S-type 2.7D 2004 EGR Help Please
 

Hello All

This is my first forum post, where hopefully I will be able to return some input to others in the future.

I have an issue that I require some help with, and something that may well help others in the future. This problem started on a hot afternoon trip of about 17 miles. Most of it motorway and about 3 miles country lanes. As soon as I left the motorway and de-accelerated the car went into a restricted or limp mode. I am not really sure which as no message came up and no MIL light. I am also not sure what the difference is, if there is a difference.

These are the codes that I read from the vehicle.

P0046-00 Turbo/supercharger boost control solenoid - circuit range/performance. Intermittent
P140A-00 Exhaust gas recirculation sensor C - circuit low. Intermittent
P004B-00 Turbo/supercharger boost control solenoid B - circuit range/performance. Temporary
P0405-00 Exhaust gas recirculation sensor A - circuit low. Intermittent
P010F-00 Mass or volume air flow sensor A/B correlation. Intermittent

I cleared the faults down and the following day, not on the way to work, but on the way back the same happened again, when it was noticeably warmer than my morning trip.

To cut a long story short, having read the forums I started looking at the EGR valves and monitoring the data from them on another trip to work. This showed one of the valves positions not moving relative to it's command signal.

As far a I can gather the EGR's goes through a cleaning cycle when the vehicle is switched off. The drivers side (Right hand drive) EGR could be heard cycling, but the passenger side EGR could not be heard cycling.

To try and fault find this I decided to compare the working one with the faulty one. The electrical drawings that I have do not seem to help much as it appears they do not include drawings for the 2.7D engine, and do not show both EGR valves. If someone could help with this I would appreciate it. When monitoring the voltages on the working EGR, the only real value I could pick up was on the central wire of the five on the EGR plug. The cable is green in colour. This rose in voltage as the valve opened and the voltage went up and down when going through it's cleaning cycle. The faulty valve did not show any voltage on it of any significance.

I did look at the pinpoint test B in the manual, but can't be certain that it is the right information for my model. Some of it did not make sense which a reliable wiring diagram would help to verify what is being tested.

So hopefully you have not fallen asleep reading this, and if anyone could help with a reliable diagram for this and maybe some advise on the best way to fault find this issue, and what readings should be on the EGR terminals. I do not really want to replace the EGR valve if not required as it could be a wiring fault or another component, and the suspect EGR looks like a bit of a pain to get to.

Thanks for any help. Cheers Laurie