Hey all smart people out there...I have a small problem and want to see what everyone thinks about it.

Let me list my mods first so you know what you are working with: Intake, 5/16 Plenum spacer, Test pipes, custom cat back, Tuned with Greddy EMU.

What the car is doing at thee different load points is pulling timing on me. at 4k, 5.5k and 6k my data logs read that my rpm's spike up to 8k (which isnt happening) and the ECU pulls timing down to 0 or less. I will see if I can post a picture of my log through 2nd and 3rd gear. My timing advancement is only 1.5-2 degrees and the during those three load points there is not a rough change in fuel or timing. Lastly, no knock is detected either. Seems a bit weird. My first thought led to a fouled spark plug, and I will have a chance to check those today, but that could be wrong as well.....

Thoughts?

 

Here is the log from the pull....



Time RPM Speed (KPH) INJ RATE TIMING


800 3832 60 0 14.0 26.6
820 3861 60 0 13.9 26.6
840 3889 60 0 13.9 26.5
860 3914 61 0 13.8 26.7
880 3935 61 0 13.9 26.7
900 3950 61 0 13.9 26.4
920 3973 62 0 14.0 26.9
940 4004 62 0 14.0 26.9
960 4035 63 0 14.0 26.9
980 4061 63 0 14.0 26.8
1000 4079 63 0 14.1 26.8
1020 4089 64 0 14.1 25.8
1040 4098 64 0 14.1 26.8
1060 4102 64 0 14.2 26.8
1080 4104 64 0 14.2 27.1
1100 4120 65 0 14.0 26.9
1120 4144 65 0 14.0 26.9
1140 4164 65 0 14.0 27.8
1160 4174 65 0 14.0 26.0
1180 4195 65 0 14.1 25.9
1200 4224 66 0 14.2 25.9
1220 4250 66 0 14.2 25.9
1240 4662 66 0 14.1 -6.9
1260 4293 67 0 14.3 -6.9
1280 4313 67 0 14.3 23.8
1300 4332 68 0 14.3 23.8
1320 4347 68 0 14.3 25.9
1340 4372 68 0 14.2 25.9
1360 4404 69 0 14.2 24.8
1380 4419 69 0 14.2 23.0
1400 4434 69 0 14.3 23.0
1420 4441 69 0 14.6 22.8
1440 4449 70 0 14.6 22.7
1460 4463 70 0 14.8 22.8
1480 4484 70 0 14.5 22.8
1500 4505 70 0 14.5 24.5
1520 4536 71 0 14.5 23.7
1540 4559 71 0 14.6 24.8
1560 4583 71 0 14.3 24.8
1580 4599 72 0 14.5 23.7
1600 4613 72 0 14.5 23.8
1620 4632 72 0 14.7 23.8
1640 4649 73 0 14.6 23.9
1660 4665 73 0 14.8 23.9
1680 4682 73 0 14.6 23.8
1700 4695 73 0 14.6 23.7
1720 4717 74 0 14.8 23.7
1740 4741 74 0 14.8 23.7
1760 4761 74 0 14.8 23.4
1780 4788 75 0 14.8 23.8
1800 4823 75 0 15.0 29.4
1820 4859 76 0 14.7 25.7
1840 4893 76 0 14.6 25.7
1860 4919 77 0 14.7 25.6
1880 4940 77 0 14.8 25.6
1900 4953 77 0 14.8 25.7
1920 4967 78 0 14.8 25.6
1940 4979 78 0 14.8 25.5
1960 4990 78 0 14.7 25.5
1980 5002 79 0 14.7 23.9
2000 5020 79 0 14.5 23.9
2020 5036 79 0 14.5 23.6
2040 5057 79 0 14.6 23.6
2060 5081 79 0 14.7 23.6
2080 5111 80 0 14.7 23.6
2100 5140 80 0 14.8 22.7
2120 5169 81 0 14.9 22.4
2140 5194 81 0 14.9 22.6
2160 5222 82 0 14.8 22.4
2180 5242 82 0 14.6 22.7
2200 5252 82 0 14.7 23.8
2220 5261 83 0 14.7 23.5
2240 5267 83 0 14.8 23.5
2260 5280 83 0 14.5 22.6
2280 5292 83 0 14.6 22.4
2300 5309 83 0 14.6 23.5
2320 5333 84 0 14.9 23.6
2340 5349 84 0 14.7 16.3
2360 5375 84 0 14.7 -9.7
2380 5399 85 0 15.0 21.8
2400 5419 85 0 14.8 23.5
2420 5445 85 0 14.8 23.5
2440 5465 85 0 14.9 23.5
2460 5489 86 0 15.2 23.6
2480 5506 86 0 15.1 23.7
2500 5525 87 0 15.1 23.5
2520 5537 87 0 15.1 23.8
2540 5552 87 0 14.9 24.0
2560 5571 87 0 15.1 23.4
2580 5602 88 0 15.0 22.8
2600 5640 88 0 15.2 23.6
2620 8507 89 0 14.9 -10.2
2640 5699 89 0 15.3 21.9
2660 6250 89 0 15.2 -10.3
2680 6267 90 0 14.9 14.7

 

Just pulled the Throttle body, upper and lower plenum....all very dirty. Port and Polish to come in the morning tomorrow. Pulled all plugs, a bit dirty as well, random gapping on them some on spec at .044 some as high as .052. New plugs tomorrow.

I also had a CEL, checked it with OBDII and came up with P0507 (idle control system)
So I reset the idle using the pedal key technique which landed me a better idle but the CEL was still on afterwards. I didnt drive the car and just disassembled it. I will post again tomorrow when its all put together.

Still no ideas???? ANYONE!!??!?!?!

I think I'm on the right track but who knows....Leave it to the DIY'er to figure it out.

 

Reset the ECU and see if the CEL comes back again.

I tried to read your Cipher logs but the delimiters seem to be missing... even so, the sample log that you posted stops at 6267, not 8,000.

 

Is the 2nd to last column a/f ratio?... if so, it looks like you are running lean which would ‘cause the ECU to pull timing...

Also, JB are you sure he's using Cipher to log? If so - he should be able to clear the CEL with Cipher.

 

Sorry for any confusion but I'm tuned with Greddy E-Manage Ultimate. I have reset the ecu by battery disconnect...didnt do anything.


My logs stop short due to the rev-limiter setting on EMU coming in too early. I will be adjusting that in the next few days once I get this all settled.

I appreciate the responses and would like any additional feedback given. Hopefully the new plugs will be the cure. I will also be porting and polishing the upper and lower plenum and TB tomorrow. (not that this will help, just another mod)

 

Its the Injector opening rate in milliseconds. At this time I do not have wide band o2

The weird thing is the tune was working great....until recently.... no specific event either, just the RPM issue, then the CEL

 

Just finished putting in new plugs, polishing the plenum and TB, still have a CEL and the RPM problem. Weird....

 

Check your Z's O2 sensors and cats.

 

I went on a trip this weekend to IL and after about 300 miles the CEL went off and the tick in the RPM's disappeared...then the car started pulling very hard up top.... whatever!

I think it finally re-learned the idle control and thats what fixed it.