://www.epa.gov/obd/warranties.htm
The oxygen sensor is listed as an item that must be covered for at least 24-months/24,000 miles. It doesn't seem to be part of the required longer emissions warranty.

[Cooter13]

Originally Posted by Dave G

The oxygen sensor is listed as an item that must be covered for at least 24-months/24,000 miles. It doesn't seem to be part of the required longer emissions warranty.

Could it be that manufacturers know that this part is prone to failure within a short period of time, compared to other components of the emissions? Does anyone know why the O2 sensor fails? Is it the gas, poor air filter, climate, or just because it is an expensive part that is hard to replace, aka who the halibut knows.

[moonzie]

Originally Posted by Cooter13

Could it be that manufacturers know that this part is prone to failure within a short period of time, compared to other components of the emissions?

As I stated previously, I'm on 138k miles now on factory original O2 sensors - no fault yet.

Originally Posted by Cooter13

Does anyone know why the O2 sensor fails? Is it the gas, poor air filter, climate, or just because it is an expensive part that is hard to replace, aka who the halibut knows.

Yes to all mentioned above. Some sensors, depending on their operating environments, will be prone to pre-mature failure.

In my opinion, unless you're engine is running way out of spec (burning oil, burning rich, burning coolant) your O2 sensor should last AT LEAST 60k miles.

[skidanski]

Originally Posted by Benhart21

Honestly, instead of listening to us making guesses, I'd just take it in and get it fixed while it's still under warranty.

^^sage advice

[shipjumper]

I personally am having random surging / hesitations that I cannot track down... no CELs either...

[Dave G]

Originally Posted by shipjumper

I personally am having random surging / hesitations that I cannot track down... no CELs either...

shipjumper,
I had the surging/hesitations for two days without any CEL's. After taking it to the dealer, they drove the car, and during one of their drives, the CEL came on. The dealer service mgr told me that if they had not gotten a CEL, that it would've been difficult to diagnose, and he wasn't sure how long it would've taken to properly diagnose.
So its possible that you have an O2 sensor problem, and it might be prudent to have that checked first. Apparently there is an easy way to test O2 sensors, so the dealer should be able to do it quickly. But as another person in this thread has pointed out, its possible that there is another problem that led to an O2 sensor failure.
For my car, it appears that the O2 sensor replacement did the trick, because the car runs great now, and feels stronger than it did, plus there is now a slight increase in gas mileage. For now, it appears that there are no other driveability problems with my car, so I have to conclude that the O2 sensor was indeed the problem.
Dave G

[shipjumper]

yeah. my mileage is sucking..

maybe the o2 is the way to look...