Open VS closed loop.
Thread Starter
Intermediate
Joined: Sep 2002
Posts: 43
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From: Kyrkhult Blekinge
Open VS closed loop.
Hello gurus!!
My car seems to go in open loop untill 130degr and the goes to closed loop and it stays there no matter what happends,,any suggestions ?? :confused:
My car seems to go in open loop untill 130degr and the goes to closed loop and it stays there no matter what happends,,any suggestions ?? :confused:
Thread Starter
Intermediate
Joined: Sep 2002
Posts: 43
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From: Kyrkhult Blekinge
Re: Open VS closed loop. (Aaron71771)
I have datamaster hooked up and what i could see it is never going into other modes. I`am just a beginner to this.. :crazy:
[Modified by Swede, 1:28 PM 7/3/2003]
[Modified by Swede, 1:28 PM 7/3/2003]
Le Mans Master
Joined: Feb 2002
Posts: 7,858
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Re: Open VS closed loop. (Swede)
That sounds normal for an '87 (L98). Once it goes into closed loop it should stay there unless you go WOT (Wide Open Throttle) then it should look to the WOT air/fuel tables for what air/fuel ratio to use instead of looking at the oxygen sensors for what air/fuel mixture to use. In closed loop under part-throttle (reading the oxygen sensors output) it should try to set 14.7:1 air/fuel mixture, that is the goal. That mixture is not best for WOT throttle because it will cook the valves from too much heat due to the air (oxygen) content at that mixture ratio. It has been said that the leanest the WOT mixture should be is 12.7:1 and no more.
Summary: I think what you are observing is nc (Normal Condition).
Summary: I think what you are observing is nc (Normal Condition).
Former Vendor
Joined: Jun 2001
Posts: 7,204
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From: St Marys PA
Re: Open VS closed loop. (Lone Ranger)
That is fine. There are several parameters that need to be met before the car will go to closed loop. A few off the top of my head are.
1. O2 sensor must reach ~600*
2. The coolant must reach preset temp
3. The timers in the ECM must time out.
Also during WOT the open closed loop will remain in the closed position even at WOT. However the learn control will shut off during the run. And the BLM will lock on 128.
Your fine and have nothing to worry about. :cheers:
1. O2 sensor must reach ~600*
2. The coolant must reach preset temp
3. The timers in the ECM must time out.
Also during WOT the open closed loop will remain in the closed position even at WOT. However the learn control will shut off during the run. And the BLM will lock on 128.
Your fine and have nothing to worry about. :cheers:
Thread Starter
Intermediate
Joined: Sep 2002
Posts: 43
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From: Kyrkhult Blekinge
Re: Open VS closed loop. (ski_dwn_it)
Thanks!!
You are absolutly right both,,Thats me who is not understanding. When I hit the throttle I see when it changes from 14,73 to 12 and even go down to 11,23 for a while. Just another ques,,My AFGS gm/sec is not reaching ower 204,,I have some old results when I have been up to 233,,Is this something that is wrong ??? :confused:
[Modified by Swede, 3:47 PM 7/3/2003]
You are absolutly right both,,Thats me who is not understanding. When I hit the throttle I see when it changes from 14,73 to 12 and even go down to 11,23 for a while. Just another ques,,My AFGS gm/sec is not reaching ower 204,,I have some old results when I have been up to 233,,Is this something that is wrong ??? :confused:
[Modified by Swede, 3:47 PM 7/3/2003]
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Joined: Sep 2001
Posts: 62,160
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From: Athens AL
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Re: Open VS closed loop. (ski_dwn_it)
That is fine. There are several parameters that need to be met before the car will go to closed loop. A few off the top of my head are.
1. O2 sensor must reach ~600*
2. The coolant must reach preset temp
3. The timers in the ECM must time out.
Also during WOT the open closed loop will remain in the closed position even at WOT. However the learn control will shut off during the run. And the BLM will lock on 128.
1. O2 sensor must reach ~600*
2. The coolant must reach preset temp
3. The timers in the ECM must time out.
Also during WOT the open closed loop will remain in the closed position even at WOT. However the learn control will shut off during the run. And the BLM will lock on 128.
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From: Athens AL
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Re: Open VS closed loop. (scorp508)
So if i just start the car, it would be like 5-10 sec and those timers would time out?
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From: Boston, MA
Re: Open VS closed loop. (vader86)
So if i just start the car, it would be like 5-10 sec and those timers would time out?
