Have a 2002 SeaDoo GTX, NON Supercharger, first year for the FI 4-Tech. Just serviced it, oil and filter and NGK spark plugs. The idle fluctuates 2500 RPMs to 3500 RPMs. Up and down as it is running on the hose. I've read that it could be a coil, TPS, TB air leak. Could it be anything else? Is there a way to narrow it down to find out what the cause is? Appreciate any info.thanks