My truck is producing two suspension fault codes, 2010 Range Rover with 105k miles.

C1A18-64 (AF) Pressure increases too rapid when filling reservoir - Algorithm based failure - signal plausibility failure

C1130-66 (2C) Air spring air supply - Algorithm based failure - signal has too many transition/events

It has been producing the C1130-66 (2C) code on and off for about a month, usually doesn't come back for a week or two at a time, Ive been trying to track the leak. But this new code comes back immediately after clearing with the IID, its been fairly cold here in Chicago being in the single digits and tonight dropping to -8 degree F. The truck does lower and raise but when raising it raises very slowly. Im thinking this is a front valve block failure any other thoughts?

Getting to the route cause of a suspension fault can be a real pain. There is lots of good advice out there and I am by no means an expert but I had slow rising on my car. A compressor rebuild kit from 4x4 air seals has the suspension rising up far quicker so I can heartily recommend it. I’ve done the same on a mates car and it’s had the same effect. Job took 2 hours from start to finish. As for the rest of the symptoms three other mates are having similar issues and were going through each of the valve blocks, single one attached to the compressor and the triple ones front and back.

My overall felling is very much worth getting the compressor rebuild kit AND the full valve block kit and going through all of it one by one. All jobs are very doable plus I’ve found unbelievable gunk in the compressor that is probably down stream and preventing valves opening/closing/fully sealing.

Once you have all seals done throughout the whole car if you do get a dropped car as least you won’t be thinking valve or bag. Current
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Could be your rear valve block not operating correctly. Do a web search on the first fault code and you'll get quite a few hits / suggestions to try.

Theory being the rear valve block doesn't open to fill the reservoir so the pressure builds too rapidly. 2016 Skoda Octavia VRS Estate
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