Disregard my post. Had the EGR out today and it was indeed caked with carbon. Blasted it with brake cleaner and gave it a proper scrub, and there has been a noticeable improvement. Much less smoke and soot on a limiter bounce. However, while the valve was out of the way I noticed a 6" split in the hose between the intercooler and EGR, which is have replaced my map sensor, no different, ford did tell me the MAP and MAF sensors were fine, having searched the internet, a possiblity is the EGR valve having become sticky, have had the RAC inspect the car, came up with fault code p0069, like you say split in hose or air getting in causing an overboost but not found any such thing yet My engine warning light (MIL) has come on permanently and using Forscan diagnostics am told the EGR valve is stuck open. The car is a 2009 Focus 1.6 Tdci with 55k miles. I intend to remove the EGR valve, clean it with oven cleaner, and put it back with a blanking plate. My focus was losing power when up to temperature and I got the following error codes using Forscan: P1412-60 - EGR valve frozen P0490-20 - EGR Circuit high P042F-40 - EGR Stuck closed P042F-C - EGR stuck closed So, I brought it to the garage and they fitted a new EGR valve - Haas I believe. Driving normally on a standard day - Engine Malfunction came up on the dash. I have a code reader which showed (P0069 - Manifold Absolute Pressure/Barometric Pressure Correlation). I cleared the code, took it for a drive and same thing occurred. Read on-line that the issue could be with: 1)Manifold Pressure Sensor or associated wiring. Ford Model: 1.8 TDCI Mk2 Focus Ford Year: 2006 UK/Ireland Location: Dorset EGR problems did not put my car into limp mode, but did light the warning light. But it So i fitted a blanking EGR plate to my 09 Focus 1.6tdci 109bhp with 65,000 miles and the engine light came on showing (P042F Blocked or stuck EGR Valve) and the car lost power so i removed the plate and bought a D900 OBD reader to reset the codes. The engine light came on again after 3 or 4 miles so i removed the egr valve, and cleaned with Thu 14 Oct 2010 00:21. Ford focus tdci - coolant pressurisation - Railroad. You should not remove a two-stage thermostat. It's purpose is to allow coolant to run round a by-pass when the thermostat is closed. This ensures even cooling and prevents hotspots forming. When the thermostat opens the by-pass is closed off. cDBGmD.