Hi, My wife and I bought a used LR D4 at the end on January - diesel, manual and about 83,000 miles. 3/4 weeks ago the Restricted Performance light came on. We have taken it to the local LR dealership and who thought it could be related to the fuel filter or moisture in the fuse box as a seal had broken, both where fixed. circa 350 miles later it happened again. This time the dealership have replaced the "fuel rail pressure", but it has happened again. One question the LR garage keep asking is has the car ever been misfuelled? - Not in our ownership of the last 9 months or so and hitherto we have had 5,000 miles or so of completely untroubled motoring - never misfired our even the suggestion of such. The six month RAC warranty we had when we acquired it has expired, but that aside we find it baffling that the LR garage keep suggesting it has been misfuelled given its performance over the last 9 months. We dread to think of what the cost might be to replace any parts owing to misfuelling - one hears of horror stories! and we would expect this will be unnecessary cost in any event. Is there anything else you could expect to be - the RAC man who towed me in suggested the ERG valves or the turbo pipes - but the engine does not make any bad sounds etc. We look forward to hearing from you. EMCS Newbury (25 September 2015)