Rich idle - 42# injectors
03-05-2009, 01:41 PM
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Rich idle - 42# injectors Ok, so I'm still trying to figure out this whole tuning thing...
I just installed 42# injectors in my car and changed the IFR table using redsupra's injector excel spreadsheet.
The car has a very rich idle, around 10.5. Tune is stock other than some basic codes turned off, IFR changed, etc. After searching around here for awhile, I've seen some people talk about altering the VE table from 400-1200rpms. That did not help.
I have no idea where to start to correct this
Yes, I've read stuff about offset tables and pulsewidths, etc.... I was under the impression that since they are stock injectors, they would be the same... I guess I was wrong.
I just installed 42# injectors in my car and changed the IFR table using redsupra's injector excel spreadsheet.
The car has a very rich idle, around 10.5. Tune is stock other than some basic codes turned off, IFR changed, etc. After searching around here for awhile, I've seen some people talk about altering the VE table from 400-1200rpms. That did not help.
I have no idea where to start to correct this
Yes, I've read stuff about offset tables and pulsewidths, etc.... I was under the impression that since they are stock injectors, they would be the same... I guess I was wrong.
03-05-2009, 02:05 PM
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I used RedSupra's excel sizer. The flow sheet said they were 42.6 @ 3bar.
49.17030 49.48033 49.79036 50.10038 50.41041 50.72044 51.03047 51.27849 51.58851 51.89854 52.14656 52.45659 52.76662 53.01464 53.32467 53.63469 53.88272
03-05-2009, 02:17 PM
#4
Ahh... They may be the same design as OEM units (or similar anyway) but that doesn't mean that their flow characteristics are the same. There is more to tweak other than just the IFR to get things back in line. Your IFR is slightly higher than the canned value I use by less than 1% at the bottom and about 4.5% up top but if you arrived at values based on flow numbers included with the injectors, then that is the way to go. There still isn't enough info here to help too much with. You say 10.5 at idle; that is clearly in OL, so is that right at startup, just after, or does it just fail to go into CL? What is the IPW at the times when the car idles it's most lean? What is the commanded AFR at the time you get 10s? I am away from my backup, so posting your file is still relevant for both myself and anyone else looking into it for ya.
-Steve
-Steve
03-05-2009, 04:15 PM
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You say 10.5 at idle; that is clearly in OL, so is that right at startup, just after, or does it just fail to go into CL? What is the IPW at the times when the car idles it's most lean? What is the commanded AFR at the time you get 10s? I am away from my backup, so posting your file is still relevant for both myself and anyone else looking into it for ya.
-Steve
-Steve
For about 30 seconds after startup, it idles slightly ok then starts getting worse and worse til it wants to stall out.
Sorry, I am a newbie...guess I got in too deep with this... I don't know the different between open loop or closed loop, and I don't know how to tell when it switches.
