Automotive

Can bad gas cause spark plugs to fail (weeks later)?

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  • Mar 1st, 2019 12:21 pm
Newbie
Feb 16, 2019
6 posts
2 upvotes

Can bad gas cause spark plugs to fail (weeks later)?

Greetings,

TL;DR: Mother charged $700 because dealership claims the gas she filled up two weeks prior was bad and damaged the spark plugs, so they had to be replaced (instead of being replaced under the extended warranty). Does that sound plausible?

I'm not a car mechanic, enthusiast (unless we're talking about Tesla, sorry), or have much knowledge beyond a grade 9 automotive class, hence I'm reaching out to this community and hoping you can set me on the right direction.

Earlier this month my mother's car (a 2016 Hyundia Elantra) wouldn't start (weeks after it's last gas fill up, though driven daily). She had the car towed to the manufacturer's service centre (dealership), they corrected the issue and left her with a bill for $700+, due to "bad gas". My mother paid extra for an extended parts warranty with the manufacturer when she bought the car, so when my wife and I heard about this, something didn't smell right. When we used to drive an ICE car, taking it into the manufacturer service centre we would almost always come out with a $700 bill after each check up, so we're intimately familiar with the scams these places pull (or at least the unreliability of parts in an ICE car).

We took a look today at the receipt and service detail that was provided by technicians that outlines the troubleshooting done, and determination of cause to try and understand how they came to the determination that it was bad gas, this is word for word what it says:
Tech Cause: verified, crank no start. remove plugs and clean and dry off. still no start. ground out plug and crank, spark is week. gds diag. pending codes for mis-fire #1 and #2. change out oil. and replace plugs. veh. now starts. veh. has contaminated fuel. needs tank emptied. and new gas.
Tech Comments: no start diag. 1.5
Now, like I said, I know next to nothing about cars. However, I'd say, I can find pretty much anything I'm looking for after a few visits to my most reliable friend - Google. Based on the description of the troubleshooting done above to me it sounds like the technician did the following:

  1. Verified car wouldn't start.
  2. Cleaned off the spark plugs.
  3. Car still wouldn't start.
  4. Diagnostic codes showing misfires on cylinders #1, #2
  5. Replace spark plugs, replace oil.
  6. Car now starts.
  7. Blame it on the gas?

Again, I don't understand all of the words in the description provided, but I'm assuming that #'d list more or less says the same thing? What doesn't make any sense is how they made the determination that it was bad gas. I see that they identified the spark plugs were bad (they cleaned them, but they still didn't work, so then they replaced them). They also replaced the oil for what reason I'm not sure. It appears the combination of replacing the spark plugs and oil, allowed the car to start -- I don't see the correlation with bad gas.

I started googling for things like "spark plugs bad gas", "damage bad gas causes", etc... To my surprise I was expecting to find stories of dealerships using this as a way to scam people out of their warranties, instead I didn't find much of anything, including any connection between bad gas damaging spark plugs. So I decided to search for "Hyundai Elantra Faulty Spark Plugs", now I did found a slew of results and videos of people showing how to replace spark plugs on a Hyundai Elantra .. nothing that jumps out and says they are explicitly faulty, but an odd amount of people talking about how to do it that would make me think these go wrong frequently enough to warrant the attention.

Another thing I noticed when searching bad gas, every occurrence of someone confirming they had gotten bad gas, they said they realized almost immediately, as their car stopped working or acting funny right after driving away from the gas station. So my mother driving with bad gas for 2 weeks, doesn't seem plausible.

Looking at this from what I've read so far, it looks like something that should have been covered under the extended warranty (spark plugs), wasn't and instead blamed on bad gas, so my mother would have to pony up $700.

Considering you guys are much more knowledgeable about these things, is the dealership right and it's a plausible explanation for the spark plugs failing, or does what I think happened happen?

P.S. Called the gas station where she had filled up prior to ask about the bad gas, see if anyone else reported the same, waiting for a call back from the manager next week.
25 replies
Deal Expert
User avatar
Feb 11, 2007
21246 posts
25711 upvotes
GTA
TLDR, very good chance dealer is scamming you out of warranty coverage. $700 is way too much just to change spark plugs.
Unlikely gas station will admit they sold you bad gas.
If the women don't find you handsome, they should at least find you handy.
Deal Expert
User avatar
Feb 11, 2007
21246 posts
25711 upvotes
GTA
BTW, extended warranties suck.



If the women don't find you handsome, they should at least find you handy.
Deal Fanatic
Oct 26, 2008
7022 posts
2907 upvotes
Victoria, BC
"Bad" gas in the form of insufficient octane might cause the plugs to overheat, but there would be visible signs of that when they inspected them.

Not likely that would happen anyway. Water or sediment in the gas happens occasionally, but as you say that would be evident much sooner in that 2 week period.

You don't mention the standard new car warranty, so sounds like that is no longer valid because of high kms - hence the motivation for getting an extended warranty.

Depending on what plugs Hyundai fits at the factory possible that they have reached their replacement interval at around 100k kms?

On the first few unsuccessful start attempts the plugs would have got fouled with raw gasoline. The service technician made that worse when he replicated the cranking no start.

As they cleaned and dried them off it sounds like they didn't think they needed replacing based on kms travelled.

Grounding a plug against the block and observing spark is a bit subjective, but have to give them the benefit of the doubt on that as new plugs immediately fixed the problem.

Changing the oil might be considered overkill, or just prudent given that some raw gas would have leaked down the cylinder walls.

So, how did they arrive at $700? This must be itemized in some fashion.

I would guess:
LABOUR
- perform verification of customer reported no-start condition 0.3hr...... $40
- remove spark plugs, clean and dry, replace, attempt to start 0.5hr..... $60
- hook up to diagnostic computer, flat-rate charge...............................$100
- use diagnostic codes to further troubleshoot 0.3hr.............................$40
- fit new spark plugs 0.5hr................................................................$60
- oil change service 0.5hr ................................................................$60
- road test 0.5hr .............................................................................$60

PARTS
4 iridium spark plugs ........................................................................................ $80
4 L synthetic oil ............................................................................................... $50
1 x oil filter ......................................................................................................$12
Shop supplies ...................................................................................................$38

Total: $600
Tax: $78

Grand Total: $678

The wording in the extended warranty may give them an out for the cost of new plugs and the diagnostic charges, etc. may be a customer responsibility regardless.
Hyundais may be competitively priced as new cars but they get you later.
Temp. Banned
Jun 18, 2008
5095 posts
4664 upvotes
Montreal
aaron43859436330 wrote: Greetings,

TL;DR: Mother charged $700 because dealership claims the gas she filled up two weeks prior was bad and damaged the spark plugs, so they had to be replaced (instead of being replaced under the extended warranty). Does that sound plausible?

I'm not a car mechanic, enthusiast (unless we're talking about Tesla, sorry), or have much knowledge beyond a grade 9 automotive class, hence I'm reaching out to this community and hoping you can set me on the right direction.

Earlier this month my mother's car (a 2016 Hyundia Elantra) wouldn't start (weeks after it's last gas fill up, though driven daily). She had the car towed to the manufacturer's service centre (dealership), they corrected the issue and left her with a bill for $700+, due to "bad gas". My mother paid extra for an extended parts warranty with the manufacturer when she bought the car, so when my wife and I heard about this, something didn't smell right. When we used to drive an ICE car, taking it into the manufacturer service centre we would almost always come out with a $700 bill after each check up, so we're intimately familiar with the scams these places pull (or at least the unreliability of parts in an ICE car).

We took a look today at the receipt and service detail that was provided by technicians that outlines the troubleshooting done, and determination of cause to try and understand how they came to the determination that it was bad gas, this is word for word what it says:



Now, like I said, I know next to nothing about cars. However, I'd say, I can find pretty much anything I'm looking for after a few visits to my most reliable friend - Google. Based on the description of the troubleshooting done above to me it sounds like the technician did the following:

  1. Verified car wouldn't start.
  2. Cleaned off the spark plugs.
  3. Car still wouldn't start.
  4. Diagnostic codes showing misfires on cylinders #1, #2
  5. Replace spark plugs, replace oil.
  6. Car now starts.
  7. Blame it on the gas?

Again, I don't understand all of the words in the description provided, but I'm assuming that #'d list more or less says the same thing? What doesn't make any sense is how they made the determination that it was bad gas. I see that they identified the spark plugs were bad (they cleaned them, but they still didn't work, so then they replaced them). They also replaced the oil for what reason I'm not sure. It appears the combination of replacing the spark plugs and oil, allowed the car to start -- I don't see the correlation with bad gas.

I started googling for things like "spark plugs bad gas", "damage bad gas causes", etc... To my surprise I was expecting to find stories of dealerships using this as a way to scam people out of their warranties, instead I didn't find much of anything, including any connection between bad gas damaging spark plugs. So I decided to search for "Hyundai Elantra Faulty Spark Plugs", now I did found a slew of results and videos of people showing how to replace spark plugs on a Hyundai Elantra .. nothing that jumps out and says they are explicitly faulty, but an odd amount of people talking about how to do it that would make me think these go wrong frequently enough to warrant the attention.

Another thing I noticed when searching bad gas, every occurrence of someone confirming they had gotten bad gas, they said they realized almost immediately, as their car stopped working or acting funny right after driving away from the gas station. So my mother driving with bad gas for 2 weeks, doesn't seem plausible.

Looking at this from what I've read so far, it looks like something that should have been covered under the extended warranty (spark plugs), wasn't and instead blamed on bad gas, so my mother would have to pony up $700.

Considering you guys are much more knowledgeable about these things, is the dealership right and it's a plausible explanation for the spark plugs failing, or does what I think happened happen?

P.S. Called the gas station where she had filled up prior to ask about the bad gas, see if anyone else reported the same, waiting for a call back from the manager next week.

Your mother's car didn't start.

So your mother crancked and cranked and cranked the car over trying to start it.

Your mother's continued attempt to start the car flooded it and soaked the spark plugs in raw gasoline. Tech thought a cleaning would be enough, clearly it was not. Replacing spark plugs was the right thing to do.

That raw gasoline also would have gone into the crankcase and contaminated your oil requiring an oil change. Oil change was the right thing to do.

Bad gas is definitely possible. you'll have to ask the dealer but the above is user error.

And BTW you bought a Tesla, Elon scammed you good the day you signed your papers. This is how Tesla welcomes you to the family. Enjoy.
Member
Apr 27, 2009
430 posts
320 upvotes
West Vancouver
Bad or contaminated gas can lead to fouled plugs which typically shows up as a rough running engine before getting to the engine will not start state. Also the fouling could take some time to develop and the contamination could be caused by water vapour condensation in the gas tank.

Not sure why the mechanic did not start the diagnosis with checking engine codes and also identified codes on the customer report.

If the mechanic thought there was contaminated gas in the vehicle they should have replaced the fuel filter and advised that the fuel system needs to be flushed and warned about potential fuel injector problems.

Items like spark plugs are not typically covered by extended warranties.

The problem could also be a combination of cold weather, old spark plugs as outlined in this article

https://driving.ca/auto-news/news/your- ... his-winter
Newbie
Feb 16, 2019
6 posts
2 upvotes
Thought I'd follow up.

Called the gas station, they confirmed they had received no other complaints of bad gas, and advised going back to the dealership that serviced the car.

Went back to the dealership, they claimed they dealt with 4-5 other cases of bad gas in the same 10 day period, and are aware of 3 other cases at other shops. Hoping they will connect me with the others that experienced the same bad gas issue.

Reaching back out to the gas station with this new information, hoping I can get somewhere, and get reimbursed at the end of the day.
Deal Fanatic
May 4, 2014
5217 posts
7141 upvotes
Toronto, ON
aaron43859436330 wrote: Thought I'd follow up.

Called the gas station, they confirmed they had received no other complaints of bad gas, and advised going back to the dealership that serviced the car.

Went back to the dealership, they claimed they dealt with 4-5 other cases of bad gas in the same 10 day period, and are aware of 3 other cases at other shops. Hoping they will connect me with the others that experienced the same bad gas issue.

Reaching back out to the gas station with this new information, hoping I can get somewhere, and get reimbursed at the end of the day.
Gas stations aren't just going to cut you a cheque. It'd be next to impossible to prove the bad gas all came from the same gas station, and ONLY from that station, even if you managed to contact all the owners.

The dealership isn't going to just hand over other customer's contact information to you.

It's pretty apparent you're being played by the stealership...
Deal Expert
User avatar
Feb 11, 2007
21246 posts
25711 upvotes
GTA
aaron43859436330 wrote: Thought I'd follow up.

Called the gas station, they confirmed they had received no other complaints of bad gas, and advised going back to the dealership that serviced the car.

Went back to the dealership, they claimed they dealt with 4-5 other cases of bad gas in the same 10 day period, and are aware of 3 other cases at other shops. Hoping they will connect me with the others that experienced the same bad gas issue.

Reaching back out to the gas station with this new information, hoping I can get somewhere, and get reimbursed at the end of the day.
Sounds like you aren't the only one being scammed by the dealer.
If the women don't find you handsome, they should at least find you handy.
Deal Fanatic
Jul 26, 2007
7579 posts
5272 upvotes
Toronto
If you had bad gas, they should empty out the gas tank (extra money for the stealership) and that would be more believable.
Newbie
Feb 16, 2019
6 posts
2 upvotes
er34er34 wrote: The dealership isn't going to just hand over other customer's contact information to you.
To be fair I've asked them to reach out to those other individuals that claim were also affected, and to let them know if they want they can reach out to me as I'm looking into this. They need not give out other clients information, they can instead give out mine which I've given them permission to do.

It would make no sense for them to shy away from doing that.

If the others all went to different gas stations, perhaps we go back to the dealership, if they all went to the same one, it's a pretty strong case against the gas station.

Power in numbers hopefully.
Newbie
Feb 16, 2019
6 posts
2 upvotes
peteryorkuca wrote: If you had bad gas, they should empty out the gas tank (extra money for the stealership) and that would be more believable.
They did, that was about $300 out of the $700 bill.
Deal Fanatic
Jul 26, 2007
7579 posts
5272 upvotes
Toronto
aaron43859436330 wrote: They did, that was about $300 out of the $700 bill.
Ah I missed that one on your post. Guess they covered their track.
Deal Expert
Feb 29, 2008
30106 posts
5547 upvotes
Montreal
Has anyone had a verified case of "bad gas" in a first world country of late?
Newbie
Feb 16, 2019
6 posts
2 upvotes
Bearspaw, AB - 2019 - 'You killed the car': Families complain of dead vehicles, thousands in repairs after station sold bad gas
https://www.cbc.ca/news/canada/calgary/ ... -1.4975682

Ottawa - 2018 - Ultramar offering compensation after fuel mix-up in Vars
https://www.cbc.ca/news/canada/ottawa/g ... -1.4500946
Deal Expert
Aug 22, 2011
41791 posts
30051 upvotes
Center of Universe
At any point before the car stopped turning over, did you mom feel any type of hesitation or studder when starting the vehicle?
This happened to me in a brand new vehicle, right after filling up at an out of town gas station and figured it was such, as I was able to reproduce the hesitation and studder one after another.

Drove the car down the highway very spiritly, from East to West a half dozen time until the tank was at half, filled up at the usual station and the studder lessened drastically.
After the next fill up, it was good.
Newbie
Feb 16, 2019
6 posts
2 upvotes
spyhero wrote: Which gas station and what is the name of the dealership?
This is in London, ON. Do you know someone else that may have been affected?

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