Chasing problems?

[pikewrench]

While on a trip, at a little over 1k from home after stopping for the night, we went out to get a bite to eat and the check engine light came on while turning into a restaurant (Happened in Rice Lake WI). The coil for glow plugs flashed on also. Went back to the room and pulled the laptop out and my VCDS and read codes for low pressure fuel and sensor failure Talked with a friend at the dealer service and said it sounded like a catastrophic failure of the high pressure pump (common problem for this engine I was told) with the two codes i gave him and the flashing coil light. Vehicle still ran, but rpm was limited by the computer. I rented a uhaul truck and dolly and finished my trip and then home. Ordered parts online trying to make sure I had them when I got home, figuring that I would need to inspect the tank and ordered a new low pressure pump, high pressure pump, pressure sensor and pressure regulator for the fuel rail. While on the road pulled the pressure regulator off the HP pump and found no metal. Pulled the HP pump off and tore it down when i got home and found that the cup/piston that operates the plunger was showing wear on one side of the cylinder walls and the end of the stroke (got lucky). Replaced all the parts and got it back together and cleared all the codes and primed the system with the VCDS. Started the car. Check engine light came back on ( 2 faults On EGR). Cleared codes and ran it and codes came back for EGR valve failure-4 faults (4881) P1440-open circuit, (4900) P0405-Signal to low, (4891) P0403-Malfunction and a second (4892) P0403-malfunction. Cleared system and ran a separate EGR test thru VCDS and it came back as a malfunction. I guess the question now is after having fuel system problems is this really a sudden EGR failure or a problem with the ECM. This is on a 2013 Passat SE TDI with 125k miles. Both pressure regulators were tested for operation and both clicked open and closed. Car runs with limited rpms.

 

[pikewrench]

I printed out the VCDS reports that I had saved and noticed that my less than 4 year old battery was showing 11.7 volts and remembered the problems with codes it created last time. Replaced the battery and lost 3 of the 4 codes that VCDS had read. Still had a P1440 code. Ordered a new valve after reading what some had found and two sensors. While I had the cooler/throttle/EGR valve off I was finally able to locate the thermostat housing. Though it took some doing, I replaced the thermostat and housing that I had previously purchased. I found the triple square Allen separates from the socket base and used an 8mm wrench to turn and break the two bolts loose. Used a 30 torx to slowly remove the loosen bolt which is loose enough to be angled in. Loosen a couple hose brackets and the housing comes out with only the cable and plug in removed from the back of the alternator. Found that my EGR system had a light coating of carbon after 125k. Put the new egr valve in, but will keep the old. My 13 is back on the road.
On a side note I have found that marking the timing belt and pulleys with a paint stick/marker ensures success when putting the belt back or replacing after transferring the marks onto the new belt and yes I have the locking pins but still marked the belt because of the belt length that getting one tooth off is very easily done especially on the high pressure fuel pump.

 

[pikewrench]

Prior to this event in Rice Lake, I had noticed a drop in my fuel mileage and commented to my buddy on the last fueling that I was only averaging just over 39 mpg(should have been 42-44). I had also before that noticed a trend on my mileage decreasing from what I had been getting. As you can see in my picture on the left is the internal shot of the high pressure pump where the cup apparently had a bit of a slap on one side of the cylinder wall at the end of its travel. I apparently had a drop in fuel pressure being injected into the cylinder either caused by the wear in the wall or the high pressure regulator on the fuel rail. The valve did actuate when power was applied, but I don’t know if it was delivering the required pressure for mileage. Something to keep in mind if you are seeing a decrease in your mpg. And yes my mileage has definitely improved since I made the repairs.