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A Mechanic's Life - Tales From Under the Hood

2811 messages,  Last post on May 19, 2013 at 7:34 PM

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Messages Page 85 of 282

#834 of 2811 Re: Pressured to not do your best [Mr_Shiftright] by isellhondas

Jan 16, 2013 (11:36 am)

Replying to: Mr_Shiftright (Jan 15, 2013 5:44 pm)
I think years ago in another forum we talked about the old Frantz filters that used a roll of toilet paper.
 
At the time they claimed you never had to change your oil again nor did you have to change your regular filter.
 
Just put a new roll of toilet paper every 2000 miles.
 
Anyone else remember those?

#835 of 2811 Re: Another tech posted this link [thecardoc3] by isellhondas

Jan 16, 2013 (11:45 am)

Replying to: thecardoc3 (Jan 16, 2013 7:22 am)
Yes, that was hard to read and sadly this reflects the way most techs still in the business feel.
 
When I was in the mobile tool business I often was able to recruit some quality people who were simply tired of making little money for working so hard.
 
Another factor to consider that it's a physically demending job. More so than most people realize and you don't see many guys working the line once they hit their mid 40's.
 
These same guys will often do their best to discourage the younger guys from going into the business.
 
I wonder what the Vo-Tech schools are doing enrollment wise.

#836 of 2811 Re: Another tech posted this link [Mr_Shiftright] by thecardoc3

Jan 16, 2013 (1:47 pm)

Replying to: Mr_Shiftright (Jan 16, 2013 8:44 am)
A sad tale indeed---although I do take issue with the one tech who blames the PUBLIC for his low wages! SAY WHAT?!!! The logic of that escapes me.
 
The fact that he is always free to quit being a technician and go do something else for a living his wages are his fault. Otherwise I do know what he is referring to.

#837 of 2811 Re: Another tech posted this link [isellhondas] by thecardoc3

Jan 17, 2013 (5:27 am)

Replying to: isellhondas (Jan 16, 2013 11:45 am)
I wonder what the Vo-Tech schools are doing enrollment wise
 
The school that I am teaching at last night and tonight isn't doing well at all. In fact the instructor there is planning on retiring at the end of this year and they don't even have a stong candidate to replace him. One of the other schools in the area is likely going to be giving up one of there instructors to fill the slot and their program is struggling so much that it can't place any of their kids into internships.
 
You can read the writing on the wall simply by looking at what is happening when it comes to maintaining the shops equipment, the superintendent won't spend any money on the shop, not a penny.
 
Heck come the end of the school year we might be looking for a location to hold our classes.

#838 of 2811 Diagnosing a misfire on a Jaguar by thecardoc3

Jan 17, 2013 (5:53 am)

If you go to my facebook page you will find a pressure transducer waveform from cylinder #2 on this car. Another shop sent it to me because it was setting misfire codes on all four cylinders on the RH bank, and they had already tested the compression, replaced all of the spark plugs and even swapped the coils and injectors side to side and nothing made a difference at all.
 
Using the pressure transducer it's very clear to see that the RH camshaft is retarded some 22 degrees causing in effect to much exhaust gasses to be trapped in the cylinders and that's killing combustion. In many ways it's like an EGR valve that is stuck open, which is why they misfired at idle, but under certain engine speeds and throttle openings, would start to contribute and the engine ran pretty strong. The diagnosis is the cam gear has come loose and is turning on the camshaft. Luckily this simply needs reset in time and hasn't done mechanical damage to the valve train.
 
I had another that car we diagnosed just before the end of the day tuesday. A 2005 Chevrolet Tahoe for the transmission stuck in first gear and the speedometer reading between 0 and maybe up to 6mph on occasion, but mostly just 0. Someone else had already been throwing speed sensors at it with no success. The testing was straight forwards, after confirming the reported issue and watching the scan data also showed no input (or at least incorrect input) from the VSS (Vehicle Speed Sensor) I disconnected the sensor and attached the oscilloscope and confirmed a good sensor output of some 12v AC peak to peak. When I re-connected the sensor I had 0v with the scope back probing the connection. That means that something is grounding the circuit and the voltage that the sensor is producing is simply not able to be seen by the PCM. To prove if it was the harness or not I disconnected the PCM and using channel B of my scope I connected to the VSS signal on pins 20 and 21 of the PCM's green connector. Now when I turned the wheels by hand I could see a signal from the VSS both at the sensor where it was back-probed and at the PCM's connector, and the two signals were identical. Reconnecting the connector to the PCM revealed no signal again. The grounding of the signal was confirmed to be occurring insde the PCM and it will need to be replaced to repair the vehicle.
 
The customer paid for the diagnostics and took his truck stating that he would be back later this month to have the repair done. I'll upload the VSS signal capture to my facebook page as well.
 
http://www.facebook.com/john.gillespie.127648

#840 of 2811 Re: Diagnosing a misfire on a Jaguar [thecardoc3] by thecardoc3

Jan 18, 2013 (3:59 am)

Replying to: thecardoc3 (Jan 17, 2013 5:53 am)
Gee, it got quiet in here all of a sudden.
 
 When it comes to high tech testing and diagnostic routines, using a pressure transducer like this is way up there, but it's not the only one that we(I) use on a regular basis. No doubt however this was something that is pretty new for everyone else here and many have likely never seen this demonstrated. All I can really say about that is there is a lot more where that came from and if you really think about just how much education and training, and experience goes into preparing to perform at the highest levels in this trade then we shouldn't have to deal with the perception that anyone can buy a cheap code puller and be ready to do our job anymore.
 
I did see an email that someone posted what appeared to be an add for a carbon cleaning system. No doubt adds like that deserve to be cut from here, too bad however that some of what would be mentioned in that add would be good information that needs expanded on, while some of it would deserve to have someone tear it up because of the misrepresentations that they often push. There have been many shop owners who have seen these systems advertised and been told that they can buy these machines, sell the services they provide and employ a less expensive technician to perform the services and make their customers happier. They push their sales pitches in a manner that suggests that it is state of the art training, so in essence the shop owners get scammed by many of these machine sales-people. The machines have their place in the shop, and there are vehicles that will benefit from the services they can provide but it takes a real technician to evaluate when it is time and make the proper reccomendation. The carbon cleaning machine is just another extension of "Can you put it on the machine and have it tell you what is wrong" myth. It's no different than pushing the idea that all you need to do is pull a code and you can know what part to throw at a car. Meanwhile top techs are using the kinds of tools and skills that the Jaguar required and the "experts" had no idea that it was even possible to do.

#841 of 2811 Re: Diagnosing a misfire on a Jaguar [thecardoc3] by steve_ HOST

Jan 18, 2013 (6:59 am)

Replying to: thecardoc3 (Jan 18, 2013 3:59 am)
Gee, it got quiet in here all of a sudden.
 
Well, when you said "The grounding of the signal was confirmed to be occurring insde the PCM and it will need to be replaced to repair the vehicle", I didn't think you'd appreciate being called a parts swapper.
 
The post about the car engine carbon cleaning system was from a gentleman from China and was removed for soliciting. I guess it's like the power flush push a while back (a way to flush one's wallet).

#842 of 2811 Re: Diagnosing a misfire on a Jaguar [steve_] by thecardoc3

Jan 18, 2013 (7:21 am)

Replying to: steve_ (Jan 18, 2013 6:59 am)
I didn't think you'd appreciate being called a parts swapper
 
LOL... The funny thing is he took the diagnosis and left. So who knows if I'll ever get to earn the full value of the effort that was provided.
 
The post about the car engine carbon cleaning system was from a gentleman from China and was removed for soliciting. I guess it's like the power flush push a while back (a way to flush one's wallet).
 
When performed for the right reasons, it is a valuable and necessary service. When it's done for the wrong reasons it is wallet flushing. JMHO.
The biggest problem however is when a third party without any real training and experience tries to guess as to whether it was properly advised or not.

#843 of 2811 Re: Diagnosing a misfire on a Jaguar [thecardoc3] by steve_ HOST

Jan 18, 2013 (7:26 am)

Replying to: thecardoc3 (Jan 18, 2013 7:21 am)
Twenty years ago people would just take their cars out to the highway and stomp on the gas and "blow them out". Seems like diesel owners still do that ("blow their noses").
 
Next up will be particulate capturing gizmos for gas engines similar to what's required on diesels now. That's fine, assuming the soot gets that far as combustion occurs in your engine.

Messages Page 85 of 282

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