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Okay. Full disclosure. I am a retired automotive engineer. I spent 28+ years working directly or indirectly on automotive engine management systems, from the days prior to fuel injection up until the middle of the past decade. While not working on diagnostic procedures or software directly, I was constantly “rubbing elbows” with those who were.
First, BY FAR, the most important tool is the thing between your ears and the knowledge, from training or experience, that you have in it ! You have to have excellent basic knowledge the 4 stroke engine (suck, squish, bang, blow) and what it take to run (fuel, air, spark) and what it take to make it run right (the proper amount of fuel, the proper amount of air and spark of sufficient “quantity” at the appropriate time). If you don’t have an excellent command of these basics, forget it.
What I am saying is that diagnostics today and in the foreseeable future, will (in most cases) not pinpoint the exact part to replace (best example is a lean condition; dozens of things can cause it). It is only the proper interpretation of the “data” (codes, visual inspections, voltage/resistance readings) by a human being, plus addition “data gathering” (validating that the repair procedure resolve the issue) that will result in satisfying the customer, even if it is yourself.
Now having said all that, I’m going to off a bit on a tangent.
Repair places that charge the customer for “pulling codes” are, IMHO, “ripping off” the customer. Pulling engine/transmission/ABS/dashboard/infotainment codes should be a a “courtesy” to the customer. I would suggest that it be done by the service writer. I might accept a “small” charge to be waived it additional diagnostics/repairs are performed. And based on what I previously said, a service writer may only be able to say, “You have a lean condition. Additional ‘hands on’ diagnostics are required at $XX/hour.” The customer may not like this but it is honest.
I question the “value” of expensive tools, from simple wrenches to advanced diagnostic tools. Are they really worth it ? Or to say it the other way, do they make the mechanic that more efficient and therefore reduce the cost to the customer ? I “twisted wrenches” for a living for very few years, but I have been my extended family’s shade tree mechanic for over 45 years. Would SnapOn wrenches make me a better/more efficient mechanic ? Obviously, “No !”. Could I get by with Harbor Freight tools ? Likely. Do you need a Fluke/SnapOn/Blue point DMM/DVOM. Even a pro can’t really justify their cost. (Get one with a rubber outer guard, you will use that. Buy or make up additional test leads/connectors. They can be more important than the meter itself.) I still have not found the need to buy even a simple code scanner, but I do understand that it is now a basic tool. I still question the value of any “advanced” diagnostic tool, except in large shops. $5,000, plus the cost of software updates, is a lot of coin for a small shop.
Okay. Full disclosure. I am a retired automotive engineer. I spent 28+ years working directly or indirectly on automotive engine management systems, from the days prior to fuel injection up until the middle of the past decade. While not working on diagnostic procedures or software directly, I was constantly “rubbing elbows” with those who were.
First, BY FAR, the most important tool is the thing between your ears and the knowledge, from training or experience, that you have in it ! You have to have excellent basic knowledge the 4 stroke engine (suck, squish, bang, blow) and what it take to run (fuel, air, spark) and what it take to make it run right (the proper amount of fuel, the proper amount of air and spark of sufficient “quantity” at the appropriate time). If you don’t have an excellent command of these basics, forget it.
What I am saying is that diagnostics today and in the foreseeable future, will (in most cases) not pinpoint the exact part to replace (best example is a lean condition; dozens of things can cause it). It is only the proper interpretation of the “data” (codes, visual inspections, voltage/resistance readings) by a human being, plus addition “data gathering” (validating that the repair procedure resolve the issue) that will result in satisfying the customer, even if it is yourself.
Now having said all that, I’m going to off a bit on a tangent.
Repair places that charge the customer for “pulling codes” are, IMHO, “ripping off” the customer. Pulling engine/transmission/ABS/dashboard/infotainment codes should be a a “courtesy” to the customer. I would suggest that it be done by the service writer. I might accept a “small” charge to be waived it additional diagnostics/repairs are performed. And based on what I previously said, a service writer may only be able to say, “You have a lean condition. Additional ‘hands on’ diagnostics are required at $XX/hour.” The customer may not like this but it is honest.
I question the “value” of expensive tools, from simple wrenches to advanced diagnostic tools. Are they really worth it ? Or to say it the other way, do they make the mechanic that more efficient and therefore reduce the cost to the customer ? I “twisted wrenches” for a living for very few years, but I have been my extended family’s shade tree mechanic for over 45 years. Would SnapOn wrenches make me a better/more efficient mechanic ? Obviously, “No !”. Could I get by with Harbor Freight tools ? Likely. Do you need a Fluke/SnapOn/Blue point DMM/DVOM. Even a pro can’t really justify their cost. (Get one with a rubber outer guard, you will use that. Buy or make up additional test leads/connectors. They can be more important than the meter itself.) I still have not found the need to buy even a simple code scanner, but I do understand that it is now a basic tool. I still question the value of any “advanced” diagnostic tool, except in large shops. $5,000, plus the cost of software updates, is a lot of coin for a small shop.
[quote=”Sparks4184″ post=61039]Other than what I call “JiggleItAlittleIt’ll work” principle, I’d replace both the lock cylinder on the steering column and get new keys for it. Rather than going to a dealer, to save some dough, take it to a good locksmith.[/quote]
Absolutely ![quote=”Sparks4184″ post=61039]Other than what I call “JiggleItAlittleIt’ll work” principle, I’d replace both the lock cylinder on the steering column and get new keys for it. Rather than going to a dealer, to save some dough, take it to a good locksmith.[/quote]
Absolutely !Good video. Lot’s of theory, all though some may not have grasped it all in the limited time frame you had for the video.
For “shade tree” mechanics or some one without a scope, one way to further diagnose this problem is to swap injectors, say between cylinder #2 and #3. In this case, you would have likely seen the bad wire sooner.
I found it odd that your buddy installed the attenuators when he knew that the back EMF voltage was clamped at 60V. All inductive loads (coil) connected to anything electronic have some way of clamping that spike to protect the drive circuit. Still, maybe the attenuators should be left attached to the scope at all times.
Oh yeah. Only one “s” in misfire ! 😛
Good video. Lot’s of theory, all though some may not have grasped it all in the limited time frame you had for the video.
For “shade tree” mechanics or some one without a scope, one way to further diagnose this problem is to swap injectors, say between cylinder #2 and #3. In this case, you would have likely seen the bad wire sooner.
I found it odd that your buddy installed the attenuators when he knew that the back EMF voltage was clamped at 60V. All inductive loads (coil) connected to anything electronic have some way of clamping that spike to protect the drive circuit. Still, maybe the attenuators should be left attached to the scope at all times.
Oh yeah. Only one “s” in misfire ! 😛
[quote=”twiggy02919″ post=60884]My Toyota Sienna uses the wideband sensor and it’s 4 wires. There is a decal under the hood with the vacuum routing and it indicates that it uses a “wideband” or “a/f sensor”.[/quote]
Whether it is a “wideband”, universal, O2 or egu, UEGO sensor is all semantics.The bottom line is the heater is not working on the original sensor and on the replacement.
Disconnect the harness (or carefully back probe the connector) and confirm there is Vbatt with key on, engine running at the 2 black wires.
[quote=”twiggy02919″ post=60884]My Toyota Sienna uses the wideband sensor and it’s 4 wires. There is a decal under the hood with the vacuum routing and it indicates that it uses a “wideband” or “a/f sensor”.[/quote]
Whether it is a “wideband”, universal, O2 or egu, UEGO sensor is all semantics.The bottom line is the heater is not working on the original sensor and on the replacement.
Disconnect the harness (or carefully back probe the connector) and confirm there is Vbatt with key on, engine running at the 2 black wires.
Possibly a “nit”, possibly not.
In the video, you said there there would be 12V at the harness with the “key on”. Some cars may not power up the heater circuit until “key on, engine running”.
Possibly a “nit”, possibly not.
In the video, you said there there would be 12V at the harness with the “key on”. Some cars may not power up the heater circuit until “key on, engine running”.
[quote=”EricTheCarGuy” post=35379][quote=”twiggy02919″ post=35325]My sister-in-law just had a similar code and had her sensor replaced- I believe it was an A/F Sensor not an o2 sensor. She gave me the old sensor to bring back to my lab to evaluate it and x-ray images show that the heater wires were open. Cutting the sensor open I co uld see that these wires were badly corroded.
Here is an x-ray pic. It’s hard to see but both wires thin down to nothing at the arrows and one of the wires lifted from the graphite heater element.
[/quote]
That’s darn handy. I wish I had one of those to play with.[/quote]
Don’t forget to order an electron microscope at the same time ! :silly:[quote=”EricTheCarGuy” post=35379][quote=”twiggy02919″ post=35325]My sister-in-law just had a similar code and had her sensor replaced- I believe it was an A/F Sensor not an o2 sensor. She gave me the old sensor to bring back to my lab to evaluate it and x-ray images show that the heater wires were open. Cutting the sensor open I co uld see that these wires were badly corroded.
Here is an x-ray pic. It’s hard to see but both wires thin down to nothing at the arrows and one of the wires lifted from the graphite heater element.
[/quote]
That’s darn handy. I wish I had one of those to play with.[/quote]
Don’t forget to order an electron microscope at the same time ! :silly:[quote=”Wrench Turner” post=55326]Q: what’s the deal on Honda transmission fluid anyway…. in class all they taught us was to send honda’s to the dealer because they use special fluid that nobody has… what’s the real story on Honda trans fluid..?[/quote]
Transmission fluid, especially automatic transmission fluid, formulation is truly a “dark art”. I’m not certain that even the OEM know the exact formula as many additives are blended in to make the transmission operate properly (less so on manual transmissions).Like Eric said, always use the OEM fluid, which is why I would never have transmission fluid changed at an independent shop unless they show you they have the OEM recommended fluid (check your owners manual) in stock and it is written on the work order.
[quote=”Wrench Turner” post=55326]Q: what’s the deal on Honda transmission fluid anyway…. in class all they taught us was to send honda’s to the dealer because they use special fluid that nobody has… what’s the real story on Honda trans fluid..?[/quote]
Transmission fluid, especially automatic transmission fluid, formulation is truly a “dark art”. I’m not certain that even the OEM know the exact formula as many additives are blended in to make the transmission operate properly (less so on manual transmissions).Like Eric said, always use the OEM fluid, which is why I would never have transmission fluid changed at an independent shop unless they show you they have the OEM recommended fluid (check your owners manual) in stock and it is written on the work order.