Dandy. You have a 3.0L engine. I thought there was another V-6 available, but I see that is not the case for this model.
P0128 - ECT Below Thermostat Regulating Temperature
P0153 - Oxygen Sensor Circuit Slow Response (Bank 2 Sensor 1)
P0340 - Camshaft Position Sensor Circuit Malfunction
P0403 - Exhaust Gas Recirculation Circuit Malfunction
P0421 - Warm Up Catalyst Efficiency Below Threshold (Bank 1)
P0431 - Warm Up Catalyst Efficiency Below Threshold (Bank 2)
P0456 - EVAP Leak Monitor Small Leak Detected
Code 456 will usually require the use of a smoke machine because small leaks are almost impossible to find any other way.
Without digging further, code 403 is not specific enough to know where to start. This could refer to a failed sensor or its wiring for the sensor on the EGR valve. It could also refer to incorrect gas flow is seen when the valve is opened. Regardless, these two codes will not cause a no-start.
Codes 153, 421, and 431 could potentially all be related to code 128, so start with code 128. Suspect the thermostat is stuck open. If it is, you won't get nice hot air from the heater. The engine computer calculates fuel needs based on multiple engine sensors, including the engine coolant temperature, (code 128). When a specific temperature is reached, the system switches to "closed loop", meaning the computer adds the front oxygen sensors' readings to the list of variables to fine tune the fuel metering calculations. If the coolant is not getting up to normal operating temperature, the computer may not look at the O2 sensor readings. Codes 421 and 431 are derived from readings from the two rear oxygen sensors. The computer may be confused because what it expects to see is not taking place in the catalytic converters because they are not getting hot enough to do their thing.
The problem with my guessing is to set any diagnostic fault code, there is always a long list of conditions that must be met, and one of those conditions is certain other codes cannot already be set. That is because the computer is constantly comparing numerous sensor readings and operating conditions to each other to figure out when one is wrong. If a code is set for a sensor reading, any test that needs that reading to be compared to will be suspended. With some tests suspended, defects will not be detected and codes related to them will not be set. To say that a different way, when multiple codes are set, you must consider the possibility they all refer to individual, unrelated problems. The best approach is to start with anything that looks like it might be causing all the problems, fix that problem first, erase the fault codes, then see which codes set again, and start from scratch.
Code 340 is the one you need to start with. Listen for the hum of the fuel pump for one second after turning on the ignition switch. If you hear that, the automatic shutdown, (ASD), relay is working and the engine computer has control of it. That relay sends current to the ignition coil, injectors, oxygen sensor heaters, and fuel pump or pump relay. At issue is that relay turns on again during engine rotation, (cranking or running), and the computer knows that by the signal pulses it receives from the crankshaft position sensor and the camshaft position sensor. You have a code for the camshaft position sensor circuit, but a missing signal from either sensor will prevent the ASD relay from being turned on, and you will have no spark and no injector pulses.
By far most crank / no-starts are caused by loss of spark and fuel. Less than about five percent are caused by loss of spark or fuel. The fact you smell gas suggests you have only a loss of spark, but that would not agree with code 340. Assuming you do not have a scanner to view live data, the best approach is to replace the cam sensor. It is important to understand that fault codes never say to replace parts or that one is bad. When a part is referenced in a code, as in code 340 here, that part is actually the cause of that code about half of the time First we rule out wiring and connector terminal problems before we order a sensor, but in this case, the sensor costs a lot less than paying for an hour of diagnostic time. If you are wrong, you can save the part for later. If you are right, you will have saved a bundle.
Monday, December 26th, 2016 AT 2:38 PM