I believe the fuel pressure regulator needs to be replaced on my 2003 F4i. I read somewhere that in order to test this, I would need to remove the vacuum hose from the FPR and turn the bike on, then if gas comes out of the FPR then it's going bad or already gone bad. Can anyone confirm this for me?

Right now my bike is very sputtery and seems to want to die after 5-10 mins of riding. It gets progressively worse until it shuts off and the throttle needs to be cranked for it to turn on again. The gas smells extremely rich and the exhaust is white. Are these all symptoms of a bad regulator?

I removed the vacuum hose and turned the bike on and some gas came out but it wasn't a lot. Like a small steady stream of borderline drops but not heaving spewing or anything. Is this the cause of my problems?

The bike also came with a hindle bolt on exhaust with no power commander. Do I NEED a power commander in order to make the bolt on work properly? I found a stock exhaust locally for 50 bucks I could pick up tomorrow. I'm a novice rider (just passed MFA 2 weeks ago and full road exam yesterday) and don't necessarily want to spend 300 on a power commander when my experience isn't high enough to warrant more power than the bike already provides.

Thanks guys

 

Definitely a bad FPR had the same issues

 

Thanks.. Ryan? lol

Does having a bolt on exhaust without a power commander also cause problems like this? I'll replace the FPR first and see how it runs before dropping 50 on a stock exhaust.

 

I also wanted to mention the bike has 3000 miles on it and has been sitting for 7-8 years without any proper care during this time.

 

Your FPR is bad. It went bad from sitting with gas in it. You may want to run some injector cleaner, like seafoam, through it to clean out the injectors and change the fuel filter. Old gas is nasty stuff!

Your bike is fuel injected. It will adjust the mixture as needed, even with a new can on there.

 

I ran some injector cleaner in there already but I didn't realize the FPR went bad from sitting with gas in it. This makes sense now that I think about it.

I'm going to order the part right now!

 

When you go to install it, don't forget to remove the shipping plug on the new part....

 

+1 to what demon said about the plug. I have had a handfull of bikes come into my shop because people dont take the plug out. They do it themselves and then come to me saying their bikes wont start. The very first question I always ask is if they did anything to it recently. That normally helps to narrow it down a bit if they have. Good luck and let us know if you need any help.

 

After pure white exhaust, sputtery throttle, random stalls, impossible starts, poor performance, TERRIBLE mpg, rich rich gas smell, extremely jumpy idle and large random changes in coolant temp, it was all finally fixed today by changing the FUEL PRESSURE REGULATOR!

That damn thing, jesus. That part literally controls the whole bike as far as I'm concerned. I'm relieved that solved the problem because we were running out of ideas with with things to change with a bike that had been sitting for 7 years.

It doesn't smell like an oil refinery anymore. I rode it somewhat hard for 30 mins to clean out some of the crud that had built up in the exhaust. My neighbor whom has been riding for 20+ years took it for a spin and was very impressed with the acceleration on the F4i.

Anyway, that seems to have done it! Very happy and glad I don't have to continue making checklists with more things to change.

Thanks for the help guys.

 

...And another satisfied customer rides off happy. Gotta love this forum!