The 01 F4i issue that no one can figure out. Not even Honda of Tupelo! Hummm
 

Ok, I still have the problem! It has to get fixed because I need the bike for mmi in january!!!! The bike stayed at honda for a month, they fixed nothing, rode it twice, and charged me 40 bucks. A guy that grad from mmi took a look at it. Checked the injectors and fuel pump. Both were great, I still think it may be the fuel pump, it could just have low psi when the bike decides to act up.

Ok another run down on whats up. The bike seems to feel like someone tugs on the bike ever so slightly a few times before it does the quick pause and then right back to smooth running. But if you pull in the clutch it dies. If you try to restart it now the bike will not start unless you hold the throttle half open or let the bike set in the off position for a few mins.

How the bike acted previously... First time it acted up, Bike did the pause a few times, pulled in the clutch and it had a low idle. Cycled the ignition and it ran great again. Then it slowly got worse to where it would die after I pulled in the clutch. Seemed like it done it when I'd hit a bump in the road, so I checked all connectors and di-electric greased them, no luck! So I figured the bumps may cause me to let off the throttle a little which activated the issue.

Things ive checked... all the connectors, and they are fine. Replaced the fpr, ran great for a month, then this issue started. Plugs and oil were changed with the fpr. Done the tip sensor mod, had the problem before this mod. Did the cct mod, which doesnt matter in this case. Everything else is stock, with 7500 miles on the bike. Im running fairing less, with a stunt headlight, and no ram air tubes. This was all done a month before this problem.

This is a ghost issue because on a random day i can ride and it will not do anything it shouldnt. Then get up for work the next morning and go 100 feet from the house and it does this in between shifts. Seems like the issue is more likely to happen if you leave on a cold motor. When I do leave on a cold motor I short shift to be easy on the motor until it gets the temp up a little.

Things I think it can be.... A sensor, ecu, or the fuel pump. If anyone can figure this out it'd be great because im about to just start changing **** out till I get it. Might have everything new by the end of this but I'll be damned if something gets the best of me!

I have to have this bike for trans. at mmi, this is a go or stay home issue for me. So please everyone study this and please give a educated guess, And not the "did you check the battery connection" and "it could have water in the gas" replys..... Im way ahead of the simple stuff, promise.

It may be the fuel pump like your thinking. If the fuel pump randomly cavitates, it can loose pressure and kill the engine. Even a slight drop in pressure can kill the engine as the injectors require quite a bit of pressure to operate. However, I really don't know why pulling in the clutch would have anything to do with it. if the bike is starving for fuel because of the fuel pump, the bike would die regardless if the clutch was pulled in or not.

I wouldn't rule out the FPR again. Even though its been replaced only a month ago, it very well could be bad again. I would at least inspect it to make sure its not failing again. It sure sounds like the FPR is acting up again.

Do you have any other electrical things hooked up? I know you don't have the fairings, so I would assume you have some sort of street fighter set up.. So is it possible you have wires being powered from insufficient sources? What Im getting at is, if you have high demand power requirements, and are using a source that is not rated for it, its possible the wires could have been damaged internally. They may work for awhile, such as the month you mentioned, but after a period of time, the wires may not be able to withstand the high demand.

Have you inspected the throttle position sensor?

There should also be an air temp sensor that could cause some issues. I don't know that it would kill the engine, but could certainly cause irratic idle and surging.

I know, probably not much help, but unfortunately, these types of gremlins usually are only found by replace and pray.

Your helping just fine, intelligant answers is what im looking for.

I wanna add one thing it did one day to maybe give another helpful hint before I make a reply to your statment. One day I was riding to get the bike to act up and maybe help me figure out something. I was setting at a stop sign idling talking to a friend. The bike went from running smooth to a low idle. I reved it a few times, not hard revs either and the bike smoothed back out and returned to correct idle rpm. Maybe that will help also.

Ok, Im with you on everything you posted, I agree with most. The only thing I dont agree with is the fpr. I was thinking like you until I was taking a shower a minute ago thinking about what we thought. But I think now, If the fpr was going bad again it would be a more common problem, like everytime I ride it. Reason being is because the fpr has a simple task, and does the same thing everytime you ride the bike. Its to simple of a part and has to simple of a function not to mess up everytime. That being said, I may be wrong. How could I inspect it to see if anything is wrong, cause I can check it anyways.

Now the tp sensor, Ive thought about this one to but how could inspect it without riding around with a volt meter on it, hoping the bike acts up. That goes for the air temp sensor also...

The fuel pump, the guy from mmi checked the psi and said it was about 14 psi, I think. Some where around that anyways, but that was with the bike running properly. Said the fuel filter was good also. I still think it could be the fuel pump because when it does the pause, technical it is dying but it starts back from engine momentum. Liking pushing a car off from a dead battery. If I had to guess... But the day it did the low idle at the stop sign, it should of died. Unless it could have been the most minor change in fuel psi ever! My luck, I wouldnt doubt it...

As far as electrical **** goes. The only difference from stock is where I wired in the stunt headlight to the factory headlight connectors. High and low beam. And the tip sensor mod, which was done after the problem started.


:icon_no:

fuel filter maybe? the petcock in the correct position?

Im reading on the net and stock fuel psi is suppose to be 48-50 psi. How the hell would it run on around 14psi? He must of checked it wrong, may need to retake mmi classes!

I've learned from my classes that just because ppl pass n grad doesnt mean they know a dayum thing lol

That guy from mmi said fuel filter was good, but if he doesnt know the proper psi who the hell knows if its good! Ill get around to looking at it, may just change it for the hell of it. And what petcock? Only petcock I know of is on carb stuff. Where is it on fuel injection?

agreed:)

Playfulgod, if you can discribe where it is and what it should look like, I can find it and check it out.

Edit*...

I know what it is, just forgot it was called that lol. Ill go check.

umm the F4i may not have a petcock anymore, the F4 does, its just set to use the res+ all the time.

Yeah it doesnt have one. I didnt remember ever seeing one on a fuel injected bike.

I just talked to the guy that went to mmi. He said he knows he checked the fuel psi right. So could the bike even function properly like this, with ~14 psi? I wouldnt think so... Maybe his gauge is off.....

Correction. he said 38 psi. So would it even run as good as it does off 38?

Did he mention how he measured the pressue? If he measured after the fpr does its job, the the pressure will be less than 48-50 psi the pump is required to pump. the pump itself should put out the 48-50, but the injectors are probably only using the regulated 38 psi. So it depends on what he measured and where. He may be correct. If the injectors are requiring 48-50 psi, and your only seeing 38psi, either the pump or the fpr is failing.

As for if it would run or not on 38psi. Again, it all depends on the range the injectors are rated for. In all honesty, injectors don't kind of work. They either have enough pressure to open and spray the gas, or they don't. So if your pressure is dropping below what the injectors require to work, the bike would simply die, not just idle low, which makes me think tps or temp sensor.

On the throttle position sensor, you should be able to unplug it, measure the resistance at no throttle input, then again at full throttle to see where the resistance is. If its within range, its not the problem. Sorry, I don't know what the specs are. But an ohm meter is what you will need to use. If I had to guess, your current setting on the tps is on the edge of being within the idle range.

As for the temp sensor. I've never tested one, but I believe there is the same basic resistance check for it as well. There should be a range of resistance for it to fall in at certain temps.

Hopefully you know someone who get you the proper specs to test those items with.

On the petcock, I don't know about the F4i's, but my wifes fuel injected 636 had one. However, it wasnt the same as carbed bikes. It was actually under the tank, basically just an on/off switch for removing the tank. If your bike has one, make sure its open all the way.

You've probably already been there, but make sure your fuel line is routed correctly and not kinking at all.

Do you have air box mods beside the removal of the air tubes? And this is a long shot, but sometimes, the removal of the air tubes can create disturbances within the air box that normally wouldn't be there. The tubes can smooth out the air flow, when removed, the air just tumbles around in the box. I don't know that it would affect anything on that type of injection where the injector is bolted directly on the throttle body, but it does make a difference on certain models with the injectors set apart from the throttle bodies. Again, probably not the issue, but just something to consider.

How is your voltage? Do you have a good ground? Reason I ask is you say you rev it a few times and it goes back to normal, but if at idle it will start to fall. Voltage may be dropping low enough to cause the pump to loose pressure.
I myself would check grounds and then the voltage regulator. Just my .02

The low idle and then rev to correct only happened once. I seriously doubt thats the issue. And yeah all the grounds are good.

[quote=justasquid;954768]Did he mention how he measured the pressue? If he measured after the fpr does its job, the the pressure will be less than 48-50 psi the pump is required to pump. the pump itself should put out the 48-50, but the injectors are probably only using the regulated 38 psi. So it depends on what he measured and where. He may be correct. If the injectors are requiring 48-50 psi, and your only seeing 38psi, either the pump or the fpr is failing.

Idk where he checked it from but im gonna recheck it myself this week. If I wanted to check after the fpr, how would I go about this? Its on the fuel rail. What do I remove to check from the rail? Also I think I read they are 50psi injectors some where, but that doesnt mean they are suppose to run max psi..... im guessing.

As for if it would run or not on 38psi. Again, it all depends on the range the injectors are rated for. In all honesty, injectors don't kind of work. They either have enough pressure to open and spray the gas, or they don't. So if your pressure is dropping below what the injectors require to work, the bike would simply die, not just idle low, which makes me think tps or temp sensor.

I agree, where is the temp sensor to check it?

On the throttle position sensor, you should be able to unplug it, measure the resistance at no throttle input, then again at full throttle to see where the resistance is. If its within range, its not the problem. Sorry, I don't know what the specs are. But an ohm meter is what you will need to use. If I had to guess, your current setting on the tps is on the edge of being within the idle range.

Got a question, does the bike have to be running to check wot ohms? Do you know where I can find the correct specs?

As for the temp sensor. I've never tested one, but I believe there is the same basic resistance check for it as well. There should be a range of resistance for it to fall in at certain temps.

Hopefully you know someone who get you the proper specs to test those items with.

On the petcock, I don't know about the F4i's, but my wifes fuel injected 636 had one. However, it wasnt the same as carbed bikes. It was actually under the tank, basically just an on/off switch for removing the tank. If your bike has one, make sure its open all the way.

You've probably already been there, but make sure your fuel line is routed correctly and not kinking at all.

Yeah its correct.

Do you have air box mods beside the removal of the air tubes? And this is a long shot, but sometimes, the removal of the air tubes can create disturbances within the air box that normally wouldn't be there. The tubes can smooth out the air flow, when removed, the air just tumbles around in the box. I don't know that it would affect anything on that type of injection where the injector is bolted directly on the throttle body, but it does make a difference on certain models with the injectors set apart from the throttle bodies. Again, probably not the issue, but just something to consider.

No, but people stunt most bikes without air tubes, even on f4i. A friend of mine rode a season without them on his f4i and all was great.




If anyone can find me the correct specs on fuel psi after fpr, correct ohms of the tps sensor and the temp sensor, it'd would be awesome! And I would deeply appreciate it.

Oh well, I tried. Good luck and keep us posted with more symptoms. Where are you located? If in SoCal you can stop by our shop and we can get a better idea of what is going on.

Im in Mississippi. Idk what im gonna do about this.... No one is willing to figure out this problem and I dont have the tools at home to check anything electrical.

If you have a pdf reader, you can go here and download the service manual which will have all of the specs you will need.

http://downloads.hondatech.info/Moto...e%20Manual.pdf

You can then save a copy to your computer. It does take quite a long time for it to load, at least it does for my computer, around 3 minutes, where all there is a white screen, but it does load. If it doesn't load for you, I downloaded it just to have it and can email it to you if it doesnt open for you.

regarding your tools, multi-meters have become extremely inexpensive. You can pick up a decent digital multi-meter for less than 30 bucks. Try your local autoparts store or even places like walmart have ones accurate enough to diagnosis most electrical problems.

Lol I downloaded the service manual a few hours ago, but thanks anyways!

Ok here is some new hints. I put the gauge cluster back on. When the loss of throttle, or hp happens, the FI light comes on solid for about 2 to 3 seconds and then goes back off. After it goes off the bike returns to normal. If you pull in the clutch while the FI light is on the bike dies. To restart bike you have to turn the throttle a 1/4 to 1/2 throttle, After the bike restarts it idles low, kinda like it trys to catch up until it returns to normal idle. The bike also feels like your braking very very softly at steady speed and going down hill when steady on the throttle or maybe letting out just a little to keep the bike at a constant speed, this is a off and on thing. But no FI light. When the FI came on I hit a bump in the road or hill a bump going down hill. But this does not happen on every bump, usely the bigger ones where the rear tire might slightly leave the ground. I think its confusing something..... I guess. I checked all connections again and started the bike and wiggled all the wires, trying to trip it up...... no luck there. In WOT the bike still preforms how it should.


I checked the ecu because the service manual said to if the bikes FI light blinks 33 times. Being on constant between 2 to 3 seconds equaling 10 blinks a second x 1.3= around 33. The ecu checked out.

Other sensors around this time frame was a 02 sensor and 02 sensor heater. Those are probably not the issue.

Read up on the tp sensor. Said to check the connection if the FI light didnt come on when the ignition is turned on. And it was good.

What do you guys think I need to attack first?

Any one wanna send me a bunch of f4i electrical stuff and ill buy whatever I need to fix it when I figure it out? haha

ive had similar problems in my car when I wasnt running a front o2 sensor and needed a new map sensor. Have you changed or looked at these?

damn dude... i was all pumped to get a fi bike kus my carbs gave me mad trouble earlier this summer but now after reading this it sounds like its ever harder to find the problem when something goes wrong and some seafoam wont do the trick