Had this problem since my rebuild with medium porting and retune.

Any time , any gear, at about 40-60% throttle at 4500 -5500 rpm massive hesitation. AFR's are in check at about 11.4 at this point and boost will be about 10psi. What could be the cause? At WOT no hesitation at all. Is i lean it a little it gets better, but I afraid to lean ir too much.

Anyone had this problem?

 

injector staging? also your wideband gauge may not read fast enough to tell you if there is a super rich or super lean spot. a lot of widebands have a pretty slow sample rate and a choppy display (AEM for example, also the cheaper Innovate gauges).

 

How exactly would staging cause hesitation at part throttle, and not full throttle?

Im not exactly a professional tuner, now learning.

 

it's really hard to make a diagnosis without a datalogit log of rpm, boost, and AFR (through wideband analog input). The fuel map could be rich enough in the boost areas that, while the car does go leaner during staging, it's not lean enough to feel. Again it's hard to say based on you glancing at a wideband display which probably has a low sample rate

or it could be something completely unrelated. hard to say. What injectors do you have, what's your overall setup?

 

What is your injector set-up? It is usually caused by the opening of larger secondary injectors creating a "rich" spot in that point of transition. Hence the stumble effect. Although sometimes it can hard to "smooth out " the injector stage in a tune a good tuner is capable of working it out on the street. Leaner afr's are needed at varoius cruise rpm load points.

 

Sounds like a problem with the tune. Many tuners focus mainly on full throttle and forget that sometimes you will be in boost at part throttle.

 

agreed. Tune is bad in that area

 

Actually I did do a data log, which has a afr at 11.4 during the hesitation.

Setup:

13b REW w/medium street port
GT4094r single
1000/1600 inj staged

 

1000cc pri/1600cc sec staged injectors.......and thats exactly what it seems like "stumble effect" However what I notice if I do a WOT pull there is no hesitation.

This hesitation seems to be at the injector stage transition point.

Im tuned it my self from scratch (did well so far) except this little prob I am trying to overcome.

If it is infact staging related, please give me some advise about what I need to do with the tune map at the point of staging. should I lower the stage amount and add fuel to the cells above the stage point?

 

i can't see your log so I don't know if you even have a good enough sample rate to properly diagnose anything. if you are only getting 5 samples per second you could easily miss a problem.

Take a screenshot (hit print screen and paste into MS paint) of the settings 5 tab in your map and post it up, or post the whole map.

Also post a .txt log file. In the monitor window, log only Advance and Aux. Turn everything else off to maximize sample rate. Do some part throttle boosting with the hesitation, and then do some WOT boosting.

What injector resistors are you using? Or do you have an FJO injector driver?

 

Here's my log with part throttle hesitation (copy and pasted from excel) hesitation occurs from about reading 239 - 263.

Also how does injector resistor come into the picture? My injectors are low imp and i dont use resistors since my ems allows you to set the imp. inthe ecu setup and does not require any resistor. Strange enough, it was after I switched from hihh to low imp.injectors that the problem started. Should i still be using resistors?



READING LogTime RPM Pressure FR1 IgnTiming TPS InjMS BatVolts
0 00:00:00 2,123 -7.397 14.400 23.800 11.500 1.872 13.800
1 00:00:00 2,108 -7.760 14.900 23.800 7.800 1.812 13.800
2 00:00:00 2,110 -8.412 14.800 23.800 5.600 1.702 13.700
3 00:00:00 2,105 -8.992 14.600 23.800 2.800 1.650 13.800
4 00:00:00 2,039 -9.645 14.400 23.400 1.000 1.632 13.700
5 00:00:00 2,082 -10.225 13.500 23.600 0.000 1.590 13.800
6 00:00:00 2,134 -10.588 12.900 23.800 0.000 1.550 13.700
7 00:00:00 2,044 -10.733 13.300 23.400 0.000 1.542 13.700
8 00:00:00 2,087 -10.805 14.800 23.600 0.000 1.508 13.800
9 00:00:00 2,069 -10.878 14.700 23.600 0.000 1.504 13.700
10 00:00:00 2,060 -10.805 16.000 23.600 0.000 1.506 13.700
11 00:00:00 2,054 -10.878 16.300 23.600 0.000 1.504 13.800
12 00:00:00 2,038 -10.878 16.000 23.400 0.000 1.504 13.700
13 00:00:01 2,046 -10.878 17.100 23.400 0.000 1.504 13.700
14 00:00:01 2,032 -10.878 16.700 23.400 0.000 1.502 13.700
15 00:00:01 2,022 -10.805 16.400 23.400 0.000 1.504 13.700
16 00:00:01 2,012 -10.805 15.700 23.400 0.000 1.502 13.700
17 00:00:01 2,000 -10.805 15.500 23.400 0.000 1.502 13.700
18 00:00:01 2,001 -10.733 15.300 23.400 0.000 1.540 13.700
19 00:00:01 2,002 -10.370 15.800 23.400 0.000 1.582 13.700
20 00:00:01 1,968 -10.298 15.700 23.000 0.000 1.582 13.700
21 00:00:01 1,987 -10.225 15.700 23.200 0.000 1.584 13.700
22 00:00:01 1,980 -10.225 15.200 23.200 0.000 1.584 13.700
23 00:00:01 1,946 -10.225 14.400 22.800 0.000 1.584 13.700
24 00:00:01 1,972 -10.153 13.700 23.000 0.000 1.622 13.700
25 00:00:02 1,929 -10.153 13.400 22.800 0.000 1.622 13.700
26 00:00:02 1,939 -10.153 13.500 22.800 0.000 1.622 13.700
27 00:00:02 1,914 -10.153 13.800 22.600 0.000 1.622 13.700
28 00:00:02 1,911 -10.153 14.400 22.600 0.000 1.622 13.700
29 00:00:02 1,872 -10.153 13.800 22.200 0.000 1.622 13.700
30 00:00:02 1,887 -10.080 14.400 22.400 0.000 1.622 13.700
31 00:00:02 1,840 -10.008 13.800 22.000 0.000 1.624 13.700
32 00:00:02 1,836 -10.008 13.100 22.000 0.000 1.624 13.700
33 00:00:02 1,819 -9.935 13.400 21.800 0.000 1.624 13.700
34 00:00:02 1,772 -9.863 14.100 21.400 0.000 1.626 13.700
35 00:00:02 1,789 -9.790 14.100 21.600 0.000 1.626 13.600
36 00:00:02 1,733 -9.790 14.500 21.200 0.000 1.626 13.700
37 00:00:03 1,702 -9.718 13.100 20.800 0.000 1.626 13.700
38 00:00:03 1,707 -9.718 13.000 20.800 0.000 1.626 13.600
39 00:00:03 1,620 -9.863 13.500 20.200 0.000 1.624 13.600
40 00:00:03 1,606 -9.935 13.500 20.200 0.000 1.622 13.600
41 00:00:03 1,597 -9.573 13.700 20.000 0.000 1.624 13.600
42 00:00:03 1,551 -9.355 13.800 19.600 0.000 1.624 13.600
43 00:00:03 1,462 -9.427 14.000 19.200 0.000 1.622 13.600
44 00:00:03 1,370 -9.282 14.200 18.800 0.000 1.622 13.600
45 00:00:03 1,358 -8.992 14.000 18.800 0.000 1.622 13.600
46 00:00:03 1,350 -8.992 13.600 18.600 0.000 1.622 13.500
47 00:00:03 1,296 -8.992 12.800 18.400 0.000 1.622 13.500
48 00:00:03 1,250 -8.847 13.100 18.400 0.000 1.688 13.500
49 00:00:04 1,244 -8.702 12.000 18.200 0.000 1.688 13.500
50 00:00:04 1,209 -8.485 11.800 18.200 0.000 1.694 13.500
51 00:00:04 1,164 -8.267 13.200 18.000 0.000 1.744 13.500
52 00:00:04 1,152 -8.195 12.700 18.000 0.000 1.748 13.500
53 00:00:04 1,139 -7.905 12.300 18.000 0.000 1.798 13.500
54 00:00:04 1,101 -7.832 12.600 17.800 0.000 1.842 13.500
55 00:00:04 1,054 -7.687 12.100 17.800 0.000 1.848 13.500
56 00:00:04 1,024 -7.397 12.600 17.600 0.000 1.896 13.500
57 00:00:04 1,011 -7.107 12.500 17.600 0.000 1.942 13.400
58 00:00:04 1,008 -6.962 12.100 17.600 0.000 1.984 13.500
59 00:00:04 987 -6.817 12.700 17.400 0.000 1.988 13.500
60 00:00:04 970 -6.599 12.800 17.400 0.000 2.032 13.500
61 00:00:05 957 -6.454 12.500 17.400 0.000 2.036 13.500
62 00:00:05 951 -6.309 12.300 17.400 0.000 2.078 13.600
63 00:00:05 958 -6.237 12.000 17.400 0.000 2.080 13.500
64 00:00:05 966 -6.237 12.300 17.400 0.000 2.080 13.500
65 00:00:05 984 -6.309 12.400 17.400 0.000 2.078 13.500
66 00:00:05 998 -6.382 12.600 17.400 0.000 2.078 13.500
67 00:00:05 1,000 -6.454 12.700 17.600 0.000 2.036 13.500
68 00:00:05 1,009 -6.527 12.800 17.600 0.000 2.034 13.500
69 00:00:05 1,016 -6.527 12.300 17.600 0.000 2.034 13.500
70 00:00:05 1,023 -6.599 11.800 17.600 0.000 2.030 13.500
71 00:00:05 1,023 -6.599 12.500 17.600 0.000 2.030 13.500
72 00:00:05 1,034 -6.672 12.400 17.600 0.000 2.030 13.500
73 00:00:05 1,047 -6.744 12.100 17.600 0.000 1.988 13.500
74 00:00:06 1,065 -6.817 12.800 17.800 0.000 1.986 13.500
75 00:00:06 1,080 -6.962 12.300 17.800 0.000 1.982 13.500
76 00:00:06 1,091 -7.034 12.600 17.800 0.000 1.942 13.500
77 00:00:06 1,089 -7.179 12.600 17.800 0.000 1.940 13.500
78 00:00:06 1,094 -7.179 12.100 17.800 0.000 1.940 13.500
79 00:00:06 1,096 -7.179 11.800 17.800 0.000 1.940 13.500
80 00:00:06 1,091 -7.252 12.100 17.800 0.000 1.940 13.500
81 00:00:06 1,067 -7.324 11.900 17.800 0.000 1.898 13.500
82 00:00:06 1,057 -7.252 12.300 17.800 0.000 1.940 13.500
83 00:00:06 1,065 -7.107 12.600 17.800 0.000 1.942 13.500
84 00:00:06 1,073 -7.107 12.200 17.800 0.000 1.940 13.500
85 00:00:06 1,070 -7.179 12.700 17.800 0.000 1.940 13.500
86 00:00:07 1,064 -7.179 12.400 17.800 0.000 1.940 13.600
87 00:00:07 1,071 -7.179 12.500 17.800 0.000 1.940 13.500
88 00:00:07 1,080 -7.179 12.300 17.800 0.000 1.940 13.500
89 00:00:07 1,081 -7.252 12.500 17.800 0.000 1.940 13.600
90 00:00:07 1,077 -7.252 11.800 17.800 0.000 1.940 13.500
91 00:00:07 1,076 -7.252 12.400 17.800 0.500 1.940 13.500
92 00:00:07 1,067 -2.901 12.500 17.800 23.400 2.972 13.400
93 00:00:07 1,074 -1.015 13.500 17.800 22.200 3.752 13.500
94 00:00:07 1,129 -1.813 12.000 18.000 1.400 3.338 13.400
95 00:00:07 1,159 -3.046 12.400 18.200 5.300 4.184 13.600
96 00:00:07 1,210 -3.916 13.300 18.400 18.200 5.556 13.500
97 00:00:07 1,172 -2.828 15.100 18.200 20.900 3.666 13.500
98 00:00:08 1,128 -1.958 14.600 18.000 21.100 4.056 13.500
99 00:00:08 1,107 -1.740 12.500 18.000 21.500 4.184 13.400
100 00:00:08 1,072 -1.378 11.900 17.800 20.700 4.366 13.500
101 00:00:08 1,025 -1.015 11.300 17.600 20.700 4.648 13.600
102 00:00:08 989 -1.015 11.400 17.400 21.100 4.652 13.500
103 00:00:08 992 -0.870 12.200 17.400 21.300 4.800 13.600
104 00:00:08 1,073 -1.015 11.800 17.800 21.100 4.648 13.600
105 00:00:08 1,140 -1.233 12.500 18.200 21.400 4.456 13.500
106 00:00:08 1,149 -1.305 12.300 18.200 21.800 4.410 13.600
107 00:00:08 1,144 -1.305 11.400 18.200 21.900 4.410 13.500
108 00:00:08 1,189 -1.305 11.600 18.400 21.400 4.410 13.600
109 00:00:08 1,275 -1.668 11.600 18.600 21.800 3.998 13.500
110 00:00:08 1,310 -1.813 11.600 18.800 21.300 3.188 13.400
111 00:00:09 1,317 -1.885 11.200 18.800 22.500 3.184 13.600
112 00:00:09 1,345 -1.958 11.600 19.000 22.600 3.872 13.600
113 00:00:09 1,412 -2.176 11.600 19.200 22.600 3.804 13.600
114 00:00:09 1,475 -2.321 11.900 19.400 22.500 3.740 13.600
115 00:00:09 1,485 -2.393 12.200 19.600 22.600 3.686 13.600
116 00:00:09 1,508 -2.466 12.500 19.600 22.500 3.682 13.600
117 00:00:09 1,574 -2.466 12.600 20.000 23.100 3.710 13.600
118 00:00:09 1,629 -2.538 12.700 20.400 23.200 3.680 13.600
119 00:00:09 1,665 -2.538 12.000 20.600 23.500 3.694 13.700
120 00:00:09 1,701 -2.756 12.900 21.000 24.000 3.648 13.600
121 00:00:09 1,761 -2.248 13.000 21.400 25.900 3.860 13.700
122 00:00:10 1,828 -1.813 13.000 21.800 24.600 3.346 13.600
123 00:00:10 1,891 -1.885 12.900 22.400 26.500 4.208 13.700
124 00:00:10 1,945 -1.958 13.300 22.800 26.700 4.206 13.700
125 00:00:10 1,999 -2.031 13.500 23.200 26.900 4.244 13.700
126 00:00:10 2,067 -2.103 12.700 23.400 27.100 4.168 13.700
127 00:00:10 2,137 -2.103 13.500 23.800 28.000 4.168 13.800
128 00:00:10 2,207 -1.958 13.000 24.000 23.400 3.456 13.700
129 00:00:10 2,257 -1.958 13.000 24.200 28.200 4.274 13.800
130 00:00:10 2,328 -2.103 13.000 24.600 28.100 4.172 13.800
131 00:00:10 2,406 -2.176 12.800 25.000 27.600 3.366 13.800
132 00:00:10 2,477 -2.248 13.000 25.200 24.400 3.310 13.700
133 00:00:11 2,519 -2.103 12.400 25.400 28.600 4.196 13.800
134 00:00:11 2,612 -2.176 12.500 25.400 28.500 4.172 13.900
135 00:00:11 2,715 -2.248 12.600 25.600 28.200 4.094 13.900
136 00:00:11 2,759 -2.321 12.700 25.600 28.500 4.074 13.900
137 00:00:11 2,791 -2.393 12.500 25.600 22.800 3.236 13.800
138 00:00:11 2,864 -2.828 12.500 26.000 25.600 3.704 13.900
139 00:00:11 2,917 -3.771 12.500 27.200 24.400 3.408 13.900
140 00:00:11 2,942 -5.076 12.500 28.000 20.600 2.424 13.900
141 00:00:11 2,965 -6.164 12.200 28.000 17.700 2.134 13.900
142 00:00:11 2,963 -7.977 12.600 28.000 6.900 1.870 13.900
143 00:00:11 2,832 -9.573 12.800 27.200 3.800 1.726 13.900
144 00:00:11 2,735 -10.298 13.300 26.800 1.400 1.652 13.900
145 00:00:12 2,615 -10.588 13.200 26.000 0.000 1.594 13.900
146 00:00:12 2,489 -10.878 12.900 25.200 0.000 1.536 13.800
147 00:00:12 2,358 -10.950 14.000 24.800 0.000 1.520 13.800
148 00:00:12 2,226 -10.878 15.200 24.200 0.000 1.512 13.800
149 00:00:12 2,126 -10.660 15.600 23.800 0.000 1.550 13.700
150 00:00:12 2,006 -10.588 15.700 23.400 0.000 1.542 13.700
151 00:00:12 1,901 -10.443 16.400 22.400 0.000 1.580 13.700
152 00:00:12 1,798 -10.080 15.900 21.600 0.000 1.622 13.700
153 00:00:12 1,664 -7.905 15.200 20.400 19.200 1.740 13.600
154 00:00:12 1,556 -5.729 14.400 19.800 20.900 2.054 13.600
155 00:00:12 1,578 -4.061 14.800 19.600 21.000 2.576 13.600
156 00:00:13 1,518 -3.698 13.500 19.400 21.700 3.242 13.600
157 00:00:13 1,590 -2.611 14.500 20.000 25.300 3.656 13.700
158 00:00:13 1,648 -1.958 16.800 20.600 26.100 3.924 13.600
159 00:00:13 1,519 -1.305 19.700 19.600 28.800 4.210 13.600
160 00:00:13 1,597 -0.725 17.700 20.200 32.800 4.676 13.600
161 00:00:13 1,630 -0.218 16.700 20.400 29.400 4.108 13.500
162 00:00:13 1,602 -0.073 16.300 20.000 33.800 5.186 13.600
163 00:00:13 1,670 -0.073 14.600 20.600 34.400 5.188 13.600
164 00:00:13 1,668 -0.073 14.600 20.600 34.600 5.188 13.700
165 00:00:13 1,688 0.000 13.900 20.800 34.800 5.294 13.600
166 00:00:13 1,746 0.073 13.200 21.200 35.500 5.302 13.600
167 00:00:13 1,732 0.145 12.900 21.000 36.500 5.372 13.600
168 00:00:14 1,784 0.145 12.700 21.400 37.100 5.372 13.700
169 00:00:14 1,812 0.218 12.600 21.600 37.200 5.444 13.700
170 00:00:14 1,819 0.218 12.600 21.600 32.200 4.380 13.400
171 00:00:14 1,860 0.218 13.000 22.000 37.500 5.444 13.700
172 00:00:14 1,886 0.290 12.200 22.200 37.500 5.518 13.700
173 00:00:14 1,904 0.290 12.300 22.400 37.700 5.518 13.700
174 00:00:14 1,937 0.363 12.000 22.600 38.400 5.588 13.700
175 00:00:14 1,966 0.435 12.000 22.800 40.100 5.658 13.700
176 00:00:14 1,992 0.580 12.100 23.000 41.700 5.806 13.700
177 00:00:14 2,025 0.580 11.900 23.000 41.900 5.806 13.700
178 00:00:14 2,067 0.653 12.400 23.000 36.800 4.722 13.500
179 00:00:15 2,077 0.725 12.300 23.000 42.500 5.950 13.700
180 00:00:15 2,125 0.798 11.500 23.200 43.900 5.958 13.800
181 00:00:15 2,158 0.798 12.400 23.200 44.200 5.958 13.800
182 00:00:15 2,162 0.798 11.700 23.200 44.800 4.786 13.700
183 00:00:15 2,206 0.870 11.800 23.200 44.300 6.034 13.700
184 00:00:15 2,241 1.015 11.900 23.200 45.900 6.180 13.800
185 00:00:15 2,244 1.088 11.700 23.200 47.200 6.254 13.800
186 00:00:15 2,319 1.160 11.300 23.400 45.300 5.078 13.600
187 00:00:15 2,325 1.233 11.200 23.400 49.700 6.400 13.800
188 00:00:15 2,366 1.305 11.300 23.400 43.500 5.198 13.600
189 00:00:15 2,411 1.450 11.500 23.400 50.200 6.626 13.800
190 00:00:15 2,420 1.595 11.400 23.400 50.300 6.714 13.800
191 00:00:16 2,485 1.668 11.200 23.400 50.700 6.790 13.800
192 00:00:16 2,496 1.740 11.100 23.400 51.100 6.864 13.800
193 00:00:16 2,543 1.813 10.900 23.400 52.200 6.950 13.900
194 00:00:16 2,576 1.885 10.300 23.200 52.600 7.030 13.700
195 00:00:16 2,621 2.031 11.000 23.200 48.800 5.764 13.700
196 00:00:16 2,639 2.031 10.600 23.200 55.300 5.768 13.900
197 00:00:16 2,709 2.176 11.000 23.200 55.600 5.900 13.900
198 00:00:16 2,699 2.248 12.400 23.000 55.900 5.906 13.900
199 00:00:16 2,765 2.321 12.100 23.000 50.700 5.980 13.800
200 00:00:16 2,836 2.611 12.300 22.800 55.500 6.238 13.900
201 00:00:16 2,820 2.683 12.700 22.800 55.700 6.300 13.900
202 00:00:17 2,907 2.828 12.600 22.800 55.900 6.380 14.000
203 00:00:17 2,934 2.973 12.100 22.600 56.400 6.458 14.000
204 00:00:17 2,986 3.046 12.900 22.600 50.200 6.592 13.800
205 00:00:17 3,028 3.046 12.600 22.600 55.300 6.598 13.900
206 00:00:17 3,083 3.191 12.300 22.600 56.100 6.664 14.000
207 00:00:17 3,123 3.191 12.300 22.600 55.300 6.726 13.900
208 00:00:17 3,163 3.408 12.900 22.400 55.200 6.856 14.000
209 00:00:17 3,221 3.481 12.300 22.400 56.300 6.922 14.000
210 00:00:17 3,264 3.553 12.200 22.400 52.500 7.050 13.800
211 00:00:17 3,310 3.698 11.800 22.200 56.400 7.060 14.100
212 00:00:17 3,353 3.771 11.800 22.200 50.100 7.182 13.800
213 00:00:17 3,418 3.844 12.200 22.200 56.400 7.128 14.100
214 00:00:18 3,461 3.989 11.600 22.200 56.100 7.200 14.100
215 00:00:18 3,499 4.061 11.800 22.000 55.600 7.262 14.100
216 00:00:18 3,558 4.061 11.700 22.000 54.700 7.262 14.000
217 00:00:18 3,631 3.989 11.200 22.200 56.400 7.202 14.100
218 00:00:18 3,655 4.134 11.100 22.000 54.600 7.272 14.100
219 00:00:18 3,707 4.061 11.100 22.000 50.900 7.266 14.000
220 00:00:18 3,782 4.134 11.600 22.000 53.500 7.276 14.100
221 00:00:18 3,818 4.351 12.300 22.000 51.500 7.478 13.900
222 00:00:18 3,877 4.424 11.800 21.800 55.900 7.424 14.200
223 00:00:18 3,949 4.641 11.700 21.800 55.600 7.568 14.100
224 00:00:18 3,992 4.859 11.600 21.600 53.600 7.654 14.000
225 00:00:19 4,054 5.149 11.900 21.400 55.100 7.814 14.100
226 00:00:19 4,105 5.439 11.900 21.400 55.300 7.972 14.100
227 00:00:19 4,170 5.656 11.700 21.200 47.800 8.118 14.000
228 00:00:19 4,191 6.019 12.000 21.000 46.500 8.284 14.000
229 00:00:19 4,271 6.309 11.400 20.800 52.600 8.440 14.200
230 00:00:19 4,351 6.672 11.900 20.600 49.400 8.664 14.000
231 00:00:19 4,357 6.962 12.200 20.400 49.700 8.818 14.200
232 00:00:19 4,470 7.179 12.100 20.400 46.300 8.902 14.000
233 00:00:19 4,496 7.760 11.900 20.000 51.000 9.208 14.100
234 00:00:19 4,540 8.122 12.000 20.000 46.800 9.434 14.000
235 00:00:19 4,628 8.557 11.500 19.800 51.400 9.674 14.200
236 00:00:20 4,696 8.920 11.800 19.800 46.400 9.834 14.100
237 00:00:20 4,729 9.282 11.700 19.600 45.700 10.052 14.000
238 00:00:20 4,856 9.645 11.700 19.600 46.000 10.198 14.100
239 00:00:20 4,836 9.863 11.000 19.600 50.500 10.342 14.200
240 00:00:20 4,907 10.080 11.700 19.600 45.200 10.410 14.000
241 00:00:20 4,987 10.443 11.700 19.600 45.700 10.606 14.100
242 00:00:20 4,998 10.660 11.100 19.600 48.500 10.682 14.100
243 00:00:20 5,066 10.733 11.400 19.600 44.700 10.742 14.000
244 00:00:20 5,119 10.805 11.700 19.600 44.400 10.748 14.100
245 00:00:20 5,206 10.805 11.000 19.800 45.100 10.748 14.000
246 00:00:21 5,174 10.660 11.800 19.800 44.000 10.680 14.000
247 00:00:21 5,310 10.515 11.400 20.200 44.400 10.608 14.000
248 00:00:21 5,279 10.298 11.800 20.200 46.700 10.532 14.000
249 00:00:21 5,246 10.588 12.000 20.000 46.100 10.672 14.200
250 00:00:21 5,322 10.515 11.700 20.200 45.000 10.608 14.100
251 00:00:21 5,426 10.370 11.900 20.600 46.100 10.536 14.000
252 00:00:21 5,355 10.370 11.400 20.400 47.500 10.536 14.000
253 00:00:21 5,480 10.660 11.800 20.600 45.600 10.680 14.000
254 00:00:21 5,476 10.805 11.200 20.400 46.000 10.748 14.100
255 00:00:21 5,547 10.805 11.400 20.600 45.600 10.748 14.000
256 00:00:21 5,598 10.443 11.500 20.800 44.200 10.606 14.000
257 00:00:22 5,541 10.080 11.600 21.000 45.300 10.400 14.100
258 00:00:22 5,629 9.573 12.000 21.200 45.000 10.192 14.000
259 00:00:22 5,703 9.573 11.400 21.400 43.600 10.198 14.000
260 00:00:22 5,661 8.485 11.300 21.800 40.000 9.658 14.100
261 00:00:22 5,854 7.397 11.900 22.600 40.200 9.232 14.100
262 00:00:22 5,828 7.542 11.700 22.400 40.300 9.290 14.000
263 00:00:22 5,844 7.614 11.400 22.400 41.400 9.296 14.000
264 00:00:22 5,986 6.672 11.700 23.000 32.700 8.800 14.000
265 00:00:22 5,537 -7.832 11.600 33.000 3.600 1.680 14.200
266 00:00:22 5,421 -9.790 12.100 34.200 1.500 1.542 14.200
267 00:00:22 5,260 -10.733 17.400 34.200 0.000 1.464 14.200
268 00:00:23 5,081 -11.095 16.300 34.200 0.000 1.396 14.200
269 00:00:23 4,903 -11.095 15.500 34.200 0.000 1.400 14.200
270 00:00:23 4,750 -11.095 15.200 34.200 0.000 1.400 14.200
271 00:00:23 4,588 -11.095 15.000 34.200 0.000 1.400 14.200
272 00:00:23 4,439 -11.023 15.000 33.800 0.000 1.438 14.200

 

There's nothing in this log that's obviously wrong. The sample rate is fast enough that it can be trusted, and the AFR's are between 11:1 and 12:1 in the area in question. What is this ECU? Is this the one that can't control split? I don't know how this thing controls injector staging. Do you just allocate injector duty between primary and secondary based on RPM and boost?

As for the resistor question, I can't really answer that. Most people here are using EMS's that can't directly drive low impedence injectors with using resistors. I would think that if your ECU has a built in peak-and-hold driver then it shouldn't be an issue at all.

 

Its a EMS Stinger nosplit cont rol)

re: staging, It simlpy allows you to select staging on/off......if on, you then select staged percentage depenging on injector size configuration. No further options.

 

it doesn't have a staging rpm or boost level? it doesn't allow you to ramp up secondary injector duty cycle, it just suddenly goes from 100% on the primary to whatever staging percentage you select?

it sounds like this EMS is not designed for rotary engines at all

 

Actually I've had this baby running quite well for the past year or so without problems with the stock 550/850 injectors. Hesitation started when i street ported, changed the inj to 1000/1600 and retuned.

Re: staging. this is taken from the Stinger manual.

hesitation ever since I ported and changed the injectors and re-tuned

Re: staging......this it taken from the Stinger manual

Staged Injection

Staged injection is for engines with Staged fuel injectors (ie; two injectors per cylinder). If your engine is not using Staged injectors then select "OFF".

WARNING!!
DO NOT SELECT STAGED INJECTION FOR NON-STAGED INJECTED ENGINES AS THIS WILL CAUSE ENGINE DAMAGE.

The Staged adjustments are located under the Trim Button off the 3D
Tuning page.

When a staged number is selected in the staged amount field, the ecu will
bring on the staged injectors Automatically, when it sees the primary
injectors approaching 100% Duty.
To test the Staged fuel amount the user can force the ecu to enable the Staged
injection earlier by clicking on the "Force Staged inj On" check box.

Via experimental testing, change the staged number until the correct air fuel ratio is achieved.

For engine configurations with primary and secondary injectors of the same size,
set the staged number to 57.6% and no need for further adjustment.

If the secondaries are larger that the primary injectors, the staged number will be
smaller.
If the secondaries are smaller that the primary injectors, the staged number will be larger.

 

A normal 4 cycle engine stage will not work for a FD rotary engine since the throttle body and air flow through ports are way different. A 4 cycle engine only has one set of TB openings and only one set of intake openings where as rotaries have multiple.

A FDs secondary ports open for air flow well before fuel is added under cruise and light acceleration. The stock secondary injectors come on around 40% primary duty cycle. Since the secondary openings in the throttle body are about 2/3 of the total area, after staging, the primaries only flow about 1/3 the fuel with the secondary injectors flowing 2/3 the fuel.

I was the first to use the DATALOGIT with a PFC, log what happens, and post it in the PFC forums years ago. Up to that point, most tuned PFC staging was off even though it was for a rotary. The default values even for a stock engine were not optimized. The informed now know better.

Logging the primary and secondary injector values along with overall duty cycle and viewing it in chart playback mode reveals what is happening and when.

 

Based on this, I recommend you set "Force Staged inj On" and start with a value of 40%. Then progressively drop the value by maybe 3 or 5 percent, until you get a rich spot (you may or may not see it on the wideband). After it goes rich, do the opposite and increase the staging % a little bit to see if you can find a value that's not too rich or not too lean. Your wideband is probably not showing the whole picture here for whatever reason.

Also, Chuck is right and I suspected it as well. The staging on your EMS was designed for heavily modified 4 cylinder engines with single stage TB's. In that kind of application the secondary injectors are not going to come on in part throttle much, so a smooth blending of the two injectors isn't as crucial.



On the 2009 Rx-8's you can see how complicated and non linear the staging is. The series 2 (09+) 13B-MSP Renesis has 2 primary and 2 secondary injectors like the FD, but a single bore throttlebody that is computer controlled (drive-by-wire). The secondary ports open through a valve in the LIM controlled by a vacuum actuator.

 

Thanks for the input guys.

Well I know that I will be stuck with this ECU for a while. By the way, It was designed with rotary in mind since it has mazda 13b rotary as an option in the ecu ignition setup list, and does have 13b listed in othere area of the intallation setup.

I have had it running the stock injectors staged really well, I guess the extra air flow from the porting, or the transition for high to low inpedance injectors is the cause.
I will do a wot log which does not give hesitation, and compare it to the part throttle log and to see the difference in AFR's and pressure at specific rpm and try to fine tune it.

 

Any other suggestions are welcome.

 

Would it correct to rule out a weak ignition as the cause of the part throttle hesitation between 4500 and 5500 since the hesitation totaly disapears if full throttle is used?

 

I am beginning to get your point. Should the secondarys come on as the sec.ports open, should they come on after the ports open or should they be already on when the ports open.

Also are there any mods forthe FD throttle body? Probably one to make the ports open simultaneously?

 

There is a way to adjust the opening of the secondary throttle plates relative to the primary throttle plates. I have done it on the FC turbo throttlebody but not the FD. The two have the same basic design though, although things are different locations. This procedure is not in the FD service manual.



You can see that there's a little arm connecting the secondary butterflies to the primary. Once the primary throttle valve reaches a particular angle, the secondaries begin to open. This FSM procedure calls for measuring how far open the primary throttle is when the secondaries crack open. The smaller the clearance between the primary butterfly and the TB bore, the sooner the secondaries open. The larger the clearance, the later the secondaries open. The clearance itself is very difficult to measure accurately. The TB bore is round, and feeler gauges are flat and square. Your best bet is to find that adjuster and start fiddling with it.

What you could do though is measure TPS resistance when the secondary throttle plates open. Then set the secondary plates to open where the TPS resistance is some percentage higher (more resistance = less TPS voltage if it were connected to the harness, and thus a smaller throttle opening). That would make them open earlier. But it sound like you want them to open later, after the secondary injectors come online? Then you would want TPS resistance to decrease.

 

Thanks for the info. In my case, did you say I need them to open later?

 

well it depends what's happening. if you have a lean spot because the secondary butterflies are opening before the secondary injectors come online, you may want to try opening them earlier and see if it does anything.

but from an engineering perspective it's not a requirement that secondary injectors fire while secondary butterflies are open. The series 3 GSL-SE used primary injectors only, two 680cc top feeds for an n/a engine.

 

With the above mentioned engine, I would assume that the stock ecu would increase the injector duty at that point where it openes the secondary ports to compensate for the exta airflow. But in my case there is no coordination between the two events. Do you agree?

Someone told be that It could be that It because I use too much oil in my premix which could be killing my plugs, and also creating too heavy of a mixture for my plugs to light off. My ignition is stock and I am using 1oz castrol 2T oil to 1 gal of gas. What do you think?