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Question for car mechanics re: Check Engine Light coming on.

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March 13, 2023, 01:04 PM
HRK
Question for car mechanics re: Check Engine Light coming on.
quote:
Originally posted by 12131:
Drove back to Joe Myers this AM. They checked things out, but the CEL no longer illuminated while there. There was no leak. Apparently they didn't check the coolant reservoir the first time. Otherwise, it wouldn't have been near empty. But, they said I will need to replace the "transmission range sensor PRNDL SWITCH". The cost is $623, but I did not have this done, since the CEL is no longer on. What say y'all?



Did you tell them you had a CE light come on? Did they scan the ECU for codes? Those codes they don't just go away you have to purposely clear them, if it set a real code then it should be in the ECU.


For discussions sake the cap could need replaced, since it was right after refueling, I'd watch and see if it comes back.

Now if the code isn't there it was probably cleared, sometimes they are the result of something happening one time. Like a loose gas cap....

If it comes back on, go to any autoparts store and have them scan it and show you the code, they will tell you what it means and what part you may need. You are under no obligation to buy anything and I've not been pressured by the staff to buy something.

They can clear it if you like and then you watch to see if it comes back, if so then it's something to deal with.

Mine have all been emissions related or spark related.
March 13, 2023, 01:05 PM
ensigmatic
quote:
Originally posted by 12131:
I'm pretty anal about the gas cap and always made sure it's tight. But, you never know. The cap is original manufacturer.
One of my wife's vehicles had the CEL come on and it turned out the gas cap needed replacement.

Only way to know is a diagnostic.

Why, with all the stuff built into modern vehicles, they can't include a diagnostic display is another question.



"America is at that awkward stage. It's too late to work within the system,,,, but too early to shoot the bastards." -- Claire Wolfe
"If we let things terrify us, life will not be worth living." -- Seneca the Younger, Roman Stoic philosopher
March 13, 2023, 01:24 PM
Hamden106
I had a check engine light in my Tacoma. I popped into the dealer and the tech scanned and right away tightened the gas cap. No more check engine light. The last gas jockey didn't screw the cap all the way.



SIGnature
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March 13, 2023, 01:28 PM
Patrick-SP2022
I would check to see what codes are in the code history.
This might tell you about the original trigger for the Check Engine Light.

Unless the dealer erased the history.

The shop trying to sell you the "PRNDL SWITCH" sounds like a story to me. What reason did they give you for replacing that?

I'm right up 290 from you in Fairfield and have a Blue Driver scan tool we could use. for your Toyota. Let me know if I could be of help.




March 13, 2023, 01:51 PM
sourdough44
Yeah, a buddy with a good scanner would be helpful.

In the past here, Toyota, they have mostly been emission items.

Over 100k miles, plugs & a few other things done recently?
March 13, 2023, 02:08 PM
P250UA5
quote:
Originally posted by Patrick-SP2022:
I would check to see what codes are in the code history.
This might tell you about the original trigger for the Check Engine Light.

Unless the dealer erased the history.

The shop trying to sell you the "PRNDL SWITCH" sounds like a story to me. What reason did they give you for replacing that?

I'm right up 290 from you in Fairfield and have a Blue Driver scan tool we could use. for your Toyota. Let me know if I could be of help.


From Pg 1.
My offer is the same, have the BlueDriver reader. Handy little scan tool for a bit over $100. got mine as a gift.




The Enemy's gate is down.
March 13, 2023, 02:19 PM
Patrick-SP2022
quote:
From Pg 1.
My offer is the same, have the BlueDriver reader. Handy little scan tool for a bit over $100. got mine as a gift.


It is a useful tool. I keep it in my truck, and it has helped me out a couple of times.
Missed your post on Pg 1. Not intending to step on your offer to help. Smile




March 13, 2023, 02:44 PM
copaup
Check Engine is usually (but not always) related to emissions. Loose gap cap and bad 02 sensors are what it's usually been for me in personal and work vehicles. Get a code reader and see what it's throwing. Check the internet, some cars can pull their own codes.

Now if it starts flashing...
March 13, 2023, 02:55 PM
smschulz
quote:
But, they said I will need to replace the "transmission range sensor PRNDL SWITCH".
The cost is $623, but I did not have this done, since the CEL is no longer on.

What say y'all?

Q


You need to get a full scan report (with codes) first.
Compare the code to options of what to do.
Sometimes you don't need to do anything (annoyance) and other times it can be serious or lead to future problems.
March 13, 2023, 02:57 PM
P250UA5
quote:
Originally posted by Patrick-SP2022:
quote:
From Pg 1.
My offer is the same, have the BlueDriver reader. Handy little scan tool for a bit over $100. got mine as a gift.


It is a useful tool. I keep it in my truck, and it has helped me out a couple of times.
Missed your post on Pg 1. Not intending to step on your offer to help. Smile


Oh, no worries. I need to keep mine handy more often.
I just happen to work down the road from him, but you're probably closer more of the time.
Q's good people, so happy to lend a hand if possible.




The Enemy's gate is down.
March 13, 2023, 03:11 PM
Ryanp225
If you could get the code that was stored I can point you in the right direction. Most autoparts store can scan it for you or a $20 tool will allow you to pull them yourself. It's very easy.
March 13, 2023, 03:49 PM
1967Goat
My wife's CEL light was on for a good 8 months in her 99 4Runner. She went to the auto parts store, but would never remember to bring me the post it note with the code. Roll Eyes

It was the knock sensor. I replaced it 2 weeks before I sold it. I was dreading doing it, because it was a little involved. Replaced 2 sensors and the knock sensor wire harness. Damn sensors were like $290 each from Toyota. Bit of a PITA, but probably saved me a grand doing it myself.
April 15, 2023, 07:18 PM
egregore
It has been a month. So what, if anything, came from this?
April 15, 2023, 07:23 PM
BigJoe
Sometimes the seals on the gas cap weaken and will throw a code. It's a pressure thing. Happened to e once.


...You, higher mammal. Can you read?
....There's nothing sexier than a well worn, functional Sig!
April 15, 2023, 07:48 PM
Joe 5632
You said the CEL happened right after you got fuel while traveling and now it’s out. Probably did the same thing I did one. Traveling once I stopped for fuel before crossing a state line where fuel taxes made gas 60 cents more per gallon. Topped it off to full- full. When I got going the CEL came on. Turns out if you overfilled some gas will get into the vapor evaporation can and throw the code. After awhile the gas evaporated and the light went out. Haven’t ever overfilled it and never had the CEL come on again.
April 15, 2023, 09:11 PM
slosig
quote:
Originally posted by Krazeehorse:
quote:
Originally posted by architect:
Am I the only one who suspects that those "free scans" at an auto parts dealer are nothing more than a sales tool. "We're seeing a 'code 390' that means you need to buy this $400 frammistat, don't worry, we'll install it "for free," oh, and you probably need a new battery too."

That hasn't been my experience.

They are a sales tool, just as the free <I forget the #> point safety inspection we used to do when I worked in a garage while I was in high school was a sales tool. We only sold the customers what they needed though, and I suspect the same is true of most parts stores. Saved a lot of folks a few bucks. Would you rather we tell you that you need brake pads in the next couple thousand miles or come in when it is squeaking, the rivets have scored the rotors and you need new rotors as well as a brake job? Not everyone who is trying to sell you something is looking to cheat you. Yeah, I’m sure some are, but I doubt it is the majority.
April 15, 2023, 09:16 PM
Rick Lee
WTF would a near-min. wage auto parts store employee care or bother telling you the code is something serious to try to sell you a part he doesn't make a dime on? Most car parts stores don't do repairs, so they make nothing on that. The employees don't get a commission on selling you a part. I just don't get why they'd lie. All I need is the code. I can research the issue and repair steps myself. I have a scanner, but didn't have it with me the last time I threw a code. AutoZone did it and it was a code covered by warranty or recall and so I had the dealer handle it.
April 16, 2023, 02:26 PM
cparktd
"PRNDL"

Little side track here.

Years ago I heard Jerry Clower tell a PRNDL story.


First time he ever saw and drove a car with an automatic transmission.

He guessed that "P" meant parked because it was parked.

Then he speculated "L" was for leaving... tried it, that worked.

Wanting more speed he tried "D" for driving... tried it, that worked.

Still wanting even more speed he assumes "R" is for racing...

He says, Thats when all hell broke loose!



If it ain't woke... don't fix it.
April 16, 2023, 03:35 PM
.38supersig
Some manufacturers will utilize a sensor that reads the electrical properties of the coolant. If the coolant is being topped off with water only, the electrical threshold will fall below what the sensor is designed to register. This will trigger a MIL (malfunction indicator light illumination).

Also of note, the malfunction should be stored in the 'history' codes even after the condition reads as clear. Any decent scanner should be able to read 'current' and 'history' codes with ease.

You may also be able to read the sensor inputs in real time and compare them to the range that would have triggered the MIL.

Let us know what you find.




April 16, 2023, 04:30 PM
selogic
Amazing ..