Burning smell

[KnightOwl]

When I first brought my car home I noticed a slight burning smell after a while highway driving. I thought at first it was just dressing the detalier had used under the hood to pretty things up, but by now I thought that would be gone.

 

I have looked closely under the hood and nothing is smoking in the slightest, and I've used a mirror to get a close look at the rear manifold to be sure oil isnt leaking from the valve cover, but everything looks clean.

 

Any other culprit ideas?

[bluegtp91]

Description on the smell?

 

How long has it been since they “dressed†or cleaned the bay?

 

Some of that cleaner stays in there for a hot minute.

[KnightOwl]

No clue how long the car had been cleaned/detailed before I bought it,(12/12/2017) but some things under the hood are still shiny (hoses, airbox) The smell is oil or plastic...like its cooking on the exhaust pipe someplace

[bluegtp91]

I'd cover up the alternator and air filter (if it's exposed, if not you're fine)...leave it running and take it to a car wash and blast the sh1t out of that engine bay.  Take the engine cover off as well.

 

See if that helps the cause if you haven't done that yet.  I'd check the exhaust though (maybe even the o2 harness to the manifold) to see if anything happens to be making contact.  Could even be under the car, too.  If it's stock the o2 in the U-Bend might be the culprit.  The harness is clipped up to the body and that could have came apart; thus laying on the downpipe.

 

Granted it's always hard to diagnose stuff over a keyboard...but that's what I'd do next.

[Grandprix1]

I’d be damn careful blasting water at stuff under the hood. But maybe that’s just me.

[Imp558]

I’d be damn careful blasting water at stuff under the hood. But maybe that’s just me.

 

I'm not.

 

I grab a 1/2 dozen cans of generic scrubbing bubbles bathroom cleaner from the dollar store and hose everything down with that stuff at the car wash, then just start the car and let it idle while I pressure wash it.

Things steam for like an hour while the pool on the intake evaporates.

[walterdude]

This might sound a bit weird, BUT.... One time in my 99 Lumina I had a burning smell and a little smoke I think... Turns out when I was parked at Costco the wind blew a plastic bag under my car and it melted onto the exhaust pipe... I could still smell it even when all visible signs were gone...

Good luck.

Tom B...

[vipmiller803]

I have looked closely under the hood and nothing is smoking in the slightest, and I've used a mirror to get a close look at the rear manifold to be sure oil isnt leaking from the valve cover, but everything looks clean.

I would check this and check again. Don't want another 3800 barbecue on our hands.

 

Ideas above are good candidates.

 

Stuck calipers can cause a smell on extended drives also. 

[Imp558]

Don't want another 3800 barbecue on our hands.

 

I just ordered Valve cover gaskets for the SSEi lol. Starting to catch a whiff with harder braking.

[bluegtp91]

I’d be damn careful blasting water at stuff under the hood. But maybe that’s just me.

 

Been doing it for a long time.  On MANY cars.  I'm not telling you to stick a pressure washer point blank to the entire engine compartment; just be smart about it.

[Imp558]

 I'm not telling you to stick a pressure washer point blank to the entire engine compartment; just be smart about it.

 

Seriously, lol, I literally do that routinely. I don't spray a battery, electrical center or alternator directly though.

[KnightOwl]

Seriously, lol, I literally do that routinely. I don't spray a battery, electrical center or alternator directly though.

I honestly think that's exactly what was done to the car because I've NEVER seen a car that old SO clean under the hood. The plastic bag thing could easily be a thing...I need to get the car on a lift anyway to check things out.

[bluegtp91]

Seriously, lol, I literally do that routinely.

 

I'm hoping that I'm not the only one that just imagined someone standing on the core support just hammering the engine with a pressure washer at the car wash, while yelling things.

 

Classic.

[Imp558]

I'm hoping that I'm not the only one that just imagined someone standing on the core support just hammering the engine with a pressure washer at the car wash, while yelling things.

 

Classic.

 

That's not far off the mark, and bathroom cleaner bubbles getting blasted around.

[KnightOwl]

ROFLMAO!!!

[Imp558]

It works awesome, we had a barrel of commercial cleaner at my old shop in the pressure washing bay but nobody used it. We would get cases of bathroom cleaner from the dollar store.

[Grandprix1]

Don’t get me wrong I use one to clean mine and you could preform surgery in my engine bay with how clean it is. But just blasting things with water doesn’t sound like a good idea. I just use a very light spray

 

 

Sent from my iPhone using Tapatalk

[KnightOwl]

I don't think the water will really hurt anything just spray since the vehicle is designed to withstand harsh weather conditions. BUT, I do know any kind of cleaner with the same active ingredient as 409 is bad JuJu...that stuff attacks wires and make plastic insulation go crusty. Not to mention staining the dickens out of anything polished aluminum.

[WarMachine]

Leaking valve cover, maybe exhaust leak.

 

 

 

Don't blast water onto your engine if you dont know what you're doing. You'll end up with a smelly car that doesn't turn on.

 

 

 

Like my old dodge. seriously f that car

[KnightOwl]

If I recall, I thought I started smelling something burning...right before the cat plugged up

[bluegtp91]

Well, that's the rotton egg fun time scent.

 

Common GM thing.

 

What you might have now is a plugged up resonator or muffler/s.

[KnightOwl]

I know when the cat plugged on the 2001, the power tanked and the engine kept heating up...it was pretty sick puppy. I've never heard of a resonator plugging but I can see it happening behind a carboned-up cat.

 

 

Might have to move exhaust mods up on my list.

[bluegtp91]

Get the car up in the air and look at it.

 

Another way to find out is to clean everything underneath it...drive it for a couple days, get it back up in the air and see if anything shows up on the surfaces you cleaned.  It might be some fluid hitting the exhaust, too.  Maybe PS or Tranny fluid hitting the exhaust as well.

[Imp558]

No chance of burning coolant smell? I'm assuming you know already but the coolant elbows frequently leak.

[KnightOwl]

No chance of burning coolant smell? I'm assuming you know already but the coolant elbows frequently leak.

 Yes, I've looked closely around the UIM several times and around the water pump area. The elbows appear to be fine, but if I pull the LIM this summer it will get the aluminum elbows from ZZP

 

I need to get the car on a lift and look around underside... not sure where I can tackle that though