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IAC Valve - Cause for no Start?

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Old 04-08-2010, 07:43 AM
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Default IAC Valve - Cause for no Start?

Very quick question. Would a stuck (retracted in) IAC valve cause a no start?

Now on to the long story...

Many moons ago (over a year ago), the truck started to run rough at idle. Researched here on the list and a couple more places, which led me to the EGR valve. It had a bit of carbon holding it open. Cleaned it nice and area in it and throttle plates with carb. cleaner, car ran great again.

Now a few days ago, I drive for a while (half an hour). Stop for a coffee. Car won't start. Finally get it to start, seems to run fine. Drive home 15 mins. Almost home, I notice I cannot give it too much gas, because it hesitates. Have to accelerate gently. Wants to stall at idle. Get home. Let it idle in the driveway, stalls after 20 seconds.

So obviously, without my fuel pressure gauge and just basic tools because the rest are at my parents, I take out the EGR valve. It's clean. Take out the IAC valve (for the first time), quite a bit of carbon. Clean it up. Haven't put it back yet, so I can take pictures.

Main thing is...would this cause the symptoms? Also, I can't move the IAC valve plunger in or out. The spring seems to be compressed. I'm afraid it's not closing the passage and is causing it to run lean. As said, would this cause the symptoms and no start.

Thanks a bunch!

edit: Unrelated but: How do I remove/change the "new member" text below my name?
 

Last edited by pfsantos; 04-08-2010 at 09:27 AM.
  #2  
Old 04-08-2010, 12:47 PM
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As a follow up, I've read there's an adjustment procedure for the IAC, in which you push it back to a certain plunger length. What's this all about?
 
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Old 09-23-2010, 10:49 AM
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Update - was a fuel pump problem. Got a cheap one, the next year had to replace it again. Make sure to get the proper fuel pump also! Depending on your engine code (W or Z), the fuel pumps are different (pressures, etc. although they look similar).
 
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Old 09-23-2010, 12:04 PM
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It sounded like a fuel problem to me, basically the fuel pump couldn't keep up with the demand. As far as the pump AcDelco only, I found that out the hard way, also check your ground for the fuel pump as well. It grounds to under the tailgate, that seems to be a common problem also.
 
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