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The mystery rattles and the short term smoke

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I know, it's old, it's rusty, and in general falling apart. But, it seems to run well.

 

 

Lately, I've been more nervous about the amount of smoke/steam coming from the exhaust. It's multiplied by the fact I have a huge hole in the muffler so it gets two places to come out of. I don't know if it's been the cold and I'm paranoid, or if I have coolant coming from somewhere, but it's only really smokey/ steamy in the first maybe minute of it being on, then it seems to settle down to a normal amount. Is it typical to be putting out more steam on start up on a cold day? Or should it be fairly even amount from start to normal operating temp? 

 

My other oddity, is something I just can't figure out. The car makes a rattling, as if a heat shield is rattling against something, but only on acceleration, above about 2k rpm. When I'm keeping steady speed, there is no rattling. It also doesn't rattle when I am stopped, but rev the engine, it's only when I'm moving forward. I looked under the car and I can't see anything that could make such a racket dangling down and sitting against something. The engine sounds perfectly fine otherwise, as I had thought maybe something was off.

 

And ideas? What might be loose, but not affect the driving? It drives fine, and there's no loss of power or engine struggles. It's not tappets or lifters because it's much louder than those.

Dead cat converter. When these break up internally they can rattle around under load. Give it a gentle tap and listen for rattles.

 

As for steam if it's cold weather you will naturally see vapour out the exhaust until the engine and exhaust pipe has heated up properly. At least that's how it works down here. I know in some parts of the states the exhaust always gives off vapour in winter due to how cold it is and the exhaust pipe not getting up to full temp.

 

If you've got coolant in the cooling system and your exhaust smells like something sweet but not right sweet you've got a coolant leak into the combustion chamber which usually means a head gasket.

 

Cheers

 

Bennie

Edited by el_freddo

  • Author

Alright, well the cat is newer, but wouldnt it rattle still even if I'm not moving? It's such an odd time that it rattles. Only when driving, and only while accelerating, over 2k rpm. But if I'm cruising, say, at 50 mph, and over 2k, no rattles. Only when I try to go faster.

 

The smoke smells.. sort of sweet I suppose, but like I said only for the first minute after starting, not while I'm driving.

A small coolant leak can happen pretty much anywhere.  Sweet smell that goes away after a while caused by the little build up evaporates.  Leak doesn't happen until the cooling cycle.

 

The leak could be into the intake via failing gasket, onto the block, crack in a head into the exhaust port.

I had a weird rattle like that one time.  Turned out to be a loose bolt on the alternator.

 

Look around the engine compartment for any loose bolts on anything bolted down.

Another thing it could be is the oil filler pipe lid rattling.

 

Newer cat doesn't mean it hasn't died. I don't know the age of the cat or how your weather treats exhaust systems over there but over here a new cat should see out the life of the vehicle in general.

 

Cheers

 

Bennie

condensation, Bennie should know that being a snow-bunny. The rattle - wait until something falls out or off

  • Author

Well for now at least I'm just going to chalk it up to the cold weather for how smokey it seems. We had a fairly warm morning here and there was no smoke/steam at all. The source of the rattling is still a mystery. Haven't found anything exceptionally loose or that would be clanging.

  • 2 weeks later...
  • Author

Well I found the rattle! One of my exhaust pipes lost a nut, and the other side was coming loose, so it was rattling when moving and shaking the engine. Silly fix. 

It's good to have easy fixes once in a while.

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