so I'm still working on this engine miss I'm getting. Only noticeable at idol, it comes and goes. The RPMs will rise and lower from 600 to 900. its not a fast change. and not consistent. At times it will not do it. So, I changed the plugs, changed air filter, checked MAF for blockage, checked for vacuum leaks, I've got a fuel filter and plug wires on order. Today i read the codes and well there was a lot, but they've probably never ever been cleared, and I did have a few comm issues that I've recently fixed so I wrote all the codes down and then cleared them. And then started the engine let idol for a bit, revved a bit. (didn't test drive becuase it was raining) and then I checked the codes. The only code I get (and it was showing previous to clearing the codes) is the code 10-PCM P1652 H C.

So I Think I understand whats going on here, ESC module is commanded by the PCM to force all four shock absorber solenoids to a firm position during braking and hard acceleration. This command is completed by a driver in the PCM which pulls down to 0V and its not doing it's job. Here, read this info I found:

From the service manual:

Circuit Description

The powertrain control module (PCM) controls the powertrain induced chassis pitch by grounding the control circuit via an internal switch called a driver. The primary function of the driver is to supply the ground for the controlled component. The driver has a fault line which is monitored by the PCM. When the PCM commands a component ON, the voltage of the control circuit should be low, near 0 volts. When the PCM commands the control circuit to a component OFF, the voltage potential should be a high 5 volts (4.5-5.5 volts). If the fault detection circuit senses a voltage other than what the system expects, the fault line status changes causing the DTC to set.

The PCM receives an 5 volt (4.5-5.5 volts) reference signal from the electronic suspension control (ESC) module on the powertrain induced chassis pitch circuit. The PCM grounds this circuit when the vehicle accelerates rapidly or brakes hard. When the chassis pitch input circuit goes low to about 0 volts, the ESC module commands all four shock absorber solenoids to a firm position. The PCM calculates the chassis pitch information based on the engine torque and the vehicle braking force.


Conditions for Running the DTC

1. Engine speed greater than 400 RPM.
2. The system voltage is greater than 6 volts but less than 18 volts.


Conditions for Setting the DTC

1. The PCM detects that the commanded state of the driver and the actual state of the control circuit do not match.
2. The condition must exist for a minimum of 5.0 seconds.

 

So my question is this, How can I fix this, and what would I experience if I leave this? (there is not a check engine light). If I need to replace the PCM I imagine that would be a big hit. possibly for nothing I would notice during driving.

I don't suppose there's any corelation between this code and my engine miss?

 

Whatever it is, it keeps coming back immediately after I clear it. But nothing is operating out of the ordinary.