Check Engine Light Blues
September 9, 2006 4:48 PM   Subscribe

Why does my 2001 Toyota Sienna have the same check engine light, with the same code, two days after my $600 repair?

The codes are "system too lean bank one" and "system too lean bank two". The mechanic replaced two fuel filters to the tune of $658. Two days later (today) the check engine light went back on. I checked the codes and they were exactly the same!!

Did this guy rip me off? Misdiagnose? Did he just throw parts at the problem? And what should I do now? Should I go to the Toyota Dealership to get this taken care of once and for all? Did I spend all of that money for nothing?
posted by crapples to Travel & Transportation (7 answers total)
 
Well, obviously, if you're now getting the same codes, the underlying problem wasn't fixed. But that may not imply bad faith on the part of the mechanic that replaced your filters, although I think he probably did something else, too, for $658, or the filters are insanely expensive and hard to replace, which I don't understand, being that some parts places are asking only around $25 - $30 for similar aftermarket parts.

I'd begin trying to resolve this by presuming the shop you took it to is honest, and wants to fix the problem. And then I'd have a chat with the shop manager or owner, and see exactly what they did, and what they think may be needed to fix it, during which you calmly express your dissatisfaction, and ask for his help in getting a resolution. Unfortunately, a lean fuel mixture can result from a number of common problems, some as simple as a vacuum leak or defective fuel pump or fuel pressure regulator, and others as serious and expensive as a defective engine control module.

So, as with most diagnosis and repair issues, you need to be dealing with a shop that has the experience and equipment to take the diagnostic codes you are getting back to a root cause, without you spending more time and money than required. On the other hand, depending on your vehicle's mileage and condition, sometimes the best diagnostic procedure is exactly to replace potentially defective parts (and in the case of digital electronic assemblies, that's sometimes the only way). Look for ASE certified technicians at the shop you've been to, and give them a reasonable chance to deal with you as a callback. They may be willing to comp you further diagnostic services, and you may be able to pay for only comparable diagnostic services at a Toyota dealership, so that you have a chance of getting agreement about the repairs, before spending more than the diagnostic fees, from a couple of places.

The 2001 Sienna is built on the popular Camry V6 engine platform. It's a very, very common engine, and you shouldn't have any problem finding reputable shops to fix it. My own experience is that dealerships vary, but Toyota does a good job of factory training and monitoring service quality at its dealerships, and you generally get a pretty fair shake from Toyota dealer service departments. Ask around for recommendations in your area.
posted by paulsc at 5:37 PM on September 9, 2006


Maybe he just didn't turn the switch thingy back to it's original position. I've had it happen before due to a variety of reasons: eg: forgot, didn't know how, got thirsty. I'd call and ask the service manager about it.
posted by lobstah at 5:38 PM on September 9, 2006


Misdiagnose? Did he just throw parts at the problem?

Sounds like it. There are many possible causes of running lean. The injectors could be clogged up with crap. Or the computer could be incorrectly diagnosing the lean condition itself. Or the O2 sensors or air flow meter could be reporting bad data.

$658 sounds like a lot to change the fuel filters, honestly. I'm sure they had to drop the gas tank to change one of them, but I'd figure that to be more like ~$200 in work. I'm not sure what to tell you, except don't take your car to a dealer to get it serviced after the warranty is over. I'm also not an expert, but I believe some car repair does involve just throwing parts at it until one of them does the job.
posted by knave at 5:40 PM on September 9, 2006


I'm not sure what to tell you, except don't take your car to a dealer to get it serviced ...

Actually, this sort of thing is exactly why it can pay to go to a dealer rather than a general mechanic. They have the diagnostic equipment (which any decent mechanic also should these days) but, more importantly, they have detailed knowledge and experience with each individual model. They see the same sort of faults every day, they have access to the dealer network and manufacturer's knowledgebase, etc. They know, for example, that on one model this diagnostic code generally means low fuel rail pressure, on another it means a crook MAP or MAF sensor, while on a third it's common for both O2 sensors to die simultaneously.

Not to mention the fact that, if a dealer doesn't fix it the first time, you have a little bit more leverage available to go back and say 'so, you're not going to charge me labour this time, are you?'
posted by Pinback at 6:08 PM on September 9, 2006


Pinback: "Actually, this sort of thing is exactly why it can pay to go to a dealer rather than a general mechanic. They have the diagnostic equipment (which any decent mechanic also should these days) but, more importantly, they have detailed knowledge and experience with each individual model. They see the same sort of faults every day, they have access to the dealer network and manufacturer's knowledgebase, etc. They know, for example, that on one model this diagnostic code generally means low fuel rail pressure, on another it means a crook MAP or MAF sensor, while on a third it's common for both O2 sensors to die simultaneously... Not to mention the fact that, if a dealer doesn't fix it the first time, you have a little bit more leverage available to go back and say 'so, you're not going to charge me labour this time, are you?'"

Not to be argumentative in askMe, but my experience, especially with Toyotas, is that this is utterly false. The only benefit of going to dealerships is that they charge less if you're under warranty. It's a myth that they 'know more;' they have the same equipment/manuals/know-how that every other mechanic has, since all of that equipment is available to the public, and often less, since the better mechanics are usually the ones that can go private. They are sub-par shops added on to a different business to give the impression of better service. If you look around in any town of any size, you'll find mechanics who worked for the dealership until they realized they were getting screwed, and then started their own businesses, because dealerships generally don't compensate mechanics as well as private businesses do. A good mechanic knows the particularities of models and years; if anything, my experience has been that private mechanics know this stuff better. And you have just as much leverage to complain about bad service and demand better at a private mechanic as you do at a dealership.

I highly recommend, unless you're still under warranty, finding a different place to have your car fixed than a dealership. Shop around; you'll find something better. I've had Toyota dealerships do much worse than what you described. They only care about you if you've got a warranty.
posted by koeselitz at 9:50 PM on September 9, 2006


www.cartalk.com has a user rated lising of mechancs searchable by location.
posted by doctor_negative at 6:07 AM on September 10, 2006


Thanks for the advice. I realized that I made a mistake in my original question. I meant Fuel Sensors, not Fuel Filters. Hope that didn't throw anyone off too much.

I appreciate the feedback, though. It's a frustrating situation, but I think I'll start with the shop that did the work originally and ask them to back it up, then go from there.
posted by crapples at 6:29 AM on September 10, 2006


« Older Cluelss mom needs advice as her 14 year old buys...   |   Put a spring in my step! Newer »
This thread is closed to new comments.