Too much air through AAR, valve? |
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Too much air through AAR, valve? |
mtndawg |
Jan 18 2010, 11:01 AM
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#1
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Member Group: Members Posts: 414 Joined: 26-January 09 From: Granite Bay, Ca Member No.: 9,985 Region Association: None |
I've been looking for info on the AAR and most of the discussions have been about the AAR being stuck closed. I'm wondering if mine is letting too much air through at start up? I've got my 1.7L d-jet pretty close to where I want it. When it's warm I'm idling around 900ish. Vacuum lines are new and fuel pressure is perfect.
When the engine is cold and I start it up, it jumps to 2000 to 2300 rpm. When I take the hose off the AAR it's sucking a LOT of air. Restricting it with my thumb of course drops the idle. After about 3 minutes the valve is closing and the idle drops on it's own. There's also a little white smoke at start up. What do the experts think? |
ConeDodger |
Jan 18 2010, 11:04 AM
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#2
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Apex killer! Group: Members Posts: 23,852 Joined: 31-December 04 From: Tahoe Area Member No.: 3,380 Region Association: Northern California |
I am no expert but it sounds like it is doing what it is supposed to.
Are you concerned with the speed of the fast-idle? |
mtndawg |
Jan 18 2010, 11:09 AM
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#3
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Member Group: Members Posts: 414 Joined: 26-January 09 From: Granite Bay, Ca Member No.: 9,985 Region Association: None |
Shouldn't it start to idle around 1500 to 1800?
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underthetire |
Jan 18 2010, 11:14 AM
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#4
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914 Guru Group: Members Posts: 5,062 Joined: 7-October 08 From: Brentwood Member No.: 9,623 Region Association: Northern California |
Your close enough! It depends on where the mixture knob is at on the ECU, and how far your air bleed screw is at on the TB, and timing. If it's running good, leave it alone.. Your fast idle speed is fine.
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ConeDodger |
Jan 18 2010, 11:15 AM
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#5
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Apex killer! Group: Members Posts: 23,852 Joined: 31-December 04 From: Tahoe Area Member No.: 3,380 Region Association: Northern California |
Shouldn't it start to idle around 1500 to 1800? I don't know your idle spec. I can tell you this, the white smoke is not related. Wait until the idle drops and then put your finger over the hole. If the idle drops further it isn't closing completely. I suspect if your idle is wrong you need to set if but that doesn't involve the AAR. I see the Cap'n is reading this thread. HE IS AN EXPERT. If he posts, ignore mine. (IMG:style_emoticons/default/biggrin.gif) |
SLITS |
Jan 18 2010, 11:47 AM
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#6
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"This Utah shit is HARSH!" Group: Benefactors Posts: 13,602 Joined: 22-February 04 From: SoCal Mountains ... Member No.: 1,696 Region Association: None |
that's a bit high on the cold idle, but nothing critical. You might have a vacuum leak that doesn't seal until the engine is warm and metal expands.
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pbanders |
Jan 18 2010, 12:26 PM
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#7
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Senior Member Group: Members Posts: 939 Joined: 11-June 03 From: Phoenix, AZ Member No.: 805 |
I've been doing a lot of research into the AAR recently. Agree with the others, yours sounds fine. Leave it alone!
I've got an ad on WTB that's still active - anyone with an NOS 1.7/2.0 AAR that they want to sell, send me a PM. |
tod914 |
Jan 18 2010, 04:46 PM
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#8
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Advanced Member Group: Members Posts: 3,755 Joined: 19-January 03 From: Lincoln Park, NJ Member No.: 170 |
You could experiment with a plug in the airline with a center hole. That should allow less air in and give you not so high of an idle on start. Maybe a rubber stopper in the airbox port from the inside?
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