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Discussion Starter #1
Yesterday I noticed a hot/burning smell as I was sitting at a light, then again when I got out of my car at home. I popped the hood, and seems to be coming from the vicinity of the brake booster / firewall / cowl. Smells like kinda like melted crayons or rubber.

There is no smoke, and everything looks dry (aka no fluid leaks). I installed Eibach springs and new strut mounts over the weekend, but nothing else on my car changed.

Anyone else ever experience an odd smell like this?
 

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Discussion Starter #2 (Edited)
Well, found the source of the smell, and I guess it's a good thing my engine bay didn't go up in flames. The pic is where the battery cable goes through the firewall. The black spot is definitely the source of the smell. I guess it's somehow arcing on the body right there.

I'm now taking guesses and offers for fixes. My first guess is to try to create some space between the cable and body, and insulate it in someway.

Edit: This is not true! Read last post
 

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Regarding the discoloration of the cable, the positive battery cable on this vehicle is in identical condition which is probably attributed to dirt accumulation. However, that's not to say your positive battery cable is not arcing or overheating and needs to be replaced. If a repair is necessary, would replace the entire cable (92216221) and call it a day. However, replacing the cable could very well be treating the symptom versus the problem as some other underlying could be causing either condition to occur. At any rate, Jova007200 has a good thread going http://www.g8board.com/forums/9-stereo-electronics/273393-sound-insulating-deadening-project-starting-1-13-a.html detailing the sound deadening of the interior and, if necessary, would probably provide some insight on the removal of the old cable. Lastly, would continue searching for other possibilities of the smell in order to rule out other possibilities. Good luck
 

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If the cable insulation is rubbed through at that exact spot and arcing, that may well be the only issue. Depends on how bad the cable is damaged to determine whether you can wrap it or replace the entire cable.

Now if the cable got hot and melted due to some other issue, you have to address that issue as well as the cable itself.
 

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Discussion Starter #5 (Edited)
The smell is definitely coming from the cable. I can touch it, and my hand stinks. Further up the cable, close to the jump start lug (where it runs on top of the strut tower), it's also pretty dry/charred looking as well. I don't think it's actually melted yet.

I also noticed that the whine through the radio (which my car has always had), was a bit worse over the past few days, however reduces quite a bit as I reduce electrical load: turning off HVAC, unplugging phone charger, etc. All of this leads me to ground issues.

Going to start with the common issue on the battery ground.

Edit: this is wrong as well, but the ground issue is fixed!
 

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Right on and choosing to start with the grounds is a good step. Hopefully, whatever is causing the issue won't be too difficult to pinpoint.
 

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Discussion Starter #7
Did some poking around, and my alternator is putting out 15.3v. Seems a bit high. Checked via engineering mode and multimeter on battery. Before starting the car, the battery was at 12.3-12.4v.

Some digging on here, I see some guys reporting normal voltage output in the 15+ volts, but still seems high to me.

Does anyone have a schematic or description of how the battery lines run? Specifically, from the jump start lug into the engine bay. 2 cables come off of it, and hard to tell where the go. Looks like to the Fuse Box, and either the alternator or starter.
 

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The left one goes to the starter. The right goes to both the fuse box and alternator. By the way, the positive battery cable part referenced above goes from the battery to the positive stud located in the engine compartment.
 

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Discussion Starter #9
The left one goes to the starter. The right goes to both the fuse box and alternator. By the way, the positive battery cable part referenced above goes from the battery to the positive stud located in the engine compartment.
OK. Thanks. The split cable for fuse box / alternator was the confusing bit. And, yep, got it on the cable from the battery to the positive stud.
 

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Very well. Sitting in the driver's seat, reverse the above order to keep it in line with strict industry standards i.e. forum guru correction. :|
 

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Did some poking around, and my alternator is putting out 15.3v. Seems a bit high. Checked via engineering mode and multimeter on battery. Before starting the car, the battery was at 12.3-12.4v.

Some digging on here, I see some guys reporting normal voltage output in the 15+ volts, but still seems high to me.

Does anyone have a schematic or description of how the battery lines run? Specifically, from the jump start lug into the engine bay. 2 cables come off of it, and hard to tell where the go. Looks like to the Fuse Box, and either the alternator or starter.
The 15+ volts is when battery charging first starts but should taper down after a while. Check the voltage after driving it a while, it should come down.
 

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Discussion Starter #12
Well, managed to fix a lot of little problems by replacing my ground bolt on my battery cable. Old one in pic. Also ran a tap through the threads on the car, and a wire brush. I could at then see clean, bare metal again. Replaced the bolt and washer with a new one picked up from Homeless Depot. M8x1.25 x 20mm in case anyone needs to know.

My radio whine is now almost gone, car starts faster, lights are brighter, door locks work better. Lots of little things. I really underestimated this fix, and it was deceiving given the nice clean appearance of the top of the bolt.

I am however still getting the hot smell from the same vicinity. It seems to be lessened now, but I can smell it around the cowl, even with the hood closed. I ordered a laser thermometer, and will test stuff under the hood this weekend to see if I can better pinpoint anything.
 

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Discussion Starter #13
The 15+ volts is when battery charging first starts but should taper down after a while. Check the voltage after driving it a while, it should come down.
Forgot to add to my other post. Yes, it came down to the mid-14 volts. And actually, with the fixed ground, I never saw it get over 15v again.
 

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... Replaced the bolt and washer with a new one picked up from Homeless Depot. M8x1.25 x 20mm in case anyone needs to know...
Are they a new subsidiary of the well-known parent company? Kidding. A couple or so months ago, used a heli-coil to replace a thermostat housing bolt and it saved the day big time. Believe the bolt is either a M8x1.25x20 or 24mm.

...My radio whine is now almost gone, car starts faster, lights are brighter, door locks work better. Lots of little things. I really underestimated this fix, and it was deceiving given the nice clean appearance of the top of the bolt.
Good deal as it seems like you're well on the way to fully resolving the problem.
 

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Discussion Starter #15
Well,
1) I've been busy
2) I had to get over the embarrassment of figuring out the source of my problems. :| But what good are these threads without results.

Turns out I was completely wrong on my battery cable... Melted trash bag on your exhaust will indeed make one hell of a smell!!!

A heat gun aided in scraping off the caked on plastic, and the smell has been dissipating over the past week. As for thinking it was that cable, the smell was so overwhelming and it was the only rubber/plastic part anywhere in that vicinity, so I went for it. I can only conclude that the marks on the cable are in fact just dirt. As for it being hot, I guess it was just heat soak from being in traffic. Oh well.

OK, now you can laugh! :laugh2: And on the plus side, I fixed my ground issues! haha
 

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Well, it's innately human to occasionally misdiagnose things. At any rate, this happened on a customer's vehicle so told them to keep driving and eventually the smell would wear off. However, using a heat gun and scraping off the old plastic bag is a great way to expedite the process.
 

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Well,
1) I've been busy
2) I had to get over the embarrassment of figuring out the source of my problems. :| But what good are these threads without results.

Turns out I was completely wrong on my battery cable... Melted trash bag on your exhaust will indeed make one hell of a smell!!!

A heat gun aided in scraping off the caked on plastic, and the smell has been dissipating over the past week. As for thinking it was that cable, the smell was so overwhelming and it was the only rubber/plastic part anywhere in that vicinity, so I went for it. I can only conclude that the marks on the cable are in fact just dirt. As for it being hot, I guess it was just heat soak from being in traffic. Oh well.

OK, now you can laugh! :laugh2: And on the plus side, I fixed my ground issues! haha
I see your problem, the cats are still installed.. :D

Seriously though, glad you figured it out. I'm gonna replace the ground bolt on mine for the hell of it, I'm sure it's in need of it since I daily my car in most conditions.
 

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Discussion Starter #19
Awesome, at least the mystery is solved. And the repair didn't break the bank!
Free! Since I already owned the heat gun and scraper. :)

Well, it's innately human to occasionally misdiagnose things. At any rate, this happened on a customer's vehicle so told them to keep driving and eventually the smell would wear off. However, using a heat gun and scraping off the old plastic bag is a great way to expedite the process.
Yeah, I could barely stand to drive it anymore, the smell was that bad. That was also making it really difficult to diagnose because the smell was so strong. What pissed me off the most is that I remember running over the culprit. I'm usually diligent to make sure those things make it into my rearview mirror, but I was in bumper-to-bumper traffic that day and couldn't see the road behind me. So I forgot all about it. Took me running through every other possibility to have the, "sonuvabitch!" moment when I remembered the black trash bag. Oh well.

I see your problem, the cats are still installed.. :D

Seriously though, glad you figured it out. I'm gonna replace the ground bolt on mine for the hell of it, I'm sure it's in need of it since I daily my car in most conditions.
Haha! Yes, that they are, but they'll be replaced soon enough. DOD-delete parts are all ordered. Engine is coming out next month hopefully. Likely going with Kooks mids.
 
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