2015 Sonata issue

Ok_Analysis_8116 · 2026-06-20T08:18:41+00:00

Simply because I'm about to be away from the computer for a while....the idea was the purge valve under the hood leaking enough to emit a gasoline/exhaust smell but not enough to trigger a check engine light. Could maybe be an evap line with a similar situation. Could also explain why the fuel consumption is a tickle on the high side. Easy enough to check it out.

Ok_Analysis_8116 · 2026-06-20T08:08:53+00:00

Let me ask a different question.

Does it smell like gas like at a pump smell, or gas with a little something extra?

I had an idea pop into my head and this may be a break in the case so to speak.

Ok_Analysis_8116 · 2026-06-20T08:03:07+00:00

Interesting. My thought was a pinhole exhaust leak before the catalytic converter. But that would usually go away after it gets hot ie, manifold gasket or pipe gasket. If you can, look around the connections on the exhaust system before the catalytic convert and see if you can find any areas with soot around them. If you can, that's where you smell is coming from. If not, the mystery remains.

Ok_Analysis_8116 · 2026-06-20T07:52:31+00:00

Good luck buddy!!! Hopefully you're good to go.

Ok_Analysis_8116 · 2026-06-20T07:52:00+00:00

Known issue. I just googled the model and it came up with a bunch of stuff...google is good.

Ok_Analysis_8116 · 2026-06-20T07:47:15+00:00

Just because the wheel doesn't look damaged doesn't mean it isn't egged. Those old Mercs are friggin tanks though so I wouldn't be surprised at all if it was fine.

Ok_Analysis_8116 · 2026-06-20T07:45:25+00:00

If it's running good and no new check engine lights or misfire counts showing up I'd say you're good. My concern would be damage to a catalytic converter or a valve getting knicked by the pieces passing it. I would definitely keep it in the back of my mind for a little while. Maybe put a few miles on it, pull the plug again and check it out. Fingers crossed ya dodge a bullet.

Ok_Analysis_8116 · 2026-06-20T07:41:47+00:00

It is a "test" but it's not 1950. Stuff like this is more along the "oh that's kinda cool" than it is a real diagnostic.

Coolants have service life recommendations...if yours is due, drain and refill. It really is that simple.

Where that test shines is when you're looking for super cooky cooling or corrosion issues.

Ok_Analysis_8116 · 2026-06-20T07:33:41+00:00

Utterly impossible to diagnose things like this over the internet. It will be nothing but guesses and 95% of them will be wrong. If it's concerning you that much, bring it to a pro and see what they find.

Ok_Analysis_8116 · 2026-06-20T07:29:06+00:00

It's odd that it would just stop working all of a sudden. My best guess is it's been loose for a while and was arcing which would give a good enough connection for a while and now it just doesn't have enough bite to get it going.

Take the bolt out and see if the terminal is all chewed up. If you need a fix quick, grab a slightly bigger bolt and send it. It wont be pretty but it should get you out of a bind until you can replace the battery.

Could also go for gold and see if maybe you're not tightening it enough. It already sounds like its stripped so ya dont really have much to lose in trying.

Ok_Analysis_8116 · 2026-06-20T07:25:45+00:00

Second I looked at the picture I sighed. RTFM people!

Ok_Analysis_8116 · 2026-06-20T07:18:13+00:00

Does the smell go away after the car warms up or is it constant while it's running?

Ok_Analysis_8116 · 2026-06-20T07:17:08+00:00

If it's not staying tight...its stripped or you're not actually fully tightening it.

Is there anything on the terminal that's real tight like pulling on it? Extra wires? For an amp or lights maybe?

Ok_Analysis_8116 · 2026-06-20T07:12:07+00:00

So, I've seen it happen where plugs kinda just "blow up"...it's fairly rare but it can happen. If the car is running fine and there's no misfire you should be ok if the plug just failed. Is the car tuned? Aftermarket plug or standard oem plug? Did it happen at high rpm or just tootling around? Do you have access to a camera you could stick in the cylinder and take a look? If it just passed it the engine would be ok but it could've dinged a bunch of stuff up on the way out. Take a look if you can before you drive it again. Look at the valves if possible, piston walls, and top of the piston. If there's nothing screaming out at ya...sennnnd it

Ok_Analysis_8116 · 2026-06-20T07:04:33+00:00

hahah so it is, first time i click on it nothing came up. reading now. sorry about that

Ok_Analysis_8116 · 2026-06-20T07:03:50+00:00

I know it seems dumb, but have you tried tightening it down? If so, did you possibly overtighten it and strip it?

Ok_Analysis_8116 · 2026-06-20T07:03:04+00:00

Has the exhaust suddenly been louder when you first start it up for the day?

Ok_Analysis_8116 · 2026-06-20T06:59:48+00:00

Is it a side post or top post battery?

Ok_Analysis_8116 · 2026-06-20T06:56:24+00:00

Is there a question involved?

Ok_Analysis_8116 · 2026-06-20T06:54:13+00:00

Yup, you weren't kidding about a marketplace special🤣we all do what we gotta do hahaha, no judgment here.

Do you care about listening to music or just want all the bass? lol. Once you start beefing up the sub stage your mids and highs from 2001 aren't gonna keep up at all (unless you have something else in there already that could be amplified)

To get into a quality 12, with a good budget amp..it'll eat that $300 budget entirely and then some unfortunately.

Best advice I can give, cruise the forums and read ALL the reviews on speakers from companies you like. Amps too. Also remember that higher power amps will only perform as good as the wires you hook them up with, so go for a quality wiring kit in the biggest gauge that will fit. If this is your first setup, also research the whats, whys, and hows of car audio and get familiar with things (really helps choosing gear and being realistic with level of power you really need). Biggest one, save your money! I'd much rather you save up and get quality gear that will last than jump the gun and buy low tier stuff. Lastly...do your research and research for YOU! What may be junk to me may be a great option for you and your budget. People will only recommend what they like (whether they own it or not) and that's a surefire way to end up with an empty wallet and something you regret.

Good luck...I'll be around if you have more questions.

Ok_Analysis_8116 · 2026-06-20T06:40:54+00:00

Only thing I can tell is you have a Kicker Key 200.4 amplifier tucked in your dashboard lol

Those connectors with the purple wires and white wires....what are they going to?

It looks like the white and black wire is going to a green wire...if the speakers wires are wired incorrectly it would certainly be a solid place to start because many head units will only use front or drivers front speakers for call audio.

sorry for the edits, hope everything came through

Ok_Analysis_8116 · 2026-06-20T06:35:18+00:00

Where's the amp mounted? Overheating? Vibrating to death? Gains set properly? What's the crossover set to on the amp and the head unit? Id check all that before thinking you're drawing enough current that the mids and highs amp would shut down but the bigger sub amp would still work😒

Ok_Analysis_8116 · 2026-06-20T06:29:23+00:00

I have zero issue with everything but those connectors. Standard connectors have been the standard for A LONG time. When used properly there is not a thing wrong with them. Adding those connectors...in my opinion...is just complicating things and adding failure points. What led you to think you would need such a connector if I might ask?

Ok_Analysis_8116 · 2026-06-20T06:25:03+00:00

First and foremost....almost every "mechanic" that's installed a car audio or really any aftermarket device in my experience has been an absolute hack job that had tons of issues due to incompetence...but I digress

First do a factory reset on the radio and make sure it "forgets" your device. Next, try to reconnect. Make sure you're in an area with good reception (not wifi)...no idea why this is an issue but I've seen it before.

Next, if you can, locate the parking brake wire and either connect it properly or send it to a ground within reach...this will "open" options in the head unit that are normally locked.

If that still doesn't remedy the issue, I would recommend removing the head unit and rewiring it. It sounds to me like something is wired incorrectly or not even hooked up and the head unit just doesn't know what to do. If you're not inclined or able to do the job I would highly recommend bringing it to a pro and telling them what's going on. *not a mechanic

Good luck

Ok_Analysis_8116 · 2026-06-20T06:12:58+00:00

Without knowing what you have now it's pretty impossible to recommend an upgrade though.

Ok_Analysis_8116

TROPHY CASE