PCM Diagnostics & Tuning HP Tuners | Holley | Diablo

Cant get my injector pulsewidth below 3.0 ms

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Old May 1, 2005 | 01:40 PM
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Default Cant get my injector pulsewidth below 3.0 ms

at idle. I think this may be causing a lot of my issues with my idle misture being really rich. The ve table no matter how much i fool with it doesnt seem to drop the PW
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Old May 1, 2005 | 04:31 PM
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Originally Posted by HumpinSS
at idle. I think this may be causing a lot of my issues with my idle misture being really rich. The ve table no matter how much i fool with it doesnt seem to drop the PW
My idle mixture is not rich, and my mixture only goes below 3 sometimes when I am in decel (not DFCO), at idle I am always a little over 3 at 900 rpms.
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Old May 1, 2005 | 04:53 PM
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maybe i need to raise my idle
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Old May 1, 2005 | 05:39 PM
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Let me correct myself, I am seeing 2.8-2.9ms at idle. 3.0 doesn't sound like too far of a stretch. What size injector are you using?
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Old May 1, 2005 | 05:42 PM
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32 lbs/hour racetronox
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Old May 1, 2005 | 06:01 PM
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I am having the same issue. Stock 28's here.
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Old May 1, 2005 | 09:07 PM
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I noticed that my pulsewidths at idle were a lot jumpier, and a little more rich, with proportional idle disabled and in speed density mode. You may want to try enabling proportional idle, IF all your other fueling is right. DO you have it disabled?

Also, here is a good link for you. It might help you out.
http://www.diy-efi.org/gmecm/papers/747fuel.txt
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Old May 1, 2005 | 09:15 PM
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both of us are open loop SD
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Old May 1, 2005 | 10:13 PM
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Originally Posted by HumpinSS
both of us are open loop SD
What he said.
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Old May 1, 2005 | 10:17 PM
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Aha. Open loop. Did it at least eliminate any bucking and surging? I don't know what you can do about your idle AF ratio is you are running open loop.
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Old May 1, 2005 | 10:21 PM
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This is what I have found out. I got my VE table all dialed in to 13.0 like I wanted, but when I switched back to the stock ol afr table, my afr is still all out of wack. I have tried lowering the ve to get me to the desired 14.7 that I want (still OL), but it doesn't seem to want to go lower then 14.0.
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Old May 1, 2005 | 10:22 PM
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Here is a link to my older post concering this.

https://ls1tech.com/forums/pcm-diagnostics-tuning/308517-afr-changes-open-loop-multiplier-table.html

Not trying to hi-jack the thread Humpin....
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Old May 2, 2005 | 09:02 AM
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racetronix injectors are weird, ws6firebirdta00 been playing with these suckers for weeks now and can't get them quite right. proportional fueling, minimal pulse width tables, no matter what you do they can't seem to get in line.
on the other hand, i just put in my cheapo used svo30's in, calibrated IFR, and they fired up and idled perfect. my max duty cycle went down from 96% to 75%, and with ZERO other tweaks my VE table is dead on between -2 and 0 (except deceleration cells, i still gotta look into these). these seem to work flawless for some reason.
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Old May 2, 2005 | 09:16 AM
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Black02SS has the stockers so i doubt its the injectors
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Old May 2, 2005 | 04:24 PM
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Originally Posted by HumpinSS
Black02SS has the stockers so i doubt its the injectors
Sounds suspiciously like there are issues with flow rate vs. kpa. Have you tinkered with that?
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Old May 2, 2005 | 04:25 PM
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No not yet because i refuse to be an "IFR tweaker"
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Old May 2, 2005 | 05:26 PM
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Originally Posted by HumpinSS
No not yet because i refuse to be an "IFR tweaker"
Did you put your IFR table in the same straight across? You should probably find a scaled one to work off of. I can't imagine what a straight-across IFR table would do to my trims.
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Old May 2, 2005 | 05:31 PM
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I don't think his IFR is straight. I do believe it is scaled from smaller to larger according to vacuum. I had several of his files and can't seem to locate a single one.

So whats my deal then?? LOL
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Old May 2, 2005 | 05:33 PM
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Here is a question as I have never been a "IFR tweaker" myself and it is probably common sense as I have had a rough day. Which value on the IFR table corresponds to idle, is it 0vac or 80vac?
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Old May 2, 2005 | 05:44 PM
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For the third time 0 vac
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