Took the Cherokee in for service b/c I have intermittently had error messages pop up re: the onboard phone (emergency 911, not bluetooth system), Engine start/stop system (which I hate anyway), a slow crank (ignition system issue?), and what feels like a slight misfire under load at highway speeds (MIL not on... yet).

Take it in for a looky-loo before anything gets worse and all I can get from the dealer is, "well, there aren't any fault codes active or stored in the system, so there's nothing we can do except some PM."

"What kind of PM are you recommending?" I ask.

"Coils, plugs, and air filter."

"I do my own air filters (which aren't due), the plugs aren't due for another 30K miles, and as for the coils, does it look like any of them are going bad?"

"No."

What a waste of money and time. Also frustrating that when HAL 9000 tells me certain systems aren't working properly, it doesn't generate an OBD code so problems, if intermittent, don't become bigger problems at less convenient times.

At some point, ASE certification is going to require a computer engineering background because apparently, mechanics can't mechanic these days unless the computer tells them what to do.

I guarantee I'll be back within the next month or two once a code is thrown.

-Rob

Those are the worst to deal with, I've had them on my HD, one was a faulty water pump, it wouldn't set the code but it'd flash the water pump lamp on the dash, by the time I"d get to the dealer the light would go out. Took several months for it to fully fail so it would be replaced.

They noted it in the files so it was seen as reported under warranty..

You are correct though the days of a generator, points and carb are long gone...

When you get done with your 18-24 months of full time classes to become an ASE certified master tech you can lecture the techs on what you believe they should be doing. Until then you all just sound ignorant and silly to us that have done the schooling.

quote:

Originally posted by Ryanp225:
When you get done with your 18-24 months of full time classes to become an ASE certified master tech you can lecture the techs on what you believe they should be doing. Until then you all just sound ignorant and silly to us that have done the schooling.

So when they literally tell me, "there's no code, so there's nothing we can do," how am I supposed to interpret that?

I'm blaming the unnecessary integration of every damned vehicle system into the ECM/ECU, PCM, TCM, BCM... and whatever else, for the tech's failure to have the capability to identify and correct a current issue. It's not so much their fault as it is they're being set up to fail by the manufacturers.

I have no doubt that if I brought them an old CJ Wrangler with a similar ignition and engine issue, they would be able to diagnose and repair it like champs - because they're mechanics, not computer engineers.

In point of fact, FCA will open "STAR" cases for problematic issues - under which a factory tech will get involved and work with the dealer's techs to resolve an issue. I've had to make that happen more than a couple of times when the dealer's guys were stumped.

-Rob

So you tell them how to find your problem. Where should they look first?
Would you walk I to an oncologists office and demand he cure cancer right then and there?

@ Ryanp225 SO you agree that he should change his plugs and coils

There are other tests that can be made, checking long and short fuel trims is one, I know some advanced techs that would use a scope and current ramp the coils. I wouldn't slam the entire industry over one location.

quote:

Originally posted by BigSwede:
@ Ryanp225 SO you agree that he should change his plugs and coils

AND the tires.

The rotational properties of the tires may be causing the 911 issue.

I used to do a lot of work for a large automotive school and it was discussed often that mechanics are nothing more than glorified computer tech who do nothing more than replace the parts they are told to replace.

Funny story.
Back when I was working on cars for a living, a customer brought their car in for a rattling noise when hitting a bump.
I test drove the car and the noise was obviously there.

Checked the trunk and there was a hefty bag filled with empty soda and beer cans.
We set the bag aside and when the guy came to pick up the car, we took him for a test drive. He was real happy.

He was a little embarrassed when we handed him his bag of cans though. No charge for that "diagnosis".

quote:

Originally posted by BurtonRW:

quote:

Originally posted by Ryanp225:
When you get done with your 18-24 months of full time classes to become an ASE certified master tech you can lecture the techs on what you believe they should be doing. Until then you all just sound ignorant and silly to us that have done the schooling.

So when they literally tell me, "there's no code, so there's nothing we can do," how am I supposed to interpret that?
-Rob

Rob, that's a great question.

Hopefully the shop has someone like rizzle that can come up with an add'l test.

quote:

Coils, plugs, and air filter."

"I do my own air filters (which aren't due), the plugs aren't due for another 30K miles, and as for the coils, does it look like any of them are going bad?"

My F150 has a slight stumble at low speeds, it's set no codes, even though I know it's there, others know, we all know, everybody knows, but, the BCECEIEIOM modules dont because it's not out of spec.

Research shows it's a coil problem 90%of the time, affects driveability at slower speeds. It's happened before, but eventually the bad coil revealed itself. Replacement cured it, and shortly thereafter replaced the plugs, because doing so on a 5.4 Triton is a PIA it went close to 100K on the OEM plugs.

See the 5.4 ford engine is famous for having 3 rings in the plug hole to screw the plug into that fail, sending coil and plug flying out, or just fail when changing. Nonetheless,,, if you let plugs get too old and weaker the coils have to work harder to create the spark, and that kills coils.

So maybe it is a coil going bad...

The multiplexer in your Cherokee would allow them to check where the possible fault lies in your U-Connect.

Count me as one of the few that work on their own vehicles and have an oscilloscope. Just about anything you need to know would show up. If you aren't running COP the O-scope would be where to go next.

Having a factory shop manual is a must.

quote:

Originally posted by Ryanp225:
So you tell them how to find your problem. Where should they look first?
Would you walk I to an oncologists office and demand he cure cancer right then and there?

Got news for you, I date back to Carburators and air cooled VW Flat fours. Back then if a customer reported issues such as an overheat light we would listen to the customer and ask pertinent questions. Then we would sit down with a pad of paper and list out all of the causes for an overheat issue. In the case of overheating you have a bad thermostat, clogged radiator, dirty radiator, slipping water pump and/of fan belt, low coolant level, etc. Then we would start checking everything on that list in order of Cost, low to high. BTW the cheapest item to look for is the physical condition of the radiator. I once saw a radiator full of road tar and chips because the driver was a hard core tailgator. Fix for that was a scrub brush and a bucket of kerosene, which I handed to the customer. When the customer started to complain I told him the only other option was a new radiator.

Point is that today's "techs" don't do any diagnosis unless a "code is throw" and that IMO is a flat out Lazy approach.

Now a bit of a test. What if you have an O2 sensor code set what are you going to do? Start by listing all of the causes for an O2 code.

My brother is an ASE Certified MM in several disciplines, but he's said many times that they're engineering the common sense out of today's vehicles.

I didn't take anything Burton said as a slam on the mechanics, but instead on the system that hamstrings them to an OBD reader and point and click manuals. Either make the system give a clear code when something is not working, or make it simple enough that we can go back to some degree of a rule out list that can be worked through.

BTW, I think the oncologist comparison is a bit off. More like going in to your family doctor. And he/she would get a list of ailments, run some blood, then have the nurse tell you nothing is wrong and charge the crap outta you. So yeah, maybe that works?

I've lost track of how many times I've taken a vehicle in because it ran rough, sounded wrong, vibrated, handled badly or didn't stop correctly, only to be told that the diagnostics don't show anything. Then a couple of months down the road what I had told them was a problem would show up on the computers. Maybe listening to an old gearhead who wrenched on his own cars and drove SCCA in his youth would be a good idea.

[QUOTE]Originally posted by slabsides45:
My brother is an ASE Certified MM in several disciplines, but he's said many times that they're engineering the common sense out of today's vehicles.

I didn't take anything Burton said as a slam on the mechanics, but instead on the system that hamstrings them to an OBD reader and point and click manuals. Either make the system give a clear code when something is not working, or make it simple enough that we can go back to some degree of a rule out list that can be worked through.
--------------------------------
I guess "slam" was a wrong term to use. Just be aware that there are techs out there that do go above and beyond learning systems in order to repair today's vehicles. They learn from expensive training classes ( Vision Hi tech training is one). There is so much technology in these new cars with adaptive cruise and avoidance radar, cylinder cancellation, etc.
The cars are easy to fix if there is a code set. The shops that can repair the no code drive abilities are out there, they usually open the hood and find many new parts. Someone made money on the parts, so now they get to fix it with time to locate the broken wire or mechanical issue.
The PM maintenance recommended in the original post for that model vehicle would most likely fix it.
Now if it were scoped with one bad coil, and only replaced one. Then another year goes by and another coil fails, you pay the diagnostics again.
So there are two sides of the repair, diagnostics has it's place after the parts have been put on. I don't really agree with that but with internet searches you can become a good parts installer and most likely fix it, especially if it has codes.
On a no code repair fuel trims alone will determine what bank, if it's a misfire from fuel or ignition, this is learned outside of most dealership training.
There are options out there when a shop says it can't find anything wrong without codes.

quote:

Originally posted by rizzle:
The PM maintenance recommended in the original post for that model vehicle would most likely fix it.

I agree. I’m certain that a coil will fail in the next couple of months. The problem is that unless a code is thrown OR they can diagnose a malfunction without a code, they’ll call replacement a PM issue and it won’t be covered under warranty.

-Rob

quote:

Originally posted by BigSwede:
@ Ryanp225 SO you agree that he should change his plugs and coils

I've got popcorn.

I don’t know if mechanics can’t mechanic, but some of them don’t seem to want to anymore. At least not at the dealership.

Just before we moved my 2008 Explorer had the check engine light come on. Almost all of my tools were already on a truck heading to FL and not wanting to make a 500 or so mile journey without investigating it, I bit the bullet and took it to the dealer.

They fixed the problem but when they sent the email confirming the repair they added a bunch of recommendations like “add brake fluid” and “flush and change transmission fluid”. The thing is I’d just done both. I went in and had a talk with the service manager telling him I knew the mechanic hadn’t checked any of that. The best part is that the coolant reservoir had a leak and was bone dry. There was nothing on the report about that so I knew the mechanic hadn’t actually done an inspection.

It turns out he didn’t. He didn’t check anything. The computer told him it the things on the list should be done based on mileage. Nowhere on the email did it mention that the services, another $1500 worth by the way, were based on mileage.