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Old 05-25-2010, 08:03 PM   #1
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Default new motor won't idle

let me preface this by saying my experience working on cars is mediocre at best...


last summer i inherited a BP from a local who had spun a bearing. He had torn the motor down, but decided a junk yard motor would be cheaper and easier than rebuilding this one.

I bought new m tuned rods, and had the short block assembled at a reputable machine shop. The rest of the assembly was done by me.

I started pulling the old 1.6 last december, and seeing as this is a hobby i took my time. I started the new motor for the first time last weekend. the first time it fired, the throttle cable was too tight, and the revs started climbing, so i shut it down. I adjusted the throttle cable and tried again. Now it will fire, the revs go up to about 1600, then sometimes the RPM will immediately slow to a stop. sometimes it will idle high for 30 seconds or so, then die. if i goose the throttle while it's dieing it will go back to a high idle for a second, then die.



any ideas?
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Old 05-25-2010, 08:20 PM   #2
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maf unplugged
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Old 05-25-2010, 08:33 PM   #3
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^^ nope, double and triple checked. nothing is unplugged as far as i can tell...
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Old 05-25-2010, 08:45 PM   #4
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flapper door on afm is closing and then shutting off fuel pump.
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Old 05-25-2010, 08:46 PM   #5
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Quote:
Originally Posted by Braineack View Post
flapper door on afm is closing and then shutting off fuel pump.
how would i check that?
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Old 05-25-2010, 08:47 PM   #6
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jump the fuel pump in the diagnostics box and see if it continues to run.
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Old 05-25-2010, 08:48 PM   #7
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Quote:
Originally Posted by Braineack View Post
jump the fuel pump in the diagnostics box and see if it continues to run.
ground to fp?

Last edited by DrewLGT; 05-25-2010 at 08:59 PM.
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Old 05-25-2010, 08:58 PM   #8
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Quote:
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flapper door on afm is closing and then shutting off fuel pump.


no dice...
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Old 05-26-2010, 07:51 AM   #9
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anybody else? i really dont know where to go from here
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Old 05-26-2010, 08:01 PM   #10
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hmmmmmm.
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Old 05-26-2010, 08:56 PM   #11
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i had a friend come by today, who is alot more experienced at spinning wrenches than i am. he also has a turbo protege...


he looked everything over and didnt see anything wrong. he had me start it up, and worked the throttle on the motor to keep it running. after it warmed up it idled pretty well. he said the idle valve is probably bad, and he has a few extra throttle bodies laying around. i'm going to swap it out and hope that fixes it.
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