'01 Buick Le Sabre SES Light On

You must be practically psychic to be able to diagnose this problem with limited information. Sure, throwing parts at a car is the preferred method of professional mechanics and a lot of folks on this newsgroup but I won't do that myself. I have to pay for the parts.

There's a practical reason for resetting the check engine light - to verify that the problem is not some random glitch. Change the thermostat and maybe the light wouldn't come on but that don't mean that's what caused the original problem.

I'm betting that you're one of those mechanics that answers the question, "Are you sure replacing the part will this fix the problem?" with a shrug. I give you the last word on this.

You seem to be particularly stupid when you say this:

"throwing parts at a car is the preferred method of professional mechanics"

When in fact, Steve W. has consistently advocated testing and collection of data as his preferred method of diagnosis. Like any competent mechanic learned a long time ago.

You've further compounded your mistake by pooh-poohing the utility of using information that is easily available through the OBD-II connector because, well, that's the problem, there really isn't any reason to throw out useful information.

You really should consider just stopping making yourself look any dumber, although at this point I doubt that is possible.

The only data collected that I saw was an error code PO128. All the other diagnostic was a fantasy of how he'd proceed if he had the car. If you read my post, you'll see that I recommended the OP get a cheap OBDII. Did you even bother to read my post? Feel free to spend your money on expensive diagnostic equipment. It's a great idea if you got the money to burn.

The code readers are great for reading the error codes - that's all. My mechanic won't fix an intermittent problem unless he can reliably replicate it. I'm in the repair business and I won't do shit like that either. That's all I gots to say about that. :-)

Then you need to learn how to read.

Here is the Original post

So in this post Bob says AZ told him these were the problems that could cause the code (but he didn't list the code)

Next post: As a reply to Tegger

So now we have an actual code. And the first post does show correctly the most likely problems to cause this code.

Your first resp>> >>>> That's all the print-out gives...and then the possibilities of >>>> fault.

And Bobs Reply : > After taking a trip the MPG is 20% or so worse...and I would need the > scanner to reset the fault. > I think I will change the stat ($8.50) and then the sensor ($18.50) if > needed.

So now we have a Code pointing at a possible problem. A symptom (poor gas mileage occurring while the light is on) And the probable repairs needed.

My response laid out how it is possible to use a REAL scan tool (not a cheap POS code reader) to diagnose the fault, and do it while the vehicle is there the first time. I also included checking a couple of other items that may cause a similar problem. IE a leaking injector could cause lowered mileage, or a fan relay stuck on which would keep the coolant at a lower temperature. Both of those are dead simple to check and might take 20 seconds.

I also said that if AZ couldn't pull OEM specific codes (which most of the low end tools won't). That it could still be a bad ECT, BUT since he stated that the temp gauge still worked, The likelihood of it being the ECT is much less. And what codes it would throw if bad.

So you want to tell me exactly how it is "throwing random parts at it" when I listed the two parts that could be the problem. And narrowed that further to ONE part?

Based on your posts you seem to think that a REAL scan tool is useless. Fine stay in the dark and don't bother using a tool which can make it

1000 times easier to accurately diagnose a problem, and give the customer the repair options on the first visit.

Fine.

When your customer comes here and tells me "I went to this guy who didn't even test the car just turned out the light and said to drive it, bring it back if the light come back on"

I'll be more than happy to have them as a customer.

Another great idea if you've got money to burn is to not properly diagnose the car. In other words, guessing, which appears to be what you're advocating.

That's why they're called code readers.

That's a really swell philosophy, but there are people who want their cars fixed, and are willing to pay a competent mechanic to guess. I was always honest with customers, and told them what the most likely cause was, but warned them that there could be multiple problems. At that point, they get to make the decision, and they know what they're in for. There's lots of people out there with lots of money, and they are willing to take a chance.

Sorry, but that's ridiculous, unless you're talking about dishonest "professionals". The only other situation is in new car dealers, which is where I spent all my working life. There are times when you must guess, but it's the factory that pays, not the customer. In fact, it's the factory that tells you to guess, or that guesses for you. Unfortunately, some of the mystery problems never get sorted out, and remain impossible to diagnose. That's life.

What's wrong with being upfront with the customer? "I don't know" is a refreshingly honest answer to a lot of them. And if their car is stalling about once every three months on the expressway at 70 mph, they will probably be very willing to pay for a guess.

You have clearly never worked as a mechanic, so you need to understand that some people here have.

Sounds like a GM Crank Sensor....

How about a Dodge Ram 2500 w360. Drive down the road and it's fine one second. Bucking hard enough to break your neck the next. Toss the scanner on and drive down the road. HMM that ain't right. That ECM isn't supposed to shut down on it's own.

Solution, new O2 sensors. They were heating up and shorting the signal line and the 12 volt heater feed. Was enough to shut the ECM down. Engine would buck, power drop would reset the ECM and rinse lather repeat....

The description I used as an example was an earlier CTS. It would do exactly what I said, with the factory helpfully adding, "with no driver input". In other words, it was impossible to duplicate. They found a workaround, but I don't think they ever found a fix. Some owners of those cars were pretty, uh, shaken when that happened. At least they would start back up immediately, but the average driver does not have the presence of mind to slip the car into neutral, and quickly restart it, without losing too much speed. It seemed there was always a semi on their back bumper when it happened...

And now that I think of it, it was a bad example to use in this thread. You could throw every imaginable part at this problem, and none of them would have fixed it.

Don't you just love those helpful hints...

One sure repair, Different vehicle. Which line dealer were you with?

Always GM, Caddy for the final 10 or so years.

Ahh a deathstar tech.... Good to know. Used to be quite a few dealer techs on here. Think most left because of the BS and the lack of good access anymore.

You're right that I have never been a professional mechanic. I don't have any problems with diagnosing car problems - with or without a code reader so what's your point? Saying that I need to understand that there are people here that have worked as mechanics is pretty patronizing. It's obvious that this is the case but I still won't go out and spend a lot of bucks on diagnostic tools even if the expert here says I really, really, should. Does that mean I'm a bad person? :-)

I don't know if you're a bad person but you're an inarguable proven idiot who can't so much as diagnose a bad thermostat.

I changed the stat yesterday and it is heating-up much better...but I haven't taken it to get the fault reset (it's -20F here!)*L* Thnx!

-20, Ahh T-Shirt weather.... Must be global warming hasn't hit your place yet...

You probably should learn to not take things so personally and respect the opinions of others more. :-)

Really, You attack ME and say that I don't know what I'm doing. That my methods are useless, That I would just throw parts at a job and I need to not take that personal?

I don't respect ANYONE till they earn it. So far you haven't earned any respect.

You're taking this personally. My remarks were not directed at you. I don't know you or anything about you except that you don't care for my ideas on code scanners. Why this would be of concern to you is a mystery.

Bill Vanek wrote in news: snipped-for-privacy@4ax.com:

This is true. In fact, he even had special prison camps for folks who bought a scan tool.

Pol Pot never did figure out what was wrong with his 1975 Hochy Min.