Ignition problem above 5000 RPM
Ignition problem above 5000 RPM
8.6:1 Arias pistons
Pauter Rods
650cc injectors
APS TT
UTEC
Brand new 1 step colder plugs
JWT Flywheel
Car runs great, but feels like it 'breaks up' above 5,000 RPM.
I've datalogged a few runs and it appears that my RPMs spike while accelerating. I don't have access to my logs on this computer, but the RPM looks like this:
RPM
4761
4830
4887
5274
4945
5020
5042
5128
5482
5128
5184
5602
5367
5350
5564
5500
5920
5564
5621
5630
5941
6082
6161
6230
TPS on this run is consistant around 60% (+/-2)
I'm in the 50% load table the entire time in the UTEC
A/F starts at 11.7 and slowly drops to 11.2
Timing starts at 14.2 and slowly climbs to 17.1 with no big jumps
Boost starts at 9lbs, peaks at 10.1 and trails off to 9.7
My original thought was the spark plugs, so I replaced them, gapping the new plugs at .035. The plugs I pulled out looked good, and were all gapped at .035. The problem still exists.
Anyone have any ideas?
The only thing I can think of at this point is noise on the crank angle wire. The problem is the same at lower boost (6.5) and higher boost (10). I do have a shielded crank angle sensor, but it was hacked up a bit to work with the UTEC. I will verify that the drain was connected to the ECU's sensor ground terminal.
If the crank angle sensors signal is noisy it could be causing the car to inject/fire at the wrong time, which could be the hesitation I'm feeling.
I'm not getting any knock counts from the UTEC.
The problem isn't always there, sometimes it is, sometimes it isn't. It seems like it happens less when the car is cold, but that might not be the case.
Pauter Rods
650cc injectors
APS TT
UTEC
Brand new 1 step colder plugs
JWT Flywheel
Car runs great, but feels like it 'breaks up' above 5,000 RPM.
I've datalogged a few runs and it appears that my RPMs spike while accelerating. I don't have access to my logs on this computer, but the RPM looks like this:
RPM
4761
4830
4887
5274
4945
5020
5042
5128
5482
5128
5184
5602
5367
5350
5564
5500
5920
5564
5621
5630
5941
6082
6161
6230
TPS on this run is consistant around 60% (+/-2)
I'm in the 50% load table the entire time in the UTEC
A/F starts at 11.7 and slowly drops to 11.2
Timing starts at 14.2 and slowly climbs to 17.1 with no big jumps
Boost starts at 9lbs, peaks at 10.1 and trails off to 9.7
My original thought was the spark plugs, so I replaced them, gapping the new plugs at .035. The plugs I pulled out looked good, and were all gapped at .035. The problem still exists.
Anyone have any ideas?
The only thing I can think of at this point is noise on the crank angle wire. The problem is the same at lower boost (6.5) and higher boost (10). I do have a shielded crank angle sensor, but it was hacked up a bit to work with the UTEC. I will verify that the drain was connected to the ECU's sensor ground terminal.
If the crank angle sensors signal is noisy it could be causing the car to inject/fire at the wrong time, which could be the hesitation I'm feeling.
I'm not getting any knock counts from the UTEC.
The problem isn't always there, sometimes it is, sometimes it isn't. It seems like it happens less when the car is cold, but that might not be the case.
Is it even possible for a motor to flucuate that much? The last bolded data point has a 400 RPM spike under constant acceleration. I'm really leaning towards it being a crank angle problem, and the UTEC not knowing the true crank position, causing my timing to be off.
I'll post some charts tonight hopefully, getting ready to leave work right now.
I'll post some charts tonight hopefully, getting ready to leave work right now.
I would say adjust your timing DOWN and try that.. If I remember correctly, timing in that high of a range is too high.. I could be wrong but I think you should he around 14.5-15 and dropping on pump gas in that rpm/ % column..
I'm running 94 octane gas and I really don't want to go up to 100.
My timing looks like this:
I got the timing map from a trusted tuner/sponsor on my350z.com. I believe it to be on the conservative side, but I don't know much about timing on this motor (or any other motor, for that matter).
My goal is to run my timing a bit on the conservative side.
Right now, I barely make it in to the 60% load column
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that timing graph looks very ugly, i think it needs some major work.
that might be some of your issue, it jumps around like crazy, some spots too low, some too high.
i know i sent you a base map for APS a long time ago i had, but i know you have had some other ones as well.
IM me man, sorry i missed your message earlier..
that might be some of your issue, it jumps around like crazy, some spots too low, some too high.
i know i sent you a base map for APS a long time ago i had, but i know you have had some other ones as well.
IM me man, sorry i missed your message earlier..
Thanks for your advice. This is the same map that I have always ran, and I actually compared it to the map you sent me and that is when I started to get concerned. I thought that was a TN car though?
Is the map you sent me better to run? I believe it was mapped 1-20psi, just like my car is. The timing is very different, especially up top.
Is the map you sent me better to run? I believe it was mapped 1-20psi, just like my car is. The timing is very different, especially up top.
OK, I pulled a ton of timing out of the map, and I still have the same problem.
My A/F looks great, my UTEC isn't pulling timing, and nothing else seems out of the ordinary. Anyone else got any ideas?
My A/F looks great, my UTEC isn't pulling timing, and nothing else seems out of the ordinary. Anyone else got any ideas?
Originally Posted by KPierson
8.6:1 Arias pistons
Pauter Rods
650cc injectors
APS TT
UTEC
Brand new 1 step colder plugs
JWT Flywheel
Car runs great, but feels like it 'breaks up' above 5,000 RPM.
I've datalogged a few runs and it appears that my RPMs spike while accelerating. I don't have access to my logs on this computer, but the RPM looks like this:
RPM
4761
4830
4887
5274
4945
5020
5042
5128
5482
5128
5184
5602
5367
5350
5564
5500
5920
5564
5621
5630
5941
6082
6161
6230
TPS on this run is consistant around 60% (+/-2)
I'm in the 50% load table the entire time in the UTEC
A/F starts at 11.7 and slowly drops to 11.2
Timing starts at 14.2 and slowly climbs to 17.1 with no big jumps
Boost starts at 9lbs, peaks at 10.1 and trails off to 9.7
My original thought was the spark plugs, so I replaced them, gapping the new plugs at .035. The plugs I pulled out looked good, and were all gapped at .035. The problem still exists.
Anyone have any ideas?
The only thing I can think of at this point is noise on the crank angle wire. The problem is the same at lower boost (6.5) and higher boost (10). I do have a shielded crank angle sensor, but it was hacked up a bit to work with the UTEC. I will verify that the drain was connected to the ECU's sensor ground terminal.
If the crank angle sensors signal is noisy it could be causing the car to inject/fire at the wrong time, which could be the hesitation I'm feeling.
I'm not getting any knock counts from the UTEC.
The problem isn't always there, sometimes it is, sometimes it isn't. It seems like it happens less when the car is cold, but that might not be the case.
Pauter Rods
650cc injectors
APS TT
UTEC
Brand new 1 step colder plugs
JWT Flywheel
Car runs great, but feels like it 'breaks up' above 5,000 RPM.
I've datalogged a few runs and it appears that my RPMs spike while accelerating. I don't have access to my logs on this computer, but the RPM looks like this:
RPM
4761
4830
4887
5274
4945
5020
5042
5128
5482
5128
5184
5602
5367
5350
5564
5500
5920
5564
5621
5630
5941
6082
6161
6230
TPS on this run is consistant around 60% (+/-2)
I'm in the 50% load table the entire time in the UTEC
A/F starts at 11.7 and slowly drops to 11.2
Timing starts at 14.2 and slowly climbs to 17.1 with no big jumps
Boost starts at 9lbs, peaks at 10.1 and trails off to 9.7
My original thought was the spark plugs, so I replaced them, gapping the new plugs at .035. The plugs I pulled out looked good, and were all gapped at .035. The problem still exists.
Anyone have any ideas?
The only thing I can think of at this point is noise on the crank angle wire. The problem is the same at lower boost (6.5) and higher boost (10). I do have a shielded crank angle sensor, but it was hacked up a bit to work with the UTEC. I will verify that the drain was connected to the ECU's sensor ground terminal.
If the crank angle sensors signal is noisy it could be causing the car to inject/fire at the wrong time, which could be the hesitation I'm feeling.
I'm not getting any knock counts from the UTEC.
The problem isn't always there, sometimes it is, sometimes it isn't. It seems like it happens less when the car is cold, but that might not be the case.
But my coil pack issue would be consistant at a certain RPM, and only at that RPM...It would back fire and stutter then drive through it..
Man I dont know without being able to actually be there and see what the car is actually doing..
Does the car TOTALLY lose power, like its not getting enough fuel or slight loss in power?
Does the car TOTALLY lose power, like its not getting enough fuel or slight loss in power?
Code:
RPM TPS Load A/F ??? OEM Fuel UTEC ??? Cell Time Time 3627 89 10 14.6 9.86 27.4 29.9 20.3 -1 3635 96 20 12.5 10.09 27.3 30.8 19.3 -1 3667 96 20 12.5 10.31 24.1 31.1 18 -1 3926 96 20 11.1 11.74 23.5 34.5 17.4 -1 3753 95 30 11.6 13.2 24.6 40.6 17 -1 3889 94 30 11.6 13.59 24.2 42.8 16.4 -1 3944 92 40 11.1 14.08 23.4 45.8 16.1 -1 3871 92 40 11.4 14.46 23 47.5 16 -1 3753 92 40 11.4 14.46 23.4 46.5 16 -1 4084 91 40 11.7 14.46 23 45.8 15.9 -1 4074 89 40 11.6 14.34 23 48 16.1 -1 4177 89 40 11.6 14.28 23.2 47.9 16.2 -1 4198 89 40 11.7 14.23 23.6 49.2 15.7 -1 4100 91 40 11.8 14.19 23.4 50 15.8 -1 4065 95 40 11.8 14.21 22 49.4 15.9 -1 4278 96 40 11.7 14.16 22.5 49.5 15.7 -1 4340 95 40 11.7 14.6 22.3 52 15.5 2 4278 94 40 11.6 14.25 22.2 53 15.4 -1 4329 94 40 11.4 14.35 20.1 53.1 15.3 -1 4385 93 40 11.4 14.43 21.2 52.5 15.8 -1 4535 92 40 11.7 14.45 21.4 55 15.5 -1 4444 93 40 11.7 14.48 20.5 54.9 15.3 -1 4504 92 40 11.7 14.53 20.2 51.8 15.3 -1 4714 92 40 11.6 14.57 21.7 56.3 15.2 -1 4397 92 40 11.7 14.66 21.4 55.1 15.2 -1 4403 92 40 11.7 14.67 21.7 54.3 15.2 -1 4510 92 40 11.5 14.71 21.2 59.6 15 -1 4468 92 40 11.4 14.81 21.5 58 15 -1 4553 91 40 11.4 14.82 21.3 57.8 15.2 -1 4803 92 40 11.4 14.92 21.2 56.7 15.2 -1 4997 92 40 11.4 14.93 23.3 57.3 15.3 -1 4880 92 40 11.4 15.03 23 58.2 15.6 -1 4930 92 40 11.4 15.05 23.1 63.8 15.9 -1 4975 92 40 11.4 15.11 21.5 62.3 16 -1 4803 92 40 11.5 15.01 23.5 63.5 16.1 -1 4803 92 40 11.6 15.17 22.1 63.6 16.1 -1 4866 92 40 11.6 15.31 22.5 64.6 16.1 -1 4938 92 40 11.4 15.2 23.4 63.2 16.2 -1 5136 93 40 11.2 15.5 21.2 68.9 16.1 -1 5367 93 40 11.2 15.68 20.9 68.2 16 -1 5393 92 40 11.3 15.73 21.3 66.2 16 -1 5167 92 40 11.3 15.86 20.3 66.2 16 -1 5307 93 40 11.3 16.06 20.9 73 16 -1 5151 92 40 11.2 16.02 21.6 68.8 15.9 -1 5473 92 40 11.2 16.18 21.1 73.8 15.8 -1 5136 93 40 11.1 16.1 21.2 75.5 15.8 -1 5159 93 40 11.1 16.11 21.1 75.1 15.3 -1 5592 92 40 11.1 16.34 21.3 76 15.2 -1 5324 92 50 11 16.67 20.9 74.1 15.2 -1 5574 93 40 11 16.6 21.5 77.6 15.2 -1 5455 92 40 12.7 16.59 21.1 77.8 15.2 -1 5350 92 40 12.7 16.78 21.4 80.5 15.1 -1 5668 93 40 12.7 16.94 21.4 76.6 15.1 -1 5668 93 40 13.4 16.85 21.3 81.1 14.9 -1 5767 93 50 13.4 17.01 20.8 83.6 14.9 -1 5583 94 40 13.4 16.9 20.9 83.8 15 -1 5574 94 50 13.4 17.06 21 86.2 15 -1 5649 94 50 13.4 17.08 20.9 85.8 15 -1 5688 94 50 13.4 17.23 21.3 86.4 15.1 -1 6105 94 40 13.4 17.11 21.1 85.8 15.1 -1 5727 94 50 13.4 17.14 22.4 84.9 15.2 -1 5747 93 50 13.4 17.15 22 88.4 15.2 -1 6071 93 50 13.4 17.33 22 88.9 15.1 -1 5807 94 50 11 17.2 22.4 86.4 15 -1 5868 93 50 17.3 17.24 23.4 84.9 14.9 -1 6337 93 50 17.3 17.26 23.8 90.8 14.9 -1 6373 87 50 17.3 17.27 23.8 90.5 15.1 -1 6016 34 50 17.3 17.32 24.2 85.6 14.8 -1
Again, notice how the RPM jumps all over the place.
At 5393 my OEM timing drops a degree, is that the ECU pulling timing because of knock?
Also, what is the right most column? I have no idea what that data is.
Also, please disregard the A/F readings at the end. I'm not sure why it did that, but occasionally my logs look like that when the A/F was really closer to 11.2:1.
How do you check the coil packs? Did you just replace them and the problem went away or did you have something that pointed you in that direction?
When it does this its not a total loss of power, just a slight hesitation.
I have a JWT flywheel that I've had for a very long time. This problem just started very recently. I'm not ruling it out, but I'm not thinking this has anything to do with it.
So, anyone have any feedback from the logs?
Originally Posted by al v
Please , check the ground wire from the UTEC to the chassis, looks like the Utec hesitation problem , very common in the G35 ,remove your ecu and check both wire sides.
I had to ground my UTEC twice.. I grounded it with the standard wire that is supplied plus I grounded again from one of the UTEC nuts that holds the ECU and UTEC together and that went to another nut/bolt..
K
i have installed many many utecs and have yet to ground one, i dont really think that is the issue on any of them.
kevin, yes, when the car is knocking and the stock timing will be pulled. i dont think your car is pulling stock timing though. sorry i didnt have time to get you a remapped timing map.
also, do this, cut the carpet out from under your gas pedal, i would bet money that its very thick and keeping your car from reaching full tps...
kevin, yes, when the car is knocking and the stock timing will be pulled. i dont think your car is pulling stock timing though. sorry i didnt have time to get you a remapped timing map.
also, do this, cut the carpet out from under your gas pedal, i would bet money that its very thick and keeping your car from reaching full tps...
I'll reground it tonight (or sometime this week). I wasn't thinking that was the problem because A. it just started doing it and B. I thought it was a total loss of power above a certain RPM.
I'll also look in to the accelerator pedal thing.
Thank you all for your help, I know its hard to diagnose problems over the internet, but the wide variety of ideas and thoughts really helps out in the troubleshooting process.
I'll also look in to the accelerator pedal thing.
Thank you all for your help, I know its hard to diagnose problems over the internet, but the wide variety of ideas and thoughts really helps out in the troubleshooting process.
Another thought I had was to redline the car with no boost and see if the ignition problem still exists. I'm not really sure what that would tell me, but it would be interesting to see.
Originally Posted by Audible Mayhem
i have installed many many utecs and have yet to ground one, i dont really think that is the issue on any of them.
kevin, yes, when the car is knocking and the stock timing will be pulled. i dont think your car is pulling stock timing though. sorry i didnt have time to get you a remapped timing map.
also, do this, cut the carpet out from under your gas pedal, i would bet money that its very thick and keeping your car from reaching full tps...
kevin, yes, when the car is knocking and the stock timing will be pulled. i dont think your car is pulling stock timing though. sorry i didnt have time to get you a remapped timing map.
also, do this, cut the carpet out from under your gas pedal, i would bet money that its very thick and keeping your car from reaching full tps...
The issue above looks like a classic chassis ground problem try grounding from the ecu bolt and the black wire on the accessory plug. Also make sure your factory grounds in the engine bay are ok. If you continue to have the problem contact me at the shop.
Thanks,
Jermaine@turboxs
301-977-4727