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Huge bump=P0300 code

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Old Oct 15, 2014 | 08:49 AM
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Default Huge bump=P0300 code

They stripped the road surface under an overpass and I couldn't see the bump sign at night when it was raining. Since I'm slammed, it didn't feel very good when I hit the much higher surface at 55mph. I didn't get any codes until I stopped at a light and then it all began, code P0300 popped up and the car idled really rough. At speed the check engine light flashes and that's not good so I drove the car straight home. I have a 97 A4, thanks for the help.
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Old Oct 15, 2014 | 12:12 PM
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Originally Posted by mfastert
They stripped the road surface under an overpass and I couldn't see the bump sign at night when it was raining. Since I'm slammed, it didn't feel very good when I hit the much higher surface at 55mph. I didn't get any codes until I stopped at a light and then it all began, code P0300 popped up and the car idled really rough. At speed the check engine light flashes and that's not good so I drove the car straight home. I have a 97 A4, thanks for the help.
I know the feeling all too well brother, kills me hitting bumps on the hwy. Check the simple stuff first: sounds like a plug wire or two maybe came loose. Maybe a loose coil pack connection or bad coil pack. Could also be a broken valve spring.
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Old Oct 15, 2014 | 12:34 PM
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Originally Posted by Dcollins3208
Check the simple stuff first: sounds like a plug wire or two maybe came loose. Maybe a loose coil pack connection or bad coil pack.
My guess is it's one of these. I'd also check the battery connections.
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Old Oct 16, 2014 | 11:38 AM
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It was the plug wire on the spark plug end! The rubber hose was hanging and not attached. It looks like the spring on the inside is green and corroded, assuming it's a copper spring.

Will this problem keep getting worse or am I ok here and should just aviod huge bumps in the road?
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Old Oct 16, 2014 | 11:43 AM
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Obviously avoid huge bumps! New plug wires are cheap enough
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Old Oct 16, 2014 | 12:05 PM
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Originally Posted by mfastert
It was the plug wire on the spark plug end! The rubber hose was hanging and not attached. It looks like the spring on the inside is green and corroded, assuming it's a copper spring.

Will this problem keep getting worse or am I ok here and should just aviod huge bumps in the road?
If one plug wire is bad more could be. I'd replace the whole set.
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Old Oct 16, 2014 | 01:11 PM
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Originally Posted by Corvette_Ed
If one plug wire is bad more could be. I'd replace the whole set.
That's what I told him in over in the General Section !
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Old Oct 16, 2014 | 04:02 PM
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Purchase a set of GM Performance RED wires. While you have the wires OFF, its a good opportunity to replace the plugs with some GM Irridum plugs if you have not done so in the last 50-60 K miles.

GM Performance Wires:







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