Question: I own a 1996 Silver Spirit MkIV VIN No. SCAZS12C6TCH57948. I have owned this car for about a year now & it has always had what I thought was a slight miss at around 50mph. After I purchased it I gave it a service & changed the plugs, all oils & filters including the gearbox. this did not cure the problem so I gave the car to a local Rolls Royce specialist for investigation. He plugged a diagnostic device into the car & drove it some 30 miles to his workshop (he did not notice the "miss" at first as it is only slight). Upon arrival at his workshop he downloaded the info from the diagnostic kit to his computer but this showed no faults (he did say that fault codes on the Silver Spirit are limited). He checked out the plug leads & coils which were OK so he changed the engine ECU for the one on his MkIII Spirit but this made no difference. He then came to the conclusion that it was not the engine but the gearbox that was the problem & the "miss" was in fact the TCC engaging & dis engaging at around 50mph. This seems to be confirmed by the fact that if the car is run in 3 instead of drive the problem does not occur. I was wondering if this is a common problem on this model or is the transmission ECU over sensitive causing the clutch to engage & disengage within a very narrow speed range. Any advice on this matter would be greatly appreciated.
Answer: It might be worth changing the 2 front phonic wheels (part number UR26955) and then clear the fault codes. Failing that all I can suggest is to try a different gearbox ecu and see if that can correct the problem.
Question: It has taken me some time but I have finally managed to get the gearbox on my car sorted. I took it to a local auto gearbox specialist in Darlington (S. Blackett & Son) who went out for a test drive & agreed there was a problem with the gearbox. He removed the gearbox whereupon he found the torque convertor was beyond repair (the torque convertor is a sealed unit however Steve knows a firm who can separate the unit & normally repair it). After replacing the unit the problem is now sorted.