Tracking down p1121 and TB wiring
10-25-2016, 06:31 PM
#1
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Tracking down p1121 and TB wiring
Late 03 model AT5. Its actually a G35 but I really need some help/ideas, the G forums aren't that active anymore unfortunately. Been trying to track this issue down for 3 weeks now.
Problem - When car is turned off and than turned back on the car throws P1121, VDC, Slip lights. Car is then in fail safe limp mode (Won't rev past 2000k and barely accelerates)
What I've done to correct problem - Cleaned TB with TB cleaner and cleaned MAF with Maf cleaner. Made sure all hoses/vacuum lines are good, tight and no air leaks after the MAF. Performed ECU Reset both ways (battery disconnect overnight and the pedal/clock route. I've than done the accelerator, Throttle, and idle relearns. Everything takes like it should on the resets and relearns. When the car turns off and turns back on all the lights and code are back.
Today I finally decided to visually check wiring an connections at TB, Fuseable link, IPDM.
What I found at the IPDM and engine control harness has me thinking it may not be I need a new TB. Found 2 fuses that had burnt tips but the fuses weren't blown. The ECM and Throttle Body Actuator fuses in the IPDM, the 10 amp fuses I believe. Connections at the Throttle Body relay at the IPDM looked great also.
What I hear when the car turns off and key back on, is a bunch of clicks. I know you are supposed to hear 1 click for TPS or TB actuator but I hear about 3-4 fast clicks. Could these clicks be the TB actuator relay clicking off and on repeatedly and its a bad circuit with how the code only appears after I turn the car off and than back on.
If I keep the car on and clear the code and drive, whether its 10 minutes or 45 minutes of driving the code will not pop up. The car runs pretty good when the code is cleared.
Pics of the inside of the fuse location at the IPDM below. If you can see where it was burned.
I don't want to just throw a $100 TB in the car just to hope it fixes the problem if I don't know that's the issue. I will if I have too obviously. Its a pain in *** to let my car warm up, run the codes, clear the codes just to drive the car and do the same process again.
To add, the car started pulling timing at idle. Instead of a base 15 degrees of timing sometimes it drops to 2 degrees. A month ago my car never dropped less than 13 degrees of base timing at idle. Seems to level back out at part throttle or WOT. Fuel Trims on Short Term 1 and 2 are going past 9-11% on each bank. Long Term is usually around 4-8% on each bank. Fuel trims never go in the negative. Car coolant tips are around 183 to 195 steady. O2 Sensor voltage on all 4 usually sits at 0.1 volts at idle
Idle after relearn dropped to close to normal range about 750 RPM's but now back to 800-900 RPM's
So I'm exhausted at looking at this issue. Ive put countless hours into it checking this or checking that. I do not have a Multi-Meter however.
Thanks in advance
Problem - When car is turned off and than turned back on the car throws P1121, VDC, Slip lights. Car is then in fail safe limp mode (Won't rev past 2000k and barely accelerates)
What I've done to correct problem - Cleaned TB with TB cleaner and cleaned MAF with Maf cleaner. Made sure all hoses/vacuum lines are good, tight and no air leaks after the MAF. Performed ECU Reset both ways (battery disconnect overnight and the pedal/clock route. I've than done the accelerator, Throttle, and idle relearns. Everything takes like it should on the resets and relearns. When the car turns off and turns back on all the lights and code are back.
Today I finally decided to visually check wiring an connections at TB, Fuseable link, IPDM.
What I found at the IPDM and engine control harness has me thinking it may not be I need a new TB. Found 2 fuses that had burnt tips but the fuses weren't blown. The ECM and Throttle Body Actuator fuses in the IPDM, the 10 amp fuses I believe. Connections at the Throttle Body relay at the IPDM looked great also.
What I hear when the car turns off and key back on, is a bunch of clicks. I know you are supposed to hear 1 click for TPS or TB actuator but I hear about 3-4 fast clicks. Could these clicks be the TB actuator relay clicking off and on repeatedly and its a bad circuit with how the code only appears after I turn the car off and than back on.
If I keep the car on and clear the code and drive, whether its 10 minutes or 45 minutes of driving the code will not pop up. The car runs pretty good when the code is cleared.
Pics of the inside of the fuse location at the IPDM below. If you can see where it was burned.
I don't want to just throw a $100 TB in the car just to hope it fixes the problem if I don't know that's the issue. I will if I have too obviously. Its a pain in *** to let my car warm up, run the codes, clear the codes just to drive the car and do the same process again.
To add, the car started pulling timing at idle. Instead of a base 15 degrees of timing sometimes it drops to 2 degrees. A month ago my car never dropped less than 13 degrees of base timing at idle. Seems to level back out at part throttle or WOT. Fuel Trims on Short Term 1 and 2 are going past 9-11% on each bank. Long Term is usually around 4-8% on each bank. Fuel trims never go in the negative. Car coolant tips are around 183 to 195 steady. O2 Sensor voltage on all 4 usually sits at 0.1 volts at idle
Idle after relearn dropped to close to normal range about 750 RPM's but now back to 800-900 RPM's
So I'm exhausted at looking at this issue. Ive put countless hours into it checking this or checking that. I do not have a Multi-Meter however.
Thanks in advance
