Reduced engine power.
But I notice it happens more right when I turn on the A/C.
But I notice it happens more right when I turn on the A/C.
Sep 15, 2023 at 10:38 AM
codes Po1516 and po1518?
2003 CHEVROLET SUBURBAN
DARLYNS CAKES
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Hi,
This can be caused by a couple of things. For example, if you have a weak battery, it can set this code.
On the other hand, it can be related to the throttle actuator control system (TAC). The DTC P1518 can be set if the TAC module ignition feed circuit is shorted to a B+ supply circuit. The TAC module stays powered up when the ignition switch is turned OFF. When the ignition switch is turned ON, the TAC module is powered up before the PCM. As a result, DTC P1518 sets because no communication is detected by the TAC module from the PCM. We need to Inspect related circuits for being shorted to a B+ supply circuit.
Take a look below. I attached diagnostics related to the code. Although there are a few things covered, to me it seems related to what I mentioned above because the P1516 is related to the throttle position actuator. The throttle position (TP), is based on the accelerator pedal position (APP) and is compared to the actual throttle position. The two values should be within a calibrated range of each other. In this case, I suspect the short is causing the two to be out of range of each other.
Take a look at the attached pics. They are the diagnostics. Let me know if this is something you are comfortable performing.
Take care,
Joe
See pics below.
This can be caused by a couple of things. For example, if you have a weak battery, it can set this code.
On the other hand, it can be related to the throttle actuator control system (TAC). The DTC P1518 can be set if the TAC module ignition feed circuit is shorted to a B+ supply circuit. The TAC module stays powered up when the ignition switch is turned OFF. When the ignition switch is turned ON, the TAC module is powered up before the PCM. As a result, DTC P1518 sets because no communication is detected by the TAC module from the PCM. We need to Inspect related circuits for being shorted to a B+ supply circuit.
Take a look below. I attached diagnostics related to the code. Although there are a few things covered, to me it seems related to what I mentioned above because the P1516 is related to the throttle position actuator. The throttle position (TP), is based on the accelerator pedal position (APP) and is compared to the actual throttle position. The two values should be within a calibrated range of each other. In this case, I suspect the short is causing the two to be out of range of each other.
Take a look at the attached pics. They are the diagnostics. Let me know if this is something you are comfortable performing.
Take care,
Joe
See pics below.
Images (Click to enlarge)
Sep 15, 2023 at 9:17 PM
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It's a 2003 Chevrolet suburban 5.3, but I have never had this problem with this truck until I had my rear main seal fixed and my battery was unhooked for 3 weeks.
Sep 16, 2023 at 6:02 AM
Hi,
If the rear main engine oil seal was replaced, they had the transmission removed. There is a chance that something happened that is causing a short. A wire may have been pinched or damaged.
Let me know.
Joe
If the rear main engine oil seal was replaced, they had the transmission removed. There is a chance that something happened that is causing a short. A wire may have been pinched or damaged.
Let me know.
Joe
Sep 16, 2023 at 9:41 PM