Clanking, Clattering Rattle on startup
rabtrfld
09-02-2006, 08:32 PM
94 Grand Caravan 3.0L FI
Nasty clattering rattle on startup, like "metal gargling." Goes away after about two minutes. Sounds and feels like coming from intake plenum, but I think the flat top of the plenum is just acting as a sounding board. With a dowel in my teeth I can feel the clattering equally anywhere on the engine. After it goes away, if I rev the engine, the sound comes back briefly as the RPM returns to idle. The engine starts, runs, and drives just fine. Only a hint of smoke at hot idle, normal for 204,000 miles. No water leak. No engine code.
Possible clues: the noise increases or starts up again when loading the power steering, as when turning the steering wheel to the limit either way. So I removed the accessory belts (serpentine and A/C) and ran the engine, but the noise was still there on start-up and rev-down. So its not the steering pump, or the belt idler or tensioner.
When the car is put in gear, the RPM drops, but the noise does not increase. So the noise increases when the accessory end of the crankshaft is loaded, but not when the torque converter end is loaded.
I suppose one day soon I will look in the rear view mirror and see a piston rod in the road that wasn't there before.
P.S. I can get engine code 55 by flipping the key.
(Oh, that's normal... "end of codes." http://www.allpar.com/fix/80s-codes.html)
Nasty clattering rattle on startup, like "metal gargling." Goes away after about two minutes. Sounds and feels like coming from intake plenum, but I think the flat top of the plenum is just acting as a sounding board. With a dowel in my teeth I can feel the clattering equally anywhere on the engine. After it goes away, if I rev the engine, the sound comes back briefly as the RPM returns to idle. The engine starts, runs, and drives just fine. Only a hint of smoke at hot idle, normal for 204,000 miles. No water leak. No engine code.
Possible clues: the noise increases or starts up again when loading the power steering, as when turning the steering wheel to the limit either way. So I removed the accessory belts (serpentine and A/C) and ran the engine, but the noise was still there on start-up and rev-down. So its not the steering pump, or the belt idler or tensioner.
When the car is put in gear, the RPM drops, but the noise does not increase. So the noise increases when the accessory end of the crankshaft is loaded, but not when the torque converter end is loaded.
I suppose one day soon I will look in the rear view mirror and see a piston rod in the road that wasn't there before.
P.S. I can get engine code 55 by flipping the key.
(Oh, that's normal... "end of codes." http://www.allpar.com/fix/80s-codes.html)
earlyrizr
09-02-2006, 09:21 PM
maybe loose/damaged torque converter or could be broken flex plate. Did the sound just appear or did it get louder over time? when you start and shut the engine down any noise then?
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