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Odd idle/help?

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Old 03-31-2012, 03:28 AM
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Default Odd idle/help?

So I just replaced me header and now I have a super high idle. I usual idle right at or right below 1k rpm. It's about 2k when stopped and when I let off the gas while driving it seems to not really let off ahahah. Could this just be the computer getting used to the new header? And lack of exhaust leak now? Or maybe because I disconnected all this sensors in my intake manifold? I've also driven it about 10 miles and nothing has changed.
Old 03-31-2012, 05:04 AM
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maybee you have a vacum leak now ?
or maybee the throttlecable is out of adjustment ?
Old 03-31-2012, 07:49 AM
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computer needs to adjust
Old 03-31-2012, 12:14 PM
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Checked all vacuum lines, checked all the plugs. Everything seems to be in order and plugged in. So I'll give it a few more miles and hopefully itll knock this off. It was somewhat dangerous on the city streets hahah
Old 04-01-2012, 04:07 AM
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Originally Posted by jomps
computer needs to adjust
adjust to what ??

There is no way a craked header can cause that much troublee, so when a new one is installed, the computer sets the idle to 2000 rpm.


Try spray som starter fluid around the gasket and notice if the rpms changes.. if so, there is your leak.
Old 04-01-2012, 06:32 AM
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Sure sounds like a vacuum line is off.
Old 04-01-2012, 06:51 AM
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was there a crack on your old header, I say computer may need to adjust because the o2 sensor could get a different reading of air with new header and ecu will adjust , or could be something other going on
Old 04-01-2012, 07:20 AM
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Most likely the header is keeping the intake manifold from fully seating on the locating dowels causing a huge vacuum leak between the intake manifold and the head.
Old 04-01-2012, 01:11 PM
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Originally Posted by jomps
was there a crack on your old header, I say computer may need to adjust because the o2 sensor could get a different reading of air with new header and ecu will adjust , or could be something other going on
Well I jumped and broke my motor mounts so hard that my header broke in such a way i might as well Been running open headers.
Old 04-01-2012, 01:12 PM
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Originally Posted by cruiser54
Most likely the header is keeping the intake manifold from fully seating on the locating dowels causing a huge vacuum leak between the intake manifold and the head.

Nope intake is fully seated. That was the first thing I lined up when I put it on.
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