Fuel Trims constantly in the negative - 2008 Honda Civic LX 1.8L Non-Vtec
- Mechanic 350
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- juergen.scholl
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Things to look at would be fuel pressure, improper air metering, evap purge solenoid.....to beginn with.
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As Jurgen suggested, what exactly are the LTFT & STFT values across the operating range of the engine?Mechanic 350 wrote: So this is my personal vehicle. Placed the scantool on it, and I'm constantly getting fuel numbers in the negative all the time. so I need some direction as to which way to go. My miles per gallon could improve a little bit. so the question is, how do I get my numbers as close to zero as possible? Because as I was studying, the #1 job of the LTFT is to keep the STFT close to zero. and that's not happening. please advise.
If we're talking +/- 10% total correction, there's probably not a whole lot to do.
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If I was going to pull a random ticket out of my bag of Honda tricks, I'd say a valve adjustment probably wouldn't be a complete waste of time.
They need to be adjusted periodically anyway, and if you've never done it, it's probably never been done.
Misadjusted valves can result in low vacuum, which will be interpreted as load by the computer resulting in more fuel than needed, and in some cases, negative fuel trim. You could see this reflected in higher than normal MAP voltage at warm low idle. If memory serves, I think 1v or less is the spec....
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Do you know how to do a screen grab on a verus? I’m still trying to learn this tool. Then I can send you the screen capture. So you see what I see.
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Also, you can save a test drive and share the
.vsm file, then anyone with Shop Stream Connect can open and view the file as if it were on their own scan tool
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There was a problem with inserting files. The problem has been fixed, now.sorry for this whatever it is in the post. if you can delete it, please. but these are the photos.
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Also, you will not find a PID for bank one sensor one oxygen sensor as it does not have one.
The wideband air fuel ratio sensor pid will be displayed in milliamps. The pid will be something like AFSENS 1
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1. engine rpm
2. Loop Status
3. Map voltage
4. Temperature Pid
any suggestion as to how I can upload the video from my Verus I took yesterday to the forum?
What I definitely noticed yesterday during the test drive, was that STFT did not drop below 800ihs to 1 volt. It never switched.
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www.scannerdanner.com/forum/off-topic-se...-a-member.html#63531
any suggestion as to how I can upload the video from my Verus I took yesterday to the forum?
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11-16-23 civic
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