I'm posting this in the 7M section as my 2J is still running 7MGTE electronics.
I have also looked through 20 pages of threads while searching for this issue ................... since 4:15am.
Specs on the setup:
2JZ GE-T using JDM 7MGTE electronics and harness
MAFT Pro
factory 7MGTE 440's and CT26
Onto the issue:
Car will not start when the ambient temp is below 70*-75*
No start condition is failure of spark. The only code I am recieving is code 12 - Loss of NE or G to ECU
For the past 3-5 days, when I go to leave for work at 5:15a, the car will not start due to above. When I get home (temps between 85* and 100*) the car fires right up with no issue at all. I spent several hours last night working with the car and trying to diagnose the issue. I do not have an oscilliscope, so I have no good way of verifying the actual signals being sent from the CPS.
Last night while working with it, I ohmed out the CPS and found I had infinite resistance between G2 and G- Spec calls for 140-180 ohms
I replaced the CPS and retimed the car. During the my time working with it last night, the car never once failed to start. I have performed continuity tests on all wiring for ECU, igniter, and coils. All wires are showing continuity, the CPS wires are (on all 4) showing a resistance value of about .6-.7 ohms from plug at CPS to ECU plug.
I left the car last night in a fully running condition - the only complaint I have when it does run, it will develop a misfire after reaching operating temperature. Not a huge misfire, but noticiable.
Believing that temperature has something, if not everything, to do with the issue; I even went as far as "icing down" the igniter,CPS,and coil pack last night. This did not cause a nostart condition. I also verified correct operation of coolant temperature sensor; resistance reading was within spec listed in TSRM.
When going out to start the car up this morning, I initially tried to start it and the tach wouldn't budge while cranking. After a few tries later, I saw the tach bounce just a bit and heard the engine attemp to fire. That lasted only a short second or two. Since then, no tach movement, and no start. I have replaced the igniter many times (I have a few of these floating around) and did it again this morning out of desperation. I also swapped the ECU with another known working unit from my old 7M - no change at all.
I am truly at my wits end with this car. I've only put about 350 miles on the car since the swap was completed. BTW - this no start issue has reared up in the past. Since the last 7M i was running. It was a JDM motorset, harness, ECU from an importer in Jersey. When that motor was running, the car did this exact thing to me only one time. It actually stalled out and wouldn't restart for over 30 minutes when it happened. That was well over a year ago, and until the JZ was put in I didn't have the issue at all. Now that the JZ is in, this has become a frequent problem. I am at the point where due to scheduling, I can no longer take my wife's car to work, and can't afford to be fired for not going to work....
Solution:
Replaced entire wire from CPS to ECU. Used exact wire from spare harness and properly repinned into current harness.
Lesson learned.... even though the wiring in the car showed good continuity, it was still bad...
Thank you Supramania.
I have also looked through 20 pages of threads while searching for this issue ................... since 4:15am.
Specs on the setup:
2JZ GE-T using JDM 7MGTE electronics and harness
MAFT Pro
factory 7MGTE 440's and CT26
Onto the issue:
Car will not start when the ambient temp is below 70*-75*
No start condition is failure of spark. The only code I am recieving is code 12 - Loss of NE or G to ECU
For the past 3-5 days, when I go to leave for work at 5:15a, the car will not start due to above. When I get home (temps between 85* and 100*) the car fires right up with no issue at all. I spent several hours last night working with the car and trying to diagnose the issue. I do not have an oscilliscope, so I have no good way of verifying the actual signals being sent from the CPS.
Last night while working with it, I ohmed out the CPS and found I had infinite resistance between G2 and G- Spec calls for 140-180 ohms
I replaced the CPS and retimed the car. During the my time working with it last night, the car never once failed to start. I have performed continuity tests on all wiring for ECU, igniter, and coils. All wires are showing continuity, the CPS wires are (on all 4) showing a resistance value of about .6-.7 ohms from plug at CPS to ECU plug.
I left the car last night in a fully running condition - the only complaint I have when it does run, it will develop a misfire after reaching operating temperature. Not a huge misfire, but noticiable.
Believing that temperature has something, if not everything, to do with the issue; I even went as far as "icing down" the igniter,CPS,and coil pack last night. This did not cause a nostart condition. I also verified correct operation of coolant temperature sensor; resistance reading was within spec listed in TSRM.
When going out to start the car up this morning, I initially tried to start it and the tach wouldn't budge while cranking. After a few tries later, I saw the tach bounce just a bit and heard the engine attemp to fire. That lasted only a short second or two. Since then, no tach movement, and no start. I have replaced the igniter many times (I have a few of these floating around) and did it again this morning out of desperation. I also swapped the ECU with another known working unit from my old 7M - no change at all.
I am truly at my wits end with this car. I've only put about 350 miles on the car since the swap was completed. BTW - this no start issue has reared up in the past. Since the last 7M i was running. It was a JDM motorset, harness, ECU from an importer in Jersey. When that motor was running, the car did this exact thing to me only one time. It actually stalled out and wouldn't restart for over 30 minutes when it happened. That was well over a year ago, and until the JZ was put in I didn't have the issue at all. Now that the JZ is in, this has become a frequent problem. I am at the point where due to scheduling, I can no longer take my wife's car to work, and can't afford to be fired for not going to work....
Solution:
Replaced entire wire from CPS to ECU. Used exact wire from spare harness and properly repinned into current harness.
Lesson learned.... even though the wiring in the car showed good continuity, it was still bad...
Thank you Supramania.
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