Evo 8 with v7 No Start After Scaling Injectors
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Evo 8 with v7 No Start After Scaling Injectors
I'm about to go insane, it seems like I'm missing something simple or the ECU is trying to play games with me...
Car has been running fine for over a month with v7 tephra mods and stock injectors. Haven't touched scaling until installing the injectors, just smoothed the maf & target af/ignition values, boost control. Installed 1200cc injectors last night, scaled them to 1200 and added proper dead time, and the car will not fire.
However, if I change the map back to the stock injector scaling, it will *sometimes* start, at will/random, but flood out with the 1200s installed of course.
Things I have checked/verified:
This happened once prior while attempting to install a buddy's set of 1200cc injectors, which we assumed to be defective (they failed the 12v tap test). When we reinstalled the stock injectors and reverted back to previous known good map, it started like nothing was wrong. When trying to revert back to the previous known good map now, it sometimes starts, sometimes doesn't (tried reverting back multiple times).
Any thoughts or ideas are appreciated, I'm about to throw the ECU in the garbage and try the AEM EMS.
Car has been running fine for over a month with v7 tephra mods and stock injectors. Haven't touched scaling until installing the injectors, just smoothed the maf & target af/ignition values, boost control. Installed 1200cc injectors last night, scaled them to 1200 and added proper dead time, and the car will not fire.
However, if I change the map back to the stock injector scaling, it will *sometimes* start, at will/random, but flood out with the 1200s installed of course.
Things I have checked/verified:
- All injectors plugged in, resitor box plugged in
- Tested injectors to 3 ohms resistance
- 12v tap shows the injectors are functional
- Verified proper immobilizer code, them attempted disabling immobilizer
- Tried different scaling values & dead times ranging from stock to appropriate for injector size
- Verified fuel pump is functional & pressure is present at the rail
This happened once prior while attempting to install a buddy's set of 1200cc injectors, which we assumed to be defective (they failed the 12v tap test). When we reinstalled the stock injectors and reverted back to previous known good map, it started like nothing was wrong. When trying to revert back to the previous known good map now, it sometimes starts, sometimes doesn't (tried reverting back multiple times).
Any thoughts or ideas are appreciated, I'm about to throw the ECU in the garbage and try the AEM EMS.
#2
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If you set your injector scaling to 1200cc for injectors that are rated at 1200cc, it's too high. The scaling you enter in ecuflash should be ~15% lower than the rated flow of the injectors. So you should be entering a scaling around 1020 to start with, which you will fine-tune after checking fuel trims.
The only tables that should be changed initially with new injectors are the injector scaling and injector latency.
The only tables that should be changed initially with new injectors are the injector scaling and injector latency.
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Originally, scaling and latency were the only changes made to the rom. I've tried several different scalings, ranging from 700-1200, but the only scaling that made the car start was the stock scaling of 513.
I've also played with the dead time (the dead time specs for these injectors was abnormally high on the manufacturer supplied paper, as high as 1.62ms at 14v), I've tried values from stock to triple the stock dead time, and the specified value by the manufacturer as well.
I will try 1020 when I get back to the shop and post my results. I'm also going to pick up a noid light to test for injector pulse.
I've also played with the dead time (the dead time specs for these injectors was abnormally high on the manufacturer supplied paper, as high as 1.62ms at 14v), I've tried values from stock to triple the stock dead time, and the specified value by the manufacturer as well.
I will try 1020 when I get back to the shop and post my results. I'm also going to pick up a noid light to test for injector pulse.
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Was able to get the car started tonight - I'm not sure what I did, but I went to the shop, turned the key, and it fired up. Doesn't run well on almost any setting.
I think the problem may be related to these cheapo injectors I'm trying out...they are Smartfire 1200cc injectors off of fleabay. Super inconsistent, it is not possible to get the car to idle stable with a variety of different settings and latencies.
The injector spec sheet calls for 1.6ms latency @ 14volts...almost double of what I have used for pte 1250s in my old Dsm. Has anyone ever seen a need for latency values this high?
Besides idle and light throttle they seem ok. But I am running pump 93, which wasn't an issue tuning on the Dsm, perhaps these cheap injectors aren't steady at low pulse width?
I think the problem may be related to these cheapo injectors I'm trying out...they are Smartfire 1200cc injectors off of fleabay. Super inconsistent, it is not possible to get the car to idle stable with a variety of different settings and latencies.
The injector spec sheet calls for 1.6ms latency @ 14volts...almost double of what I have used for pte 1250s in my old Dsm. Has anyone ever seen a need for latency values this high?
Besides idle and light throttle they seem ok. But I am running pump 93, which wasn't an issue tuning on the Dsm, perhaps these cheap injectors aren't steady at low pulse width?
#6
Was able to get the car started tonight - I'm not sure what I did, but I went to the shop, turned the key, and it fired up. Doesn't run well on almost any setting.
I think the problem may be related to these cheapo injectors I'm trying out...they are Smartfire 1200cc injectors off of fleabay. Super inconsistent, it is not possible to get the car to idle stable with a variety of different settings and latencies.
The injector spec sheet calls for 1.6ms latency @ 14volts...almost double of what I have used for pte 1250s in my old Dsm. Has anyone ever seen a need for latency values this high?
Besides idle and light throttle they seem ok. But I am running pump 93, which wasn't an issue tuning on the Dsm, perhaps these cheap injectors aren't steady at low pulse width?
I think the problem may be related to these cheapo injectors I'm trying out...they are Smartfire 1200cc injectors off of fleabay. Super inconsistent, it is not possible to get the car to idle stable with a variety of different settings and latencies.
The injector spec sheet calls for 1.6ms latency @ 14volts...almost double of what I have used for pte 1250s in my old Dsm. Has anyone ever seen a need for latency values this high?
Besides idle and light throttle they seem ok. But I am running pump 93, which wasn't an issue tuning on the Dsm, perhaps these cheap injectors aren't steady at low pulse width?
#7
Evolving Member
If that still doesn't work, look into what changed on your rom between flashes.
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#8
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#9
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The injector spec sheet calls for 1.6ms latency @ 14volts...almost double of what I have used for pte 1250s in my old Dsm. Has anyone ever seen a need for latency values this high?
Thanks in advance.
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