2 weeks ago pulled a P0401 Insufficent EGR Flow. cleaned EGR valve, replaced EGR vacuum solenoid, replaced DPFE, replaced EGR valve sensor, replaced PCV, checked all elbows and hoses for leaks - all good. Finally I pulled the upper and lower manifold to reveal 4 of 6 EGR ports blocked with carbon buildup. Soaked intake manifold overnight. Used brushes and pipe cleaners to clean every orifice I could find. Reassembled with a new gasket kit. Drove vehicle for 15 minutes NO problem and no problem codes. However, I notived the engine did not register on the temperature gauge. I had forgot to hook up electrical connector. Hooked it up and got error codes P0340 (camshaft position sensor Bank 1 circuit malfunction) and P1401 ( manufacturer controlled auxillary emission control). So I went for the 1st code and replaced camshaft sensor. No change. Having replaced the camshaft sensor and synchro 2 years previous; I made sure the camshaft was set at 54 degrees (with the special tool needed) while at TDC. All wiring appears in good shape. Cleared codes unhooked alternator to see if faulty diode was causing a problem. No dice. Checked for voltage KOEO at camshaft sensor and at crankshaft sensor. Red wire was battery voltage, green wire was .22V, black/white wire was ground. So it appears I have a circuit to camshaft sensor. I don't know where to go to next. New PCM? anything else I can check before I buy a new PCM?