Alright I'll try to make this short.

I bought an 02 f4i from my friend. He bought it new and after a few years started having trouble with it cranking all of the sudden. It will start eventually or you can push it off. If you keep it running till it gets warmed up it rund pretty good but has a little hesitation on the low end.

he took it to the dealer and they gave him a bunch of different storries: MAP sensor, IAT ECT..... Then they said that it needed some sensor inside the throttle body that couldn't be removed and that he would have to replace the throttle body..

I bought it and found a full set of throttle boddies on ebay with the airbox, boots, inj, MAP, IAT Fuel rail intact. I swapped the whole set up, and it still does the same damn thing.

It reads a trouble code for the MAP but the sensor checked out fine.

I did clear the trouble codes after the swap and it came back

Could it be the ECU??

Any help or suggestions on something i didn't check / swap would be great!!

 

Still no luck, It keeps fouling plugs[:@] Those dam things are 70 bucks.

I reset the ECU afer I got it warm and running and rode for an hour. The Map sensor FI light never flashed but it still has trouble in the low end and now i've fouled another set of plugs trying to crank it.

It only seems to through a light while i'm tryin to crank it and i have the throttle gapped. makes me think maybe not FI related.

Could it be the Coil packs or whatever they're called?

 

I've had this trouble with other bikes, but they were carbureted, so this may not help. This was, for me, usually caused by a rich condition. But rich usually means it has a lot less trouble starting. What do your plugs look like? Covered in carbon means rich. I forget what means lean, i think they'll be really burnt up.

If you have any more details, that might help.

By the way, plugs are a bitch to change on my F4i, do you have a good way of doing it? Or do you do like me and suffer and beat the hell out of your hands and fingers for about fortyfive minutes?

 

how do u reset the ecu

 

Holy thread resurrection Batman. Lol. This thread was from 6 years ago. Bravo on using the search button though

 

+1

 

you dont exactly reset the ecu itself, you just reset the MIL(FI) code memory. this erases all the codes currently stored in the ECU. to do this have the ign switch OFF, then jump the service connector(connector w/ only a female end off the ecu, i believe its orange). then turn the ign switch on. while the MIL light is on, remove the jumper wire and then reinsert it into the service connector again. the MIL will start blinking if done correctly.

after this if the bike throws a code you know for sure that it is currently a problem, and not an old code. but IIRC it only shows new codes anyway when you put the sidestand down.

is OP still on the site? curious as to why it would foul plugs from a map sensor error. i would think the preset value would be good enough for the mixture. since the map sensor doubles as the baro the map code is pretty common on f4is, but usually isnt an issue. i chased the same problem down for months..

 

He was around this past September. Might be able to reach him via pm.

 

i resent ly bouth an f4i and the fi ligth **** on wile riding dont knw y but it stais on till i turn off the bike ..i also smell gas is this normal

 

My bike was hesitating and running rich, fouling plugs etc... Alot of times this is due to a bad fuel pressure regulator providing too much fuel. It is not too hard to swap out and like 50-60 bucks new. I would search some of the FPR posts and cross reference with your symptoms. Hope you figure it out!