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Throw some parts at it

I watched Motor Week last night. Pat Goss’s segment was on OBD-II scanners. During the discussion, he said that dealer mechanics frequently pull the codes, then change the first part that comes up rather than troubleshooting the problem. The dealer doesn’t want to pay for the diagnosis and just wants to “fix” the car, whether it works or not. I guess that’s another reason to get the scanner yourself or borrow it from the auto parts store. I guess he wouldn’t mention it unless it is an epidemic. Ain’t that some…stuff.

My Rivieras had built in diagnostic code readers but from that experience I can understand why sometimes its more pragmatic just to replace a suspected part. Also you can have several codes that are set from one problem and you have to work from the lower ones to the higher ones so ain’t so easy. Never had a dealer eat the diagnostics though since usually you pay a diagnostics fee and then go from there. I guess if you have all the time in the world like Goss does, you can check everything out in the circuit and test the components first but time is money.

None of that surprises me at all.
I’m not defending that car repair approach. The DTC’s Don’t Tell Which Part/Parts To Replace (Sometimes None Are Needed). They Lead One To A Particular System Or Circuit Or Advise That “Something” Is out Of Its Parameters.

However, I am guilty of buying and replacing a part or two based almost entirely on a DTC (usually accompanied by drivability or other symptoms) if it is very like to be a part issue (more likely with some codes than others) and if it takes a very inexpensive part and a difficult (or impossible for me) or expensive diagnostic procedure.

This often works for me and I can assure you I’m way ahead of the game with prudent use of this technique.

To employ the strategy 100% of the time is absolutely not very professional, even for amateur DIYers.

I have a good scanner and my daughter carries a code reader and knows how to use it. When she’s away at school if she ever had a problem I can help advise her by phone.

I often use the same technique on my cars and I too am ahead of the game with it.

I sometimes think that medical doctors use a similar approach by automatically throwing a prescribed medication at the symptoms without really diagnosing the disease. When I was a research design consultant, there was a programmer on our staff who would fix program by changing lines of code until the program functioned as it was designed to do
One time he volunteered to help one of my graduate students with her project that was yielding incorrect results. He began working on this program at 4:30 in the afternoon. I had two evening classes, one from 5:00 p.m. to 6:30 and the other from 7:00 p.m. to 9:30
When I got back to my office, he had the program running correctly, but his explanation of what caused the incorrect results didn’t make sense. I looked at the original code and the programmer had used the variable name TOTAL. However, at one point in the code, she had spelled the variable T0TAL. Notice that in one case the second character was the letter “O” and in the other case the second character was the numeral “0” . TOTAL and T0TAL represent different variables. When I looked at the original code and thought about the incorrect output, I found the problem in 5 minutes. IMHO, time spent on diagnosing a problem, be it automotive or otherwise is time well spent and I am willing to pay for this time rather than to throw parts at a problem.

I’m a firm believer in using a slash through zeros to differentiate the difference in O’s and zeros. I don’t know why this is not more widely used. I remember getting an updated nav program with O’s and zeros in the dang user code. I had to call them to figure out which was an O and which was a zero.

"IMHO, time spent on diagnosing a problem, be it automotive or otherwise is time well spent and I am willing to pay for this time rather than to throw parts at a problem."

I agree with you, if one is paying for the diagnoses and repairs.

However, for the DIYers it can be different story. I don’t have some of the very expensive and seldom used diagnostic equipment necessary for certain troubleshooting. Dealers have many of these tools. I don’t.

A DTC, such as P0455 could be a problem requiring a special “smoker” or other tools for proper diagnosis. It’s easy and relatively inexpensive and almost prudent to suspect a faulty sealing gas cap. Finding the gas cap on tightly, I have repaired this problem on my own car by simply cleaning and WD-40ing the gas cap seat on the fuel filler pipe. One can often fix this problem by throwing a new gas cap at it.

As I stated earlier, certain DTCs are more likely to be a part problem. If I have a vehicle and get a DTC for a certain O2 sensor and I know the car (200,000 miles) is way overdue for its replacement, and it’s relatively easy to access it, I would probably throw a sensor at it. Been there, done it.

1l I |
(one, lc L, uc i, vertical line)

don’t forget that an evap leak code doesn’t always mean that there is a leak

If the system can’t pull a sufficient vacuum, the pcm assumes there is a leak

a purge valve that is getting power and ground, but can’t pull a vacuum will lead to the same code

and a rotten hose going from the intake manifold to the purge valve will also lead to the same code

a code is merely the starting point, not the final answer

Several years ago I was having some tough health problems and spent several thousand dollars beyond my insurance coverage on tests that in retrospect seemed to be throwing me into a gauntlet of tests beginning with the most expensive with no regard to my specific complaints. I finally diagnosed myself as suffering from diabetes with the help of google and then spent $1,200 for an official diagnosis from a specialist after paying $120 for a referal from one of the incompetent doctors previously seen. The entire story would make a great condemnation of today’s healthcare system. I told 2 doctors that they would be very poor if their work were held to as high a standard as local mechanics.

Diagnosing a problem can be very difficult whether on a car or a person but the first challenge is to get to the bottom of the complaint and healthcare professionals seem more averse than mechanics to doing so. What does “it won’t crank” mean?

The reaction of some doctors at a service counter when told “we’re going to have to run some tests at a cost of…” or “the repair is going to set you back…” can be priceless too.

What if you couldn’t even tell the doctor at the service counter what it will cost?

If you really want to shock your doctor or nurse, tell them the actual cost of the tests they just ordered for you or the monthly cost of the patent drug they just prescribed instead of the generic. Or the huge difference in prices quoted by different test providers. (cardiac stress test - $688 from one lab, “about” $10,000 from the local hospital) Those of us on high deductible healthcare plans the real cost all too well.

At least the mechanic or service writer has a pretty good idea how much each parts change or repair will cost!

OK, enough of the doctor bashing. If you want to make comparisons then check the cost of med school and the number of years of lost income to become one. Then check the price of an MRI machine and the technicians that run it compared to Sun diagnostic equipment. Most of us just vote with our feet if we have bad experiences with health care providers or mechanics, and that’s how it should be.

Medical treatment is a blind item. The cost varies greatly from provider to provider. And the cost varies greatly depending on your health care provider. Each provider negotiates their own prices with the Doctor/Hospital.

I’ve never had a problem with my medical care nor am I dissatisfied with the prices.

Enough of the doctor bashing? Heck, I didn’t even start yet! In my lifetime, half of my visits to M.D.'s would have been better served by finding a veterinarian!

I know diagnostics. I worked in that field for my entire career. Diagnostic principles are the same for medicine; for automobiles; and for electronics. To diagnose medical, you need to know medical and anatomy and meds and diseases. To diagnose automotive, you need to know automobiles and failures in cars. In electronic diagnostics, you need to know electronic theory and failures.They all use the same differential diagnostic principles.

I was leery of OBDII when I first got it. Now, I love it. The testing principles of OBDII are the same as the so-called ‘self-test’ function on avionics equipments I worked on for over 30 years.

MRI’s are like $10,000 Toyota engine scanners. Must use at every opportunity whether needed or not, just to pay for them. Here in rural Mexico, there are no MRI machines. Trained ultrasound operators, a medical specialty here, are used successfully for mosts things that cost so much in the US on MRI. I was stunned when my doctor friend showed me the list he is authorized to do. An ultrasound costs around $25 USD here, and he can spot things like prostate cancer

I have two engine scanners. The first was a code reader/eraser. The second one is freeze-frame and can read sensors. My next one will be one of those with a graphing function for sensors. I have had a few people stop by for a free scan.

@irlandes I thought a veterinarian would be better than an M.D. until I realized how the veterinarian would take my temperature in a check -up. On a serious note, I really worry about whether we are teaching students any problem solving skills when we have all these statewide multiple choice exams in the school systems and so much time is spent preparing students for these exams.

Medical Patients And Cars (Owners Must Speak For Them) Can Provide Many Symptoms And Clues To Many Ailments.

However, many doctors and mechanics fail to properly garner these symptom/clues from the patient or car owner (or car itself), either because they don’t know how to ask proper questions, don’t take to time to listen, or in the case of cars, never talk to anybody except perhaps a totally clueless service advisor. They order up some labs, images, and tests, some are never used, some aren’t necessary (some doctors own an interest in these) and prescribe some medicine. Some mechanics throw parts at it.

I had the world’s best doctor/diagnostician until he retired. He could out-diagnose multiple lab tests and imaging scans. He could ask a brief series of questions specifically pertaining to a specific ailment complaint. Each answer triggered another question and he’d rule in or rule out possible causes and explain the process as he went along. He formed a flow-chart in his head based on knowledge and wisdom.

I asked for his help selecting a new doctor. His advise was to "make sure he/she was a listener."
I will say that I’m not sure his diagnostic ability is something taught to all doctors, nor possible for all doctors to acquire, even if they listen intently. I’m still looking for that individual.

I Can’t speak for all dealerships, but that kind of shotgun diagnosis will:

  1. On a warranty repair, result in a charge back by Ford. All work in a dealership is done flat rate, and virtually every procedure done to a vehicle has a defined time allotment that the technician is paid, including diagnostic time. Additionally, warranty costs of each dealership are compared with other dealerships of similar size within a particular region. If your warranty costs are much higher than those in your group because your techs are poorly trained and the dispatcher is assigning work to a technician not qualified to do that work, then expect a warranty audit from Ford in the near future.
  2. On a cash repair, if a tech is a shotgun mechanic, they are quickly weeded out by their inability to fix it right the first time.
    None of the dealerships I was employed in would assign work to a tech that was not trained and qualified to do the repair.

“In my lifetime, half of my visits to M.D.'s would have been better served by finding a veterinarian!”

That is undoubtedly because you never asked a hospital-based nurse for his/her recommendations. My best friend is a critical care nurse, and when I moved to this area and wanted new doctors, I asked him for recommendations.

No responsible nurse is going to say something negative about doctors if he/she wants to keep his/her job, but when I asked, “What do you think about Dr. X?”, he would simply say something like, “I think that you would probably prefer Dr. Y”. I am very happy with all of the doctors who he recommended, and I’m not sure that this would have been the case if I simply looked in medical directories.

As one example, several years ago, when Governor Christie experienced chest pains and breathing problems while he was in my town, he was rushed to the local hospital. According to my friend, there were at least 7 Cardiologists on duty at that time, yet the Chief Medical Officer summoned the Cardiologist whom my friend had recommended, in order to examine the governor. That entailed having my Cardiologist leave his office (about 1/2 mile from the hospital), but apparently the Chief Medical Officer felt that this slight delay was preferable to having any of the on-duty Cardiologists examine the governor.

The outcome was merely to prescribe an inhaler for asthma, and a recommendation for the governor to lose at least 100 lbs, so clearly there was no imminent coronary issue, but I find it interesting that the hospital’s Chief Medical Officer did not trust any of the on-duty Cardiologists to treat a very high-profile patient!

On a daily basis, nurses who are based in hospitals see which doctors screw-up on a regular basis, vs which ones have consistently good outcomes for their patients. Those nurses also observe which doctors treat their patients as sentient human beings with health problems, rather than as simply a source of income.

Try to get recommendations from a hospital-based nurse!

Edited to add:
When I broke my left foot several years ago, my friend asked the head nurse in the Orthopedic Unit for an Orthopedic Surgeon recommendation for me. He reported that, without hesitation, she replied, “Nobody from this place!”. Instead, she recommended an Orthopedic Surgeon at another hospital, and I was very happy with that recommendation.

The OBD-II system is to be used to help a good mechanic find the problem and that’s it. A lot of disreputable people use it as am excuse for “shotgun maintenance” and drive up the repair bill. In my mind those people are not mechanics and should be locked up. OBD-II is a tool and nothing more.