We have a rigmaster on our truck and it never idled down after starting. It always ran at one continuous speed. I think that is how they are supposed to run. The only time I heard a change is when the a/c compressor would kick on, but other than that it was the same. We have had some problems with ours like the alternator pivot bolt broke and ended up drilling out the hole and putting a bolt all the way through with a nut and washer. It seems to loose prime in the fuel system once in a while and don't know why. (I've become an expert on priming the fuel system). I had one instance where the fuel shut off lever had popped out of the petcock, I took it out and noticed it had bent in the channel where the set screw rides. So I took a hammer and very carefully tapped it straight and viola!, it has not failed again. Still don't know why it happened but all I can come up with is that for some reason it may have built up to much pressure in the fuel system?. If you have speedco service it make sure they prime the fuel system after the fuel filter is replaced. What we do is pull it outside and run it for at least 5 mins. before we leave, usually while I'm inside taking care of the bill, that way you know it is primed properly. Hope this helps you out.