My 2010 Subaru Outback recently surprised the hell out of me by simultaneously turning on the brake warning light, the traction control light, the check engine light and (just for a bonus!) disabled my cruise control while flashing the cruise control light. I pulled over, quickly surmising that all of those systems could not have failed at 70 MPH without instantaneous death to either me or the vehicle. Both apparently still being alive, I tried turning the car on an off to reset the lights. No go. Subaru was not going to miss this chance to get me to the dealership! (who I had avoided to this point!) As I was far away from home and the car being very healthy, it seemed, I decided to drive on. I proceeded to put a couple of hundred more miles on the car before I got back to town.
On to the dealer, who informed me it would cost me $120.00 to determine the cause of my problem. My car had 39,000 miles on it, 3,000 miles beyond the warranty end. How appropriate!! So I paid and learned that I have an error code of P0171, “Fuel Trim Malfunction (Air/Fuel too lean)”. They would gladly order the part and install it for another $375.00. This is a sensor I can buy online for $131.00…so OK I’m being screwed a bit, but hey they did throw in a car wash for my $120.00.
So I guess I’m wondering about a few things…why would this sensor set off every light on my dashboard and disable my cruise control? Seems a bit overblown for running a bit lean. My gut tells me Subaru has a sensor/software problem they are not owning up to. I’m a big fan of conspiracy theories and this really smells like one…
Second, jeez, I’m only 3K miles over warranty, don’t you think they’d cut me some slack. I mean I love my Subaru, or did anyway, until this happened. Now it’s just another POS car that breaks for no apparent reason.
I will probably go back and have them change out the sensor and beg for mercy on the charges. Has anyone else had this experience with their Outback??
When the CEL lights up, the underlying problems that caused it to glow will also cause systems that rely on proper operation of the engine to shut down.
So, that fuel trim problem caused the CEL to light up, and then it led to disabling of the cruise control, the traction control, and most likely also the Vehicle Dynamic Control. That is standard fare on any modern car with all of these electronic systems. As to why the brake system warning light also came on, I cannot say for sure, but it is also likely to be the result of the CEL lighting up.
Since the car is only 3k past warranty expiration, it is possible that Subaru of America will give you some assistance with the cost of this repair. Call the toll-free phone number listed in your Owner’s Manual, and politely state your case.
A hot-headed attitude will not be likely to yield any results. I suggest that you call on Tuesday, after 10:00 AM, so that the person fielding your call will have already had their morning coffee. If you approach this person in a rational, polite manner, they just might give you some assistance with the repair costs.
On a vehicle this new, a P0171 code would most likely come from a vacuum leak, not a sensor. Although for $120, you are supposed to get one hour of troubleshooting time, not just a reading of the codes.
The dealer should have performed an independent test of the sensor before giving you this diagnosis. I would ask them if they did that and if they checked all the vacuum lines. If you find a disconnected or split vacuum line, I’d say the dealer owes you a partial refund.
I agree with Keith. The CEL error code isn’t turning on because the sensor is bad, it is because there is a airleak on the bank 1 side somewhere and the sensor is detecting that. If the shop stated that replacing the sensor is going to fix that problem I would be a little concerned. If Subaru won’t cover this repair under warranty you may want to find another shop to work on it, though they are ‘supposed’ to be the experts on the car.
As for the other warning lights issue I suspect that there may be a problem with the alternator that is causing that issue. Excessive AC ripple may be the cause there. Have the alternator checked out to make sure it is working as it should be and especially for check the AC ripple voltage. There should be less than .1 volt of AC voltage across the battery while the engine is running around 2,000 RPM. It may help to fix this problem first to see if there may be a possibility that it is causing the error code problem also.
I’m in agreement that the problem may not be this mysterious sensor you speak of (assuming it’s the proverbial O2) but I think you’re way off base in your reasoning.
There is no conspriacy going on.
You’re only 3k miles out of warranty and think that you should be an exception to the warranty rule. Well, everyone on the planet wants that exception rule be it 3k, 33k, or a 100k miles out of warranty. If Subaru covered everyone that felt slighted there would be no Subaru problem because Subaru would be bankrupt and gone.
You’re comparing a part you can buy on-line for 131 dollars to a 375 dollar price tag for both the part and labor for a factory OEM and consider this to be shady?
They did not screw you out of a 120 dollars either. You were told in advance the cost of any diagnosis and you approved the same.
Maybe you think the mechanics should work for free? I guarantee you that a mechanic can spend 50 hours a week scanning and diagnosing cars for free if it were left up to the customers.
So now you’re upset with me. So be it.
Your car is out of warranty, sorry. But whether it’s 3,000 miles or 30,000, it’s over.
There’s no conspiracy going on here. Auto electronics are now an integrated multiplexed system on the car. The cruise is not separate from the ABS, traction system, or engine control. A fault in one system can cause trouble with the others. When a fault is detected in one system, others may be disabled as a precaution. This strategy is normal and not unique to Subaru.
There’s no way to determine just by the trouble code whether your fault is with the sensor, a fuel injector, or a vacuum leak. That should have been determined (and the diagnosis guaranteed) as part of your $120 diag process.
There are other codes used to indicate a problem with the operation of the sensor in question. To me, the shop makes a big mistake in saying replacing the sensor will fix this problem. If that is what was really stated anyways.
$120 is pretty steep. My local dealer in NH charges $40 for a diagnosis.
Subaru may cover this out of warranty but you will have to drop your “humor”/style in this posting and be to the point. Don’t mention “on-line” prices.
I found in my 2005 Legacy one check engine light causes what you see in disabling ABS and cruise if the original code relates. Thankfully my cases was spinning the tires in deep snow caused an erroneous Vehicle Speed sensor code but cleared itself as dealer told me it would after I called.
Along with a number of other red flags in the original post the “I’m a big fan of conspiracy theories…” raises the eyebrows a bit.
My mechanic charges $80 for diagnosis but will usually knock that off the repair bill if I have him fix the problem he finds. Most garages around here are the same. The reason they charge the fee only to deduct it from the repair bill is to discourage people from coming in to get free diagnostics and then fix the problem themselves. I personally have no problem with this.
Guys, thanks for the comments. It looks like I’m the only guy who has had this experience on a 2010, which kills my conspiracy theory.
I’m still a bit concerned that my dealer is making hay at my expense, I’m fine with $350 for a sensor replacement, but $500 is starting to remind me of my old Mercedes dealership, where every repair started at $1,000…This is the first new car I’ve bought in a long time, I guess I expected at least two years without any problems…silly me…