Bad knocking on cold start up.
Bad knocking on cold start up. I have a stock 2001 z28 a4 car with 75000 on it. I have only owned the car for about a month never had any odd sounds or problems. Anyway went out and started the car (cold here in pa), it was knocking bad let it run for about 30 seconds shut it off. opened the hood looked around and checked the oil level was good, tried to start it again same thing let it run for a couple seconds and then I shut it off.
Went inside and looked it up thought maybe it could be piston slap, went out tried it again this time the car did not crank at all (tried twice). Third time it started up ran for maybe 5 seconds and shut off by it self. Did not try aain after that. But when it did run, it had great oil pressure.
Went inside and looked it up thought maybe it could be piston slap, went out tried it again this time the car did not crank at all (tried twice). Third time it started up ran for maybe 5 seconds and shut off by it self. Did not try aain after that. But when it did run, it had great oil pressure.
I have a stock 2001 z28 a4 car with 75000 on it. I have only owned the car for about a month never had any odd sounds or problems. Anyway went out and started the car (cold here in pa), it was knocking bad let it run for about 30 seconds shut it off. opened the hood looked around and checked the oil level was good, tried to start it again same thing let it run for a couple seconds and then I shut it off.
Went inside and looked it up thought maybe it could be piston slap, went out tried it again this time the car did not crank at all (tried twice). Third time it started up ran for maybe 5 seconds and shut off by it self. Did not try aain after that. But when it did run, it had great oil pressure.
Went inside and looked it up thought maybe it could be piston slap, went out tried it again this time the car did not crank at all (tried twice). Third time it started up ran for maybe 5 seconds and shut off by it self. Did not try aain after that. But when it did run, it had great oil pressure.
Probably depends on what kind of care the previous owners took of it. Oil changes etc. Hopefully they didn't sell you the car just in time for something to happen. What weight oil is in it? It is cold this time of year and that's when you can hear piston slap much louder than usual.
I will get a video of it tomorrow, I'm going to change the oil and filter since its time and see how that looks. Im going to use m1 5w30, the previous owner used the same. He gave me all the service records since he bought the car in 2007.
Joined: Nov 2003
Posts: 6,216
Likes: 236
From: Wichita KS / Rancho San Diego
Cold weather will bring on the piston slap. My A4 has sounded terrible upon starting since it turned cold in KS. But piston slap won't cause a no-start condition or cause the car to die. I doubt you have any oil related issue.
First thing I would do is change the fuel filter, unless you know the previous owner did it recently. It's amazing how many people neglect to do that.
First thing I would do is change the fuel filter, unless you know the previous owner did it recently. It's amazing how many people neglect to do that.
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Verdad Gallardo Let it idle awhile. Your going to need to get the oil hot before changing it anyways. If the noise quiets down than you know its def. the piston slap. Maybe try 10W oil instead??
TECH Fanatic
Joined: Aug 2004
Posts: 1,373
Likes: 4
From: Auckland, Nth Is, New Zealand.
Spending time & money on changing oil etc is not going to fix an electrical issue if it won't run, but knocking could be anything, video clip!
Last edited by ls1 1990 VN; Dec 3, 2013 at 12:55 AM.
Today is cold low 30's, started it up sounds horrible and stinks really bad. The rpms do not move and don't know if you can hear the metal parts moving banging around in the video.
That's def not piston slap. Sounds like spun rod bearing? Id pull valve covers to just look and check if anything doesn't look right and keep working ur way down. Drop ur oil and run it through a magnet to see if you have alot of metal in it.
That does suck since I only have driven the car maybe 600 miles since owning it. Crazy to think the car drove fine, I parked it then the next time I try and start it has all this going on?
