Help me understand IAT/Limp Mode
Help me understand IAT/Limp Mode
Alright, my cars back on the road boosting on 8lbs on the TN reflash.
1-3 Gears, i can go to redline and enjoy. 4-6th gears, if i go past 4k, my car kicks into limp mode and i get a code for High IAT. and obviously the IAT is being read by the MAFS
I also have a meth injection system. Now, from what i have seen on some pics on this forum, the Meth nozzle is being put between the trottle body and the MAFS. In my case where my MAFS volt reading probably shoots way high, would it be possible to inject the meth before the MAFS to cool down the IAT so the MAFS reads 0-5v.
Im kinda confused on this situation and i really dont know what else to do. The MAFS i have on there is brand new. Ive had this limp mode situation before and after i blew the motor. I wanna run on the track before seasons over and i cant if i keep going limp mode.
Thanx and taurran, please keep the flamin to a min.
1-3 Gears, i can go to redline and enjoy. 4-6th gears, if i go past 4k, my car kicks into limp mode and i get a code for High IAT. and obviously the IAT is being read by the MAFS
I also have a meth injection system. Now, from what i have seen on some pics on this forum, the Meth nozzle is being put between the trottle body and the MAFS. In my case where my MAFS volt reading probably shoots way high, would it be possible to inject the meth before the MAFS to cool down the IAT so the MAFS reads 0-5v.
Im kinda confused on this situation and i really dont know what else to do. The MAFS i have on there is brand new. Ive had this limp mode situation before and after i blew the motor. I wanna run on the track before seasons over and i cant if i keep going limp mode.
Thanx and taurran, please keep the flamin to a min.
Originally Posted by wannabuy350z
with some kits the maf sensor is on the intake pipe.
It don't matter since the IAT Sensor is in the MAF Sensor. Unless you go Standalone then there is not much way of getting around this since the ECU is in control with just a flash. Just bite the bullet and get a Utec if cash is limited since on boost Utec don't really care if the IAT is too high. The ECU wont bark with Utec since your IAT won't go up when you are not on boost anyways..
Originally Posted by 350 Rookie
Thanx and taurran, please keep the flamin to a min.
I'm honestly not sure why you'd be throwing a code for high IAT running only 8psi on the kit (never seen the code). The above poster is right that you don't want to spray before the MAF as it would most likely damage the sensor.
Perhaps rather than trying to cover up the option by cooling down the charge you should be looking for a root cause as to why the sensor is seeing high IAT's in the first place.
Originally Posted by athenG
It don't matter since the IAT Sensor is in the MAF Sensor. Unless you go Standalone then there is not much way of getting around this since the ECU is in control with just a flash. Just bite the bullet and get a Utec if cash is limited since on boost Utec don't really care if the IAT is too high. The ECU wont bark with Utec since your IAT won't go up when you are not on boost anyways..
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Originally Posted by taurran
Perhaps rather than trying to cover up the option by cooling down the charge you should be looking for a root cause as to why the sensor is seeing high IAT's in the first place.
Originally Posted by rcdash
What is the IAT? What is the specific code? Do you have Cipher? Post a snapshot of a run logging IAT if you can. I think your IAT is not reading correctly.
Originally Posted by rcdash
What is the IAT? What is the specific code? Do you have Cipher? Post a snapshot of a run logging IAT if you can. I think your IAT is not reading correctly.
Originally Posted by 350 Rookie
Well i have a utec, but im waiting for another couple of weeks before i go for a tune at MRC. So with utec, this problem will be eliminated or will i still go into limp mode?
Once you are on boost then the ECU is not much in control with Utec but if your IAT sensor is damaged or not reading correctly then your Temp Compensation in Utec will be way off so you may want to get that fix first. Like taurran said @ 8psi then you should not have any problem unless you have been driving real hard for hours in the middle of 90+F heat then it is possible that you getting heat soaked.. You should be able to log IAT with utec (with the help of the UTI Software), so that is another nice thing so you can see how efficient your cooling is.
http://www.uprev.com/products/cipher_NI.html
Just do the UTEC logging if it can record IAT (as AthenG suggests).
Just do the UTEC logging if it can record IAT (as AthenG suggests).
Originally Posted by rcdash
http://www.uprev.com/products/cipher_NI.html
Just do the UTEC logging if it can record IAT (as AthenG suggests).
Just do the UTEC logging if it can record IAT (as AthenG suggests).
+1 Cipher is another great tool but that is extra $400. Just hurry up and go to MRC and install the Utec, if there is any other problem then Julian should be able to point it out to you... You need the UTI software to be able to log IAT and Coolant Temp. You need to go to http://jeffsoftware.com/ and it cost $25. UTI has other nice feature like Autologging, Sound Feedback..etc. So it is worth getting IMHO.
Here's a sample of the logs UTI give you.. Intake Air temp is 3rd to the last column and Coolant Temp is 2nd to the last..
Code:
[TSMP][RPM][PSIG][MAF][TPS][LOD][KN][SIG][IDC%][IGN][VOEF][BMV][MMV][WBO2][AIT][CLT][IGNT] 691.72 3008 -8.9 1.9 2 0 0 33.1 7.8 ECU 100 000 1.9 12.61 029 082 1.834 691.91 3027 -10.4 2.0 1 0 0 34.3 5.3 ECU 100 000 1.8 14.23 029 082 1.889 692.12 3016 -9.9 2.3 25 0 0 42.2 9.3 ECU 100 000 2.8 14.83 029 082 2.332 692.32 3027 -3.3 3.2 34 0 0 27.3 7.8 ECU 100 000 2.6 13.20 030 083 1.503 692.52 3333 -9.1 2.1 2 0 0 34.1 8.4 ECU 100 000 2.0 12.70 030 083 1.705 692.72 3603 -10.5 2.0 1 0 0 32.1 6.0 ECU 100 000 3.1 13.65 030 083 1.485 692.92 3858 -9.7 1.9 1 0 0 34.1 8.1 ECU 100 000 2.1 13.59 029 081 1.473 693.12 3987 -9.5 2.1 1 0 0 34.1 8.4 ECU 100 000 2.9 12.93 029 082 1.425 693.32 4030 -2.8 3.6 92 0 0 24.0 38.0 ECU 100 000 3.5 12.74 029 082 0.993 693.52 4041 -1.2 3.7 99 10 0 22.0 29.2 ECU 100 000 3.6 11.96 029 081 0.907 693.72 4067 -0.1 3.8 100 10 0 30.1 34.9 21.0 +2.0 000 3.7 11.62 031 082 1.234 000.00 4096 +1.0 4.0 100 10 0 29.2 35.7 20.4 +2.0 000 3.8 11.81 030 081 1.188 000.20 4170 +2.1 4.2 98 30 0 24.0 43.1 19.2 +2.0 000 3.9 11.69 031 082 0.959 000.40 4261 +3.4 4.3 100 40 0 27.1 49.5 17.7 +2.0 000 4.1 11.48 030 081 1.060 000.61 4360 +5.0 4.4 98 60 0 25.2 55.6 16.0 100 000 4.2 11.24 032 081 0.963 000.80 4458 +6.6 4.6 100 70 0 24.9 66.0 13.0 +2.0 000 4.3 11.20 032 081 0.931 001.00 4558 +7.8 4.7 99 80 0 24.9 72.4 13.0 100 000 4.4 11.39 033 081 0.910 001.20 4680 +8.2 4.9 100 80 0 23.0 76.5 12.4 100 000 4.6 11.52 033 081 0.819 001.40 4790 +8.2 4.9 100 80 0 22.9 79.4 12.7 100 000 4.5 11.49 034 081 0.797 001.60 4916 +7.8 5.0 100 80 0 24.1 80.6 13.3 100 000 4.6 11.37 034 081 0.817 001.83 5053 +7.6 5.0 99 80 0 23.1 81.6 13.7 100 000 4.5 11.30 035 081 0.762 002.00 5152 +7.6 5.0 100 80 0 22.0 84.0 14.3 100 000 4.6 11.28 035 081 0.712 002.20 5231 +7.5 5.0 98 80 0 19.4 85.0 14.4 100 000 4.6 11.34 037 082 0.618 002.40 5416 +7.3 5.0 100 80 0 20.9 86.2 14.7 100 000 4.6 11.43 035 081 0.643 002.60 5548 +7.3 5.0 99 80 0 20.7 86.4 14.5 100 000 4.6 11.45 038 082 0.622 002.80 5611 +7.5 5.0 100 80 0 21.0 87.5 15.0 100 000 4.6 11.48 039 082 0.624 003.00 5709 +7.5 5.0 98 80 0 22.0 87.9 15.4 100 000 4.6 11.72 038 082 0.642 003.20 5820 +7.5 5.0 44 10 0 21.9 88.8 18.4 100 000 2.5 11.98 038 082 0.627 003.39 5688 -9.6 3.0 1 0 0 34.0 9.5 ECU 100 000 1.7 11.98 038 082 0.996 003.60 5294 +2.4 4.6 100 30 0 17.1 40.7 18.0 100 000 4.2 11.65 040 083 0.538 003.81 4860 +4.4 4.5 100 50 0 22.9 59.5 15.5 100 000 4.3 11.20 039 082 0.785 004.02 4761 +6.8 4.5 100 80 0 19.2 68.2 13.0 100 000 4.5 11.19 040 083 0.672 004.21 4766 +8.6 4.9 100 90 0 21.0 77.5 11.0 100 000 4.5 11.37 041 083 0.734 004.41 4769 +9.1 4.9 100 90 0 22.9 80.7 10.9 100 000 4.6 11.42 041 083 0.800 004.59 4843 +8.8 4.9 100 90 0 22.9 81.5 11.8 100 000 4.6 11.27 041 083 0.788 004.80 4929 +8.2 4.9 100 80 0 23.0 80.9 12.4 100 000 4.5 11.06 041 083 0.778 004.99 4996 +8.0 5.0 100 80 0 23.0 81.6 12.9 100 000 4.6 10.99 041 083 0.767 005.20 5064 +7.9 4.9 100 80 0 23.0 82.6 13.2 100 000 4.6 11.02 043 084 0.757 005.40 5143 +7.9 5.0 100 80 0 22.0 83.6 13.7 -1.0 000 4.6 11.48 043 084 0.713 005.59 5167 -7.6 2.1 0 0 0 32.0 15.3 ECU 100 000 2.1 12.03 043 084 1.032 005.80 4803 -10.8 2.0 1 0 0 33.0 5.7 ECU 100 000 2.1 14.53 042 084 1.145 006.00 4403 -10.8 1.6 0 0 0 13.1 5.3 ECU 100 000 1.6 25.00 042 084 0.496 006.20 3963 -10.1 2.5 1 0 0 06.1 5.0 ECU 100 000 2.2 25.00 042 084 0.257 006.40 3595 -9.8 2.3 0 0 0 01.0 1.4 ECU 100 000 2.1 25.00 041 084 0.046 006.60 3233 -9.6 1.9 1 0 0 01.0 1.3 ECU 100 000 1.9 25.00 040 084 0.052
Last edited by athenG; Aug 12, 2008 at 12:06 PM.
Originally Posted by UMW350Z
How do you get out of limp mode once it goes into limp mode?
Had this problem a few times when my Meth Controller went bad... MAF Sensor was soaking wet so I had to dry it out and it was fine the next start. Restarting the car can help but if the problem is still there then you will always end up going to Limp Mode. I'm amazed the my MAF is still working after getting soaking wet 3 times.
What version are you using to log AIT?
Originally Posted by athenG
+1 Cipher is another great tool but that is extra $400. Just hurry up and go to MRC and install the Utec, if there is any other problem then Julian should be able to point it out to you... You need the UTI software to be able to log IAT and Coolant Temp. You need to go to http://jeffsoftware.com/ and it cost $25. UTI has other nice feature like Autologging, Sound Feedback..etc. So it is worth getting IMHO.
Here's a sample of the logs UTI give you.. Intake Air temp is 3rd to the last column and Coolant Temp is 2nd to the last..
Here's a sample of the logs UTI give you.. Intake Air temp is 3rd to the last column and Coolant Temp is 2nd to the last..
Code:
[TSMP][RPM][PSIG][MAF][TPS][LOD][KN][SIG][IDC%][IGN][VOEF][BMV][MMV][WBO2][AIT][CLT][IGNT] 691.72 3008 -8.9 1.9 2 0 0 33.1 7.8 ECU 100 000 1.9 12.61 029 082 1.834 691.91 3027 -10.4 2.0 1 0 0 34.3 5.3 ECU 100 000 1.8 14.23 029 082 1.889 692.12 3016 -9.9 2.3 25 0 0 42.2 9.3 ECU 100 000 2.8 14.83 029 082 2.332 692.32 3027 -3.3 3.2 34 0 0 27.3 7.8 ECU 100 000 2.6 13.20 030 083 1.503 692.52 3333 -9.1 2.1 2 0 0 34.1 8.4 ECU 100 000 2.0 12.70 030 083 1.705 692.72 3603 -10.5 2.0 1 0 0 32.1 6.0 ECU 100 000 3.1 13.65 030 083 1.485 692.92 3858 -9.7 1.9 1 0 0 34.1 8.1 ECU 100 000 2.1 13.59 029 081 1.473 693.12 3987 -9.5 2.1 1 0 0 34.1 8.4 ECU 100 000 2.9 12.93 029 082 1.425 693.32 4030 -2.8 3.6 92 0 0 24.0 38.0 ECU 100 000 3.5 12.74 029 082 0.993 693.52 4041 -1.2 3.7 99 10 0 22.0 29.2 ECU 100 000 3.6 11.96 029 081 0.907 693.72 4067 -0.1 3.8 100 10 0 30.1 34.9 21.0 +2.0 000 3.7 11.62 031 082 1.234 000.00 4096 +1.0 4.0 100 10 0 29.2 35.7 20.4 +2.0 000 3.8 11.81 030 081 1.188 000.20 4170 +2.1 4.2 98 30 0 24.0 43.1 19.2 +2.0 000 3.9 11.69 031 082 0.959 000.40 4261 +3.4 4.3 100 40 0 27.1 49.5 17.7 +2.0 000 4.1 11.48 030 081 1.060 000.61 4360 +5.0 4.4 98 60 0 25.2 55.6 16.0 100 000 4.2 11.24 032 081 0.963 000.80 4458 +6.6 4.6 100 70 0 24.9 66.0 13.0 +2.0 000 4.3 11.20 032 081 0.931 001.00 4558 +7.8 4.7 99 80 0 24.9 72.4 13.0 100 000 4.4 11.39 033 081 0.910 001.20 4680 +8.2 4.9 100 80 0 23.0 76.5 12.4 100 000 4.6 11.52 033 081 0.819 001.40 4790 +8.2 4.9 100 80 0 22.9 79.4 12.7 100 000 4.5 11.49 034 081 0.797 001.60 4916 +7.8 5.0 100 80 0 24.1 80.6 13.3 100 000 4.6 11.37 034 081 0.817 001.83 5053 +7.6 5.0 99 80 0 23.1 81.6 13.7 100 000 4.5 11.30 035 081 0.762 002.00 5152 +7.6 5.0 100 80 0 22.0 84.0 14.3 100 000 4.6 11.28 035 081 0.712 002.20 5231 +7.5 5.0 98 80 0 19.4 85.0 14.4 100 000 4.6 11.34 037 082 0.618 002.40 5416 +7.3 5.0 100 80 0 20.9 86.2 14.7 100 000 4.6 11.43 035 081 0.643 002.60 5548 +7.3 5.0 99 80 0 20.7 86.4 14.5 100 000 4.6 11.45 038 082 0.622 002.80 5611 +7.5 5.0 100 80 0 21.0 87.5 15.0 100 000 4.6 11.48 039 082 0.624 003.00 5709 +7.5 5.0 98 80 0 22.0 87.9 15.4 100 000 4.6 11.72 038 082 0.642 003.20 5820 +7.5 5.0 44 10 0 21.9 88.8 18.4 100 000 2.5 11.98 038 082 0.627 003.39 5688 -9.6 3.0 1 0 0 34.0 9.5 ECU 100 000 1.7 11.98 038 082 0.996 003.60 5294 +2.4 4.6 100 30 0 17.1 40.7 18.0 100 000 4.2 11.65 040 083 0.538 003.81 4860 +4.4 4.5 100 50 0 22.9 59.5 15.5 100 000 4.3 11.20 039 082 0.785 004.02 4761 +6.8 4.5 100 80 0 19.2 68.2 13.0 100 000 4.5 11.19 040 083 0.672 004.21 4766 +8.6 4.9 100 90 0 21.0 77.5 11.0 100 000 4.5 11.37 041 083 0.734 004.41 4769 +9.1 4.9 100 90 0 22.9 80.7 10.9 100 000 4.6 11.42 041 083 0.800 004.59 4843 +8.8 4.9 100 90 0 22.9 81.5 11.8 100 000 4.6 11.27 041 083 0.788 004.80 4929 +8.2 4.9 100 80 0 23.0 80.9 12.4 100 000 4.5 11.06 041 083 0.778 004.99 4996 +8.0 5.0 100 80 0 23.0 81.6 12.9 100 000 4.6 10.99 041 083 0.767 005.20 5064 +7.9 4.9 100 80 0 23.0 82.6 13.2 100 000 4.6 11.02 043 084 0.757 005.40 5143 +7.9 5.0 100 80 0 22.0 83.6 13.7 -1.0 000 4.6 11.48 043 084 0.713 005.59 5167 -7.6 2.1 0 0 0 32.0 15.3 ECU 100 000 2.1 12.03 043 084 1.032 005.80 4803 -10.8 2.0 1 0 0 33.0 5.7 ECU 100 000 2.1 14.53 042 084 1.145 006.00 4403 -10.8 1.6 0 0 0 13.1 5.3 ECU 100 000 1.6 25.00 042 084 0.496 006.20 3963 -10.1 2.5 1 0 0 06.1 5.0 ECU 100 000 2.2 25.00 042 084 0.257 006.40 3595 -9.8 2.3 0 0 0 01.0 1.4 ECU 100 000 2.1 25.00 041 084 0.046 006.60 3233 -9.6 1.9 1 0 0 01.0 1.3 ECU 100 000 1.9 25.00 040 084 0.052
Originally Posted by str8dum1
What version are you using to log AIT?
I have Ver. 2.7.5. So far the only time I know 2.7.5 work is if you have the Tuner, else Dashboard mode wont work with just the Utec. You need to be in Dashboard mode to log the AIT and Coolant Temp. If you don't have the Tuner then you need 3.x version but that still have some bugs to be ironed out.