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Before I ask my question I need to explain a few things.
I am unable to set my ignition timing at factory settings actually I have it a little advanced for performance reasons.
The second issue is that my idle mixture screw is running lean or screwed in too far.
(this is to control excessive idle)Now my question is?
Because I have my ignition timing advanced will that, does that affect idle.( a high or low idle)
I want to know is my lean idle attributed to the advanced ignition timing or should the computer or EFI correct the idle.Hopefully I havn’t explained this to poorly.
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You’re confusing me. What kind of vehicle is this? If you have an idle mixture screw it would be carburated, but you are asking if the EFI computer is going to adjust something. What is it you are fooling wiht, because if you have EFI there is no such thing as an idle mixture screw.
You claim you cannot set the timing to stock, yet say you have intentionally advanced it thinking you will get more performance. If you can intentionally advance your timing, you can intentionally put it back to stock to.
Changing base timing, timing curves and air/fuel mixtures is what we used to tinker with to try to get more power out of cars built before 1986. With EFI, if you alter the base timing the computer is not going to like you for it and will not give you better performance but instead it will be worse. They computer also has full control over your air/fuel ratios at idle and every other speed by varying the pulsewidth if its injectors. Short of reprogramming the PCM you cannot alter it. Hence, you cannot change your idle mixture. Nor can you change your timing advance, as once again it is controlled by the PCM not by centrifugal weights or a vacuum advance mechanism. Those have gone the way of the dodo.
When asking others for help with a vehicle they do not have in front of them to see, it would help to tell those people important information such as the year, make, model and engine size of the vehicle. Also worth noting would be the mileage on the car and a detailed description of the issue you are having. If it only started after recent repairs were made, tell us that. If it only does it before it warms up or only after it warms up, that would also be needed information to help narrow down possible causes and develop a strategy to take with diagnostics.
Please help us help you.
go back to school nickwarner.
I dont want your help so rack off.to collage man,
I was learning more online last night, Someone online pointed out the difference between port and manifold vacuum and how it affects the vacuum advance. Looks like that is the information I was missing and might need, it also talks about Mechanical advance, total timing, and idle. All that stuff so I’ll be fine for a while I think.
Its a diahatsu feroza by the way.WoW…That’s a good start to getting help here. I think nickwarner asked you some legitimate questions.
I’m confused also and a little old for School. I think I’ll rack off too.
[quote=”cam” post=75343]go back to school nickwarner.
I dont want your help so rack off.[/quote]
Wow, That was unnecessarily rude. And hate to tell you Nick is correct. The screw you were adjusting is not a mixture screw, it is a air bypass screw. You can’t adjust idle because the base timing is advanced. If the computer normally advances timing by X than you adding an additional advancement (Y) means the total timing is X+Y. Once the computer realizes it can not control idle and timing it will start to retard timing and adjusting pulse-width to attempt to do the least amount of damage to the engine (pre-detonation) in the long run you will loose power and milage.
Not a good way to get started here. Nick asked very legitimate questions, and the same ones I would ask.
It sounds as though you don’t really understand what you are doing, and might be in over your head a bit, and could possibly cause harm to your vehicle. I would have asked the same questions in an attempt to figure out what you have really done there since obviously (at least to me) you can’t turn an air fuel mixture screw on a fuel injected engine.
You should rethink the way you are going about responding to those trying to help you, unless you really don’t want any help.
There was a time, back around 1980, when car computers were just coming into play, when you could find cars with both adjustment screws, manually settable timing, and tacked on idle and mixture control gadgets controlled by a central brain box.
[quote=”cam” post=75343]go back to school nickwarner.
I dont want your help so rack off.What to do in this situation? Start just turning other random screws. You may find something that works for you. Coming onto a forum where we all try to help, with attitude like yours, good luck obtaining help. Nick was right, you were wrong. Who needs to go back to school? Good luck with your repairs.
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