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99 head swap backfires won't start

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Old 08-26-2011 | 11:27 AM
  #21  
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You'll be a pro next time.

http://www.miata.net/garage/timingbelt.html
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Old 08-26-2011 | 11:30 AM
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Since you probably had the cam gears off, Make sure that the pin in the exhaust points to E and the pin in the Intake points to I.

When everything lines up, your first cam lobes should point outward, also.
Old 08-26-2011 | 11:31 AM
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that link describes it better.
Old 08-26-2011 | 11:42 AM
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Originally Posted by olderguy
Since you probably had the cam gears off, Make sure that the pin in the exhaust points to E and the pin in the Intake points to I.

When everything lines up, your first cam lobes should point outward, also.
I just point the pins to 12 O'clock, far less confusing.
Old 08-26-2011 | 02:38 PM
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Update: the car now starts.

But will only idle with the throttle cracked, Vacuum is low around 5 in hg, and its running around 10 A/F normally 12A/F at idle. the IAC is sucking what seems like a lot of air. If I plug the IAC and start it with the throttle cracked it pulls almost 10 in hg.

I will let the car cool down then try cam timing again? any other thoughts?
Old 08-26-2011 | 03:29 PM
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More pictures just in case, please.

I loved "We doubt because we care", hahaha!
Old 08-26-2011 | 04:11 PM
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okay I will tear into it again and send more pics
Old 08-26-2011 | 04:25 PM
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it's pretty easy. here's how the cam lobes are supposed to be on the first cylinder closest to the timing belt.
Attached Thumbnails 99 head swap backfires won't start-cams.jpg  
Old 08-26-2011 | 06:50 PM
  #29  
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correct cam timing

New plug, ran about 30 minutes
Attached Thumbnails 99 head swap backfires won't start-018.jpg   99 head swap backfires won't start-013.jpg  
Old 08-26-2011 | 06:55 PM
  #30  
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The car is running rich, has a low idle around 500R RPM, and has low vacuum around 5 In Hg. Any pointers?
Old 08-26-2011 | 07:18 PM
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Could be a tooth off?
Old 08-26-2011 | 08:10 PM
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Bent valve? lol j/k.
Old 08-26-2011 | 08:43 PM
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playing with the cam sensor position brought the idle way up and also brought the vacuum up to about 17 in Hg. Still quite not right but I will mess with it more on Sunday.
Old 08-26-2011 | 09:15 PM
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lol @ "we doubt because we care"

Compression test to rule out the obvious, then reset your base timing.
Old 08-27-2011 | 05:16 AM
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I dont know if that mark on the wheel is just a scratch or an indicator mark but are you sure the cam is lined up correctly?
Old 08-28-2011 | 11:51 PM
  #36  
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Reset MS and did base timing it runs pretty well now just need to iron out a few things with the tune and all should be good. Thanks again for everyone's help!
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