....and it continues! -- P0306 Misfire.

[goodfellow]

I can't catch a break on the weekends these days. Which makes me glad I'm retired, but "for Pete's sake", every weekend a new problem with the family's cars seems to arrive at my doorstep. This time my daughter's Highlander flagged a "Check Engine" light and a "VSC" (Vehicle Stability Control) light while driving home from work last evening.

This morning I drove the car around the neighborhood and it definitely had an ignition miss. I then pulled the codes and found a P0306 - misfire (cyl. 6 misfire) and did the usual test by checking plug conditions and swapping coils between cylinders 4 and 6. Sure enough, after swapping coils between cylinders 4 and 6 the misfire moved to cylinder 4 -- bad coil. An easy fix with a new coil. Good to go!

The VSC problem was a brain teaser though. Long story short, after many other tests, the culprit turned out to be a faulty gas cap. Yup, a faulty gas cap set off the Vehicle Stability Control light. After doing some research, it turns out that Toyotas are notorious for indicating VSC issues even when there is no logical reason(s) for an actual VSC fault. The ECM controlled VSC logic must be very broadly defined to indicate a fault even when non-VSC subsystems are out of range.

Bottom line is that a VSC indicator light on a Toyota is a very strange event that could easily pull you down the diagnostic "rabbit hole", and potentially load the "Parts Cannon" with unnecessary repairs.

This is definitely something Toyota owners should be aware of  - 

[fatfillup]

Well done Ray.

If your daughter ever moves too far from you, she will be missing your expertise and low cost auto service

On the plus side, when she has children, they will be close and Mama will be happy

[goodfellow]

Well done Ray.

If your daughter ever moves too far from you, she will be missing your expertise and low cost auto service

On the plus side, when she has children, they will be close and Mama will be happy

Thanks Phil -- yeah, auto repairs have been free all her life, but to her credit, she appreciates it and takes me out to lunch or dinner at a nice restaurant every now and then. She also treats me to a box of my favorite cigars once in a while; which is really thoughtful.

[muddy]

The thing that tie into a computer or module these days is ridiculous.

On hyster forklifts with cabs they will code out if you disconnect the window washer pump

Sent from my Twisted Mind Of The Mudman

[bonneyman]

Good job, Ray.

I hate the way modern cars have become just rolling computer chips. Some years ago the Astro had a "slip" fairly often when taking off hard or travelling above 70 MPH. Nobody could find the problem, one even mentioned I needed new shocks and leaf springs to tighten up the rear end. Although I did get an ABS light quite regularly, But what would the ABS system have to do with the transmission shifting?
Come to find out on the Astrovan, 4WD versions have four individual sensors - one on each wheel. But 2WD versions (like my van) only the rear wheels have ABS. And the sensor is in the tranny! There's the connection. Pulled the ABS fuse - the shifting problem seems to have gone away. But I'd hate to run a vehicle that was designed with ABS without it.

[slip knot]

The dodge durango we had got a new fuel cap every few years. it would set off evap codes.

I watch Uncle Tonys Garage on utube. A while back he did a segment on a 2018 ford truck that the tailights got water in them and bricked the truck. IIRC it was over $5000 to repair. For tailights!!!

[goodfellow]

The dodge durango we had got a new fuel cap every few years. it would set off evap codes.

I watch Uncle Tonys Garage on utube. A while back he did a segment on a 2018 ford truck that the tailights got water in them and bricked the truck. IIRC it was over $5000 to repair. For tailights!!!

Holy crap! A taillight assembly did all that? That has to be the most FUBAR design that has ever hit the light truck market. Ford should be ashamed.

I had to google this POS taillight fault SlipKnot, and sure enough, this is a not so uncommon problem on high-end Ford F150 Series trucks. How stupid do these engineers think the public is? This is crazy! YouTuber FordTechMakuloco has a video on this very problem. ------ Crazy!!!!!

[muddy]

That's just insanity stupid. We need to go back to making people smart and not the vehicles. Back to basics for vehicles.

Sent from my Twisted Mind Of The Mudman

[stokester]

"YouTuber FordTechMakuloco has a video on this very problem."

That's one smart tech who knows how to use a scan tool and looks at it from a system standpoint.  The problem I always had at the Chevy shop is that many of these types of problems could take hours to find that corroded connector or terminal but if under warranty it was equally difficult to get paid for your time.

I don't need much more convincing to keep my 2005 F150 forever.

[fatfillup]

That's just insanity stupid. We need to go back to making people smart and not the vehicles. Back to basics for vehicles.

Well said Tim.  Basic vehicles especially if you hold on to them like I do

[Lookin4_67GalaxieConv]

That's just insanity stupid. We need to go back to making people smart and not the vehicles. Back to basics for vehicles.

Well said Tim.  Basic vehicles especially if you hold on to them like I do

Agreed.  One of my DDs is twenty this year, in '24 the other will be twenty.

[goodfellow]

That's just insanity stupid. We need to go back to making people smart and not the vehicles. Back to basics for vehicles.

Well said Tim.  Basic vehicles especially if you hold on to them like I do

Agreed.  One of my DDs is twenty this year, in '24 the other will be twenty.

I'm with you guys on this. Keep the old cars running -- whatever it takes.

Newest twist is that many manufacturers are now installing secured gateways into the car's network. Ostensibly it's a security measure to keep hackers out of your car systems, BUT in order for you to gain access to the car's bidirectional diagnostics and reporting features, you MUST pay $$ every time you want to access your car's network diagnostics. I think Stellantis has gateways in all their cars. The Europeans are not far behind.

Give it a few years and every manufacturer will have these "pay to play" gateways in their cars, and you will need their diagnostic software to do any real testing beyond generic OBDII.

DIY guys like us are loosing in this repair game at every turn. In a few years we won't be able to do anything but the most basic maintenance procedures.