No noticeable difference in smoke. But when it's starting to warm up it does smell a little bit fuely. With regards to the maf disconnected , why would it get worse and stall several times?? Took it for a quick run to the local garden centre and stalled out 7 times when I had to stop / slow down. As cutting out when it dropped to idle , unless you caught it in time. I've ordered both usb and Bluetooth as they're only £6 /£7 ea