Its running good no missing anymore.
Ok I want to understand fuel trim today at idle the long fuel trim was at 7.8% and short fuel trim was switching between 3, 4, 5%. Should short fuel trim switch between negative and positive numbers?My car was switching between only positive numbers
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Monday, June 30th, 2014 AT 11:19 PM
JACOBANDNICKOLAS
MECHANIC
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The trims are determined by several things. Ambient temp, coolant temp, sensor readings, driving conditions, accessories being used. So, it still sounds normal to me.
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Tuesday, July 1st, 2014 AT 6:09 PM
ZEMORZEMOR
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I m curious what is the value of long term fuel trim at idle for a brand new car.
What parameters the target fuel map has. I know it has load and rpm does it has more than that?
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Wednesday, July 2nd, 2014 AT 8:53 AM
JACOBANDNICKOLAS
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Long term fuel trims should be close to zero, positive or negative single digits under normal conditions. Short term will change more quickly. They should be aprox between -5% and +5%. As you are aware, fuel trims are basically the amount of time the computer allows the injector to be open to compensate for different driving conditions. STFT therefore change often. LTFT is an average of the STFT. You mentioned that your STFT were changing only in the positive numbers. That is fine. Usually, they don't go above 8 or 9%.
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Wednesday, July 2nd, 2014 AT 7:36 PM
ZEMORZEMOR
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I ve seen the STFT of my car goes above 10 at idle for few second
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Wednesday, July 2nd, 2014 AT 8:57 PM
JACOBANDNICKOLAS
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If it's only for a couple seconds, don't worry. It's fine. When you were getting 45%, that was a concern. The computer was allowing the injector to be open for too long to compensate for the lean fuel mixture.
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Thursday, July 3rd, 2014 AT 7:55 PM
ZEMORZEMOR
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Do you know any book, eBook. Resources about fuel trim, advanced fuel trim. I want to read about it
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Friday, July 4th, 2014 AT 10:28 AM
JACOBANDNICKOLAS
MECHANIC
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Sorry, I don't. You should be able to find info on the Internet.
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Friday, July 4th, 2014 AT 9:43 PM
ZEMORZEMOR
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Can you watch this video on YouTube and tell me what can causes the stumbling
If so, if it only happens on a cold engine, it could be a few things. You could have a bad coolant temp sensor, a bad IF switch (which is the same as a IAC), weak ignition...
Keep in mind, you are dealing with two different animals with a 91 and a 96.
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Sunday, July 13th, 2014 AT 8:00 PM
ZEMORZEMOR
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My 96 accord does not long crank anymore since I replaced the fuel injectors however it intermittent stumbles not always. Sometimes it cranks two cycles and stumbles and fires up. Sometimes it cranks one cycle stumbles and fires up. Sometimes it does not stumbles at all it fires right up
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Sunday, July 13th, 2014 AT 10:35 PM
JACOBANDNICKOLAS
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Does it happen regardless if the engine is cold or warm? Have you checked compression? Have you confirmed that the fuel pressure regulator is doing its job?
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Monday, July 14th, 2014 AT 7:26 PM
ZEMORZEMOR
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Usually it stumbles after it sits for few hours. And I can hear the compression of the engine but just one compression after that it stumbles.I checked the fuel pressure regulator it good. I did not compression test