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idle prob... and yes, I did read the stickys

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Old 07-23-2007, 08:34 PM
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creekrat
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Default idle prob... and yes, I did read the stickys

ok, I've been fighting this idle surging for too long now. I need some help from you guys! My engine surges up and down 100-200 rpm's very quickly like in a second it goes up and down and up and down- verruy annoying! I put on my new maf and it just seemed to amplify the problem so I went back to the stock one. I have done all the idle tunes- tps set, iac clean, egr clean, base idle reset, etc. nothing seems to help. I am sort of leaning towards the computer trying to keep up with the cam but I don't know. Would a iac bypass plate help with the cam(sig) , if thats what the problem is? HELP! I'm pulling my hair out here and god knows I need to keep what I have left!
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Old 07-23-2007, 08:37 PM
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samseed101
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Default RE: idle prob... and yes, I did read the stickys

How many inches of vacuum are you pulling at idle?
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Old 07-23-2007, 08:43 PM
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creekrat
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Default RE: idle prob... and yes, I did read the stickys

last I checked was pretty low but I had a bad tb leak... let me go check quick.....

wow, that was ugly! 13 lbs and steady. on a fresh engine, looks like I have a leak somewhere
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Old 07-23-2007, 08:49 PM
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Joel5.0
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Default RE: idle prob... and yes, I did read the stickys

What Sam said + DIY KOEO/KOER/Cylinder Balance Self-Test vacuum @idle should 12"-14" Hg.

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Old 07-23-2007, 08:59 PM
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creekrat
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Default RE: idle prob... and yes, I did read the stickys

I thought vac should be up around 17-22 , slightly lower with my cam
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Old 07-23-2007, 09:03 PM
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samseed101
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Default RE: idle prob... and yes, I did read the stickys

When i put in the Steeda #19 camshaft, I went from about 16 inches of vacuum to 13.5 inches of vacuum. had to slightly increase the RPM to help steady her out.
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Old 07-23-2007, 09:08 PM
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Default RE: idle prob... and yes, I did read the stickys

I've always seen 15 - 17 on an average Mustang. I've never seen one as high as 22 without a little extra help.
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Old 07-23-2007, 09:08 PM
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Default RE: idle prob... and yes, I did read the stickys

The computer seems to be increasing my idle for me. I reset the base idle at around 850 and when I pluged the IAC back in it jumped way up to like 1100. I was trying to get it down a bit to take the pressure off the torque converter but if I lower the idle any more with the IAC disconnected the motor wants to die on me
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Old 07-23-2007, 09:09 PM
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samseed101
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Default RE: idle prob... and yes, I did read the stickys

If it's not a vacuum leak (in hte traditional sense) and if it's caused by your camshaft, then you may have to tune it out like I did.
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Old 07-23-2007, 09:11 PM
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Joel5.0
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Default RE: idle prob... and yes, I did read the stickys

ORIGINAL: creekrat

I thought vac should be up around 17-22 , slightly lower with my cam
Not with a B-303......however, you should be able to set the idle right and not have any problems.....run the KOEO/KOER self-tests and LUK the results.
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