Hello All, I picked up a '98 F355 F1 Berlinetta last month in British Columbia from the second owner for a fair price due to the fact that it was experiencing some F1 system issues. I have solved the issues and want to share my findings with you just in case it helps someone out of a similar situation. First off, this vehicle is running the Hill Engineering F360 F1 pump conversion kit that can be purchased through Ricambi America (part # PAB355F1-C). I know there is a bit of discussion about if these kits are good or not. It is what was on the vehicle when I purchased it so for the time being I'm going to be running this setup. Initially I couldn't even drive the vehicle. The F1 system kept erroring out when trying to grab any gears including reverse. Upon first examination I found that the daisy-chain of fittings coming out of the F360 pump were leaking on the suction side of the system so the F1 fluid reservoir had run dry. I pulled the pump, resealed the fittings, filled and bled the F1 system (without the scanner - more on this later), and checked again for leaks. All good! At this point I'm able to go into all forward and reverse gears reliably and there are no external fluid leaks. The next issue that I came across was that with the key on / engine off, the F1 pump would not stop cycling. It would prime, switch off, and prime again. This would continue as long as I had the key in the ON position. What I noticed was that there was an odd noise in between the run cycles of the F1 pump. It sounded like the pump was being forced in reverse. You can hear this in the video provided below. My theory at this point was that the high pressure side was pushing back to the low pressure side through the high pressure line due to a failed check valve somewhere in the system. I called Hill Engineering and spoke with Paul Hill about the kit. He informed me that his kit does have a check valve in it to prevent this from happening. After performing a few more tests I was able to confirm that the check valve had failed and a new one needed to be installed for the system to run correctly. After a little bit of trial and error I was able to develop a kit that incorporates a check valve externally into the Hill Engineering kit. Once installed and leak checked I was able to confirm that this fixed the problem. The video below was taken after the vehicle was sitting for two days with the new check valve kit installed. I’m very happy to see that the time needed to bring the system up to pressure was so short after sitting for a while. I took her for a drive and was very pleased with the result. I’m able to get into all gears reliably and the F1 system primes very quickly when I first get in for the day. As of right now, all leaks and shifting issues have been resolved. If anyone needs one of these kits, I can put one together fairly easily. PM me if you’re interested.