 Auxiliary Air Valve question |
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| torakki |
 Feb 1 2024, 07:41 PM
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Newbie  Group: Members Posts: 43 Joined: 5-October 18 From: Nor Cal Member No.: 22,545 Region Association: Northern California  |
This is on a '74 2.0. This car's been on and off the back burner for a number of years. (To many cars). It now runs very well, "Except", when it's cold, it idles perfect. As it warms, (about 2 minutes) the idle gets faster to about 1800 rpm. After a 15-to-20-minute drive, I shut it off. Restart a few minutes later and the idle is slow to wont idle fast enough to keep running. So, I'm checking the Auxiliary air valve (I took it apart) and when it's cold, it's open halfway. When it gets warm, it closes. Shouldn't it be opening when warm to let in more air to keep the idle speed up? In other words, lean out the mixture? I would think, when cold, it should be closed to richen up the fuel and warm, open to lean out.
Am I 180 degrees off? Thanks for any input. |
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| torakki |
Feb 5 2024, 08:37 PM
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Newbie Group: Members Posts: 43 Joined: 5-October 18 From: Nor Cal Member No.: 22,545 Region Association: Northern California |
QUOTE Did you read my posts? This is a known issue. It's normally just confusion on the part of the ECU. Messages from the sensors not matching reality. It happens to me (although not so badly I care) every time I run to Wegmans for something quick and then hop back in the car. It normally takes a minute or so of driving to get it happy again. Yes, I did read but confusing. So, heads cool, it runs rich, then heads warm, it runs lean. On my car, when warm, I can remove the hose from the AAV (to add more air) and idle picks up. I can use my thumb over the hose as an air valve to get the idle right. Even 20 minutes of driving wont "get it happy again". A while back, I did all the timing check, valve adjustments. Two different CHT sensors. MPS is not calibrated but is new and matches car. I believe, all original FI on board. I even had it at a shop that claims they know 914's, to get it running better. I did go through the dizzy some time back so I'm sure it's still good. I've only driven it about 50 miles in the past 5 years. I'll go through the YT video and see if I can learn more. Might be a bit since we just had a storm here in Nor Cal and blew my fence down. Thanks again for all the responses. I'll keep going on it... |
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Posts in this topic
torakki Auxiliary Air Valve question Feb 1 2024, 07:41 PM
JeffBowlsby The AAR closes when warm. When cold, it’s open. Feb 1 2024, 07:49 PM emerygt350 Yeah. Sounds like it is working. These are notorio... Feb 1 2024, 07:56 PM 914work its a designed vacuum leak, for higher idle when c... Feb 2 2024, 12:01 AM Geezer914 I second a vacuum leak. Do a smoke test, search Y... Feb 2 2024, 06:17 AM emerygt350 The aar is a controlled vacuum leak. A crummy low... Feb 2 2024, 03:33 PM torakki I am kinda leaning towards, no leaks, since I inst... Feb 2 2024, 06:14 PM emerygt350 Did you read my posts? This is a known issue. It... Feb 2 2024, 07:30 PM rjames Start with basics- setting the timing and the valv... Feb 2 2024, 08:00 PM iankarr You can see more about how the AAR works in this v... Feb 3 2024, 02:48 PM r_towle Have you removed, cleaned, and re-greased the adva... Feb 3 2024, 07:00 PM emerygt350 That dist. Plate cleaning and greasing is just a g... Feb 4 2024, 09:25 AM rjames Did it ever run correctly? If yes, what changed si... Feb 5 2024, 10:25 PM emerygt350 When you say "I remove the hose when warm... Feb 6 2024, 01:03 PM torakki [/quote]
Yes, to the intake plenum. And yes, th... Feb 8 2024, 07:32 PM StarBear Nice job! A big huzzah for getting another one... Feb 9 2024, 07:34 AM emerygt350 what a beauty.
Here is my suspicion. Your aar ... Feb 9 2024, 10:51 AM FlacaProductions One other scenario concerning the distributor - yo... Feb 9 2024, 11:51 AM
torakki
My brains getting old so I may have to print that... Feb 11 2024, 06:50 PM |
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