So last year I got my first road bike, prior to that was motocross. It was a 1989 Katana 600 and it barely ran. I tweaked the carburetors forever but I never got it running quite right. So, I saved some money and recently I bought a 2001 F4i.

Now, when I bought it, it ran a little weird. When I would turn it on, it would idle around 600rpm for about 5 seconds then the FI light would come on and the RPMs would go up to 2000. While riding the bike it would run perfectly (omg so smooth vs carbs). Anyway, I pulled the code and it blinks twice which tells me MAP sensor. So I wanted to get to work fixing it and in the process I ****ed two things up.

1) Midway through my quest (I had the gas tank off) a security guard told me I couldn't work on a bike where I was...so I had to put everything back together and move to a different spot. After putting it together I tried starting it and it started fine, but it was like the throttle was at WOT. The bike just revs up to the rev limiter and I have to cut it off.

2) When I was working on it in the new spot, I put the fuel tank down and pinched the fuel pump's wiring harness which fried the green wire (ground) on the harness on the fuel pump side. I have since fixed this by soldering a new wire from the fuel pump's body to the harness.

However, the WOT throttle and the MAP sensor issues remain. While rummaging around under the tank yesterday I found a vacuum line going from the middle of the throttle bodies (a large splitter) over to the left side and not plugged into anything. Looking at the service manual it looks like this should be plugged into the MAP sensor...so I think I've solved that problem...but what about the WOT? What could be the cause? When I turn the throttle it has resistance and it feels like the throttle bodies' butterfly valves are closing (i hear a click) but the bike just wants to rev rev rev. Could this be the TPS?

Anyway, I'm going down now to pull the fuel tank off again and check out the TPS. If there's some sort of reset procedure that's required to reset the TPS or the ECU please let me know. I never disconnected the throttle cable nor do I recall disconnecting anything other than one fuel line.

Thanks everyone, I was so happy to get this bike and I ****ing love the thing...and now I'm devastated that the first thing I do is f*ck it up. I'll be posting an intro and more info about the bike momentarily (the broken thing is on top of my mind right now).

Regards,
-Duo

 

well you're not gonna like hearing this BUT first thing you need to do is lift the tank back up and inspect all those wires well. i would hate to hear that its a grounded out wire causing your prob and tommorow it runs fine but grounds back out while you're riding! then i would diagnose the tps. if you dont have a manual already you can DL it here http://www.carlsalter.com/motorcycle-manuals.asp and then use the specs to check it. as for your orig prob....mine did the same thing to the T because that vaccume line had a cut in it. and if you want (wont hurt) you can try resetting the ecm by disconnecting the batt for 10 min before all this diagnosing. but even if that works(good luck) i'de still inspect that wiring under the tank.

 

I would check all throttle cables and vacuume lines for a snag or something. Sounds like you throttle valves (butterflies) are stuck open or not fully closing.

Just pop off the airbox and check while you turn the throttle (bike off)
This is my first thought after hearing that the thing is redlining after you start it up.

 

Problem Solved. Very idiotic and can't believe I didn't catch it yesterday.

So, problem number 1, the wide open throttle. My entire throttle body rail wasn't on the intake ports. like literally way disconnected...I looked at the screws and they weren't tightened at ALL. So I took off the airbox and put the things back on there and tightened to screws all the way down.

Problem number 2, my FI light and high idle. The vacuum line that's supposed to go to the MAP sensor was disconnected. Wow that whole error code thing really is awesome. I'm impressed by how smart the ECUs of today are. It blinked error code 2 -- bad map sensor or vacuum line to map sensor disconnected.

My f4i is now running very well...aside from a small rattle in the front fairings around 4-6k rpm...but that's just probably something not screwed down.

Thanks all!

-Duo Maxwell

 

Does this sound like a buzz?? My bike developed a buzz right at 6k RPM's that sounds like it is coming from my gauge cluster. But since its never really caused a problem I just leave it alone.

If you figure that one out let me know so I can try and if mine is the same thing or not.

And good job on getting her running again. I think besides riding my bike the second funnest thing to do is tinker with her to get her running better!!

 

for the buzz check your windscreen. just reach out and press on it when you hear the noise. ive found a few making that vibrating noise there.

 

If the buzz is coming from the right side i would guess it is your cct (cam chain tensioner) that needs to be replaced. Mine buzzes but I have more important things to worry about 1st...shouldn't hurt anythiing if ya dont replace it for awhile