Ok so I have an 02 F4i and lately I can't even ride it because its surging so bad through the whole power band, doesnt matter what gear or RPM im in. This problem has been going on for the last month and I can't figure it out and its driving me insane!! I changed the plugs, even had it put on the dyno and the tune looks fine everything is how it should be. Someone mentioned to me to change the cam chain tensioner but they said it sounded more like a rattle and I dont think thats the problem im having. Feels like a wiring issue or fuel problem but my injectors were also fine. Im seriously out of ideas so I thought I'd ask you guys. Thanks for any help in advance!

Mike

 

Had the EXACT same problem. Replace your Fuel Pressure Regulator. Its located on your fuel rail underneath your gast tank. I replaced mine and now it runs perfect. I'll put money on it that it fixes it. $60, 20 min easy labor, and some spilt gas and your done.

 

+1
Sounds like the problem. Be ready to plug the line that goes into the regulator, it will drain until the tank is empty if you don't.

 

A golf tee works amazing for that.

 

Thanks alot guys I appretiate it, Ill buy a FPR and give that a try hopefully it works!