New Stumpers ? ? ?
off topic
not much resolution on those injectors? i.e too big for your goals?
on topic
sure i read e85 have miss issues at richer conditions maybe you need to be at 13's (they swear by leaning out)
calibrated your wideband recently?
not much resolution on those injectors? i.e too big for your goals?
on topic
sure i read e85 have miss issues at richer conditions maybe you need to be at 13's (they swear by leaning out)
calibrated your wideband recently?
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The Zeitronix does not have the need for a calibration.
It looks like Mr. Buschur hit the nail on the head with the SURGING. The E85 is so much more efficient that the turbo is spooling too fast that it surges at low rpm. Upon changing the duty cycle on my AVC-R, the condition has diminished substantially. It still happens, but no where near as severe.
I believe that the rest of the issue is the result of the fuel table not being accepted for values over 100 load. I am going to try a fresh rom and start the tune all over again. It seems that for some odd reason after modding a rom so many times, that something becomes corrupt and the tune goes to hell. A fresh flash usually cures this.
Please keep the suggestions coming. All is appreciated.
If it was the fuel pump, wouldn't I have issues at the top end WOT when my injector duty cycles are much higher? I may pull it and mod it (press in the relief ball) to see if it makes an improvement. FWIW I do have an AMS fuel rail too.
Plugs are NGK BPR 8 EIX. Iridium. They have less than 1k miles on them.

Plugs are NGK BPR 8 EIX. Iridium. They have less than 1k miles on them.

I'm not sure how things would work with such large injectors and a small fuel pump.
If you can get a fuel pressure gauge on it and watch it somehow that would be something to try or swap a good known FP.
Hell that might not even be the issue, it could have something to do with the rom, try that and if it doesn't help I would look at the fuel pump as the issue.
Paul, this happened to me today when I was tuning the 2000s... Check your logs and see if one of the load numbers is out of whack... I had to change my 1byte load factor as it was giving me incorrect information...
Did you try lowering your injector scaling on E85 and see if the AFR becomes richer? Try working backwards, ie, lower the injector scaling on e85 until you get the richer AFR you want. Then play with the latency to get the fuel trims in line. Ofcourse that will screw up your 91 octane trims, but it is worth a try simply to get the E85 tune working.
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Fuel lean issue : Could the relay for the 9-12 v fuel pump cross over go bad?
This could be 2 fold as the cross over point could be around the 3000rpm region.
Is there a possibility we can get some code for the ECU fuel pump switching point? ? ? I have suspicion that it is around 2900 to 3000 rpm.
This could be 2 fold as the cross over point could be around the 3000rpm region.
Is there a possibility we can get some code for the ECU fuel pump switching point? ? ? I have suspicion that it is around 2900 to 3000 rpm.
Have you tried rescaling the MAF CAL table to see over 1600HZ (scaling side) and then upping it on the other side? This should raise the IDC's a quite a bit when seeing a lot of boost at your high HZ levels. First, up the number to see if AFR's lower and then adjust MAF RAW for fine tuning at those HZ levels.
I don't know if this is a band-aid for the actual issue or is necessary when running at your power level.
Also, verify the FPR vacume is not leaking at those levels. (but your IDC's aren't moving that much up there so that probably isn't the issue)
Good Luck man!
EDIT: as you know, this will throw off your pump gas fuel map also.
I don't know if this is a band-aid for the actual issue or is necessary when running at your power level.
Also, verify the FPR vacume is not leaking at those levels. (but your IDC's aren't moving that much up there so that probably isn't the issue)
Good Luck man!
EDIT: as you know, this will throw off your pump gas fuel map also.
Last edited by evoredy; Aug 21, 2010 at 11:59 AM.
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I would rather not mess with the MAF as it tends to create issues elsewhere.
I did find a little discrepancy though....
The "Accel Enrichment (Incorrect)" table has potential issues. Upon comparing it to a stock rom(s) vs v7 the scaling for the RPM is different. The area that the problem I am having occurs where the difference is. I am curious as to if making changes will affect the cut out I get at low rpm.
I did find a little discrepancy though....
The "Accel Enrichment (Incorrect)" table has potential issues. Upon comparing it to a stock rom(s) vs v7 the scaling for the RPM is different. The area that the problem I am having occurs where the difference is. I am curious as to if making changes will affect the cut out I get at low rpm.
Last edited by Appauldd; Aug 23, 2010 at 10:42 PM.
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Tried the bypass on the Fuel Pump relay....It did nothing to resolve the issues at all.
This makes me believe that there is something in the program this is causing the cutout below 3500 and the AFR not wanting to go any richer.
GRRRR.......please offer some more suggestions.
This makes me believe that there is something in the program this is causing the cutout below 3500 and the AFR not wanting to go any richer.
GRRRR.......please offer some more suggestions.
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Problem 1 - Replace your Walbro.
Problem 2 - Surging, per DB, is likely it. Mine does the same thing. It mostly happens when I'm doing "tuning" runs where I go WOT at 2300 rpm. If I go WOT at 3000 rpm, its hardly there. Its worse though during lean spool up conditions. If I left AFRs drift higher than 12.5:1, then I'll get progressively more hesitation on spool. Leaner conditions are likely allowing spark blow out or lack of ignition.
Problem 2 - Surging, per DB, is likely it. Mine does the same thing. It mostly happens when I'm doing "tuning" runs where I go WOT at 2300 rpm. If I go WOT at 3000 rpm, its hardly there. Its worse though during lean spool up conditions. If I left AFRs drift higher than 12.5:1, then I'll get progressively more hesitation on spool. Leaner conditions are likely allowing spark blow out or lack of ignition.
Last edited by mrfred; Aug 25, 2010 at 08:11 AM.
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I am starting to play with the injector scaling. Possibly the scaling would allow for more fuel. Maybe these low impedance 1450cc injectors are just too slow because of their size to accurately run well at low rpm levels.
Could be a voltage issues too. I have a mini battery that never shows over 13.8v. The car starts and runs well (except for the problem areas). I may have to go to a full size battery and locate it in the trunk. This should stabilize the voltage and hopefully cure the issues.
Could be a voltage issues too. I have a mini battery that never shows over 13.8v. The car starts and runs well (except for the problem areas). I may have to go to a full size battery and locate it in the trunk. This should stabilize the voltage and hopefully cure the issues.
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The BlueMax injectors are slower than the factory injectors, but they are faster than all the top end high-Z injectors (ID1000, FIC1100, ID2000, FIC2150...)
Last edited by mrfred; Aug 25, 2010 at 08:26 AM.





