Fuel Pump, Regulator, or just loose wires? fe390

So i bought my first enduro bike around 2 months ago an fe390 however i have been plagued with injection problems for around 15 of the past 20 hours that I have owned the bike and ive been slowly working out the issues.

The injector has been replaced as a precaution(and to give me a spare) and ive protected it with a golan super mini. I have also bought a fuel pump and regulator kit which is not yet fitted, but it includes all the in tank filters for when i do soon.

Like many on here I have been plagued with a bike that only cuts out when hot and riding in slower places and the problem is slowly getting worse, usually picking the bike off its back wheel and dropping it around 4 or inches is enough to make it restart.

SO yesterday after the injector and filter were installed i set off on a trail and surprisingly the bike ran very well for most of the session (although 100% power still not there and road top speed lowered i said ill replace the fuel pump next).

When leaving the trail the bike began to backfire and just before i got back to roads it started to cut out on me.

something strange that i noticed during this time and the last breakdown is that sitting on a certain part of the seat seemed to cause the fuel pump to turn off. driving a few miles standing on the pegs and i could sit down again until i got into another slow section and the exact same problem begins again, I even got off on the side of the road and disconnected the fuel regulator plug and made sure all the fuses were properly seated but that made no difference. the connections to the battery all seem good and secure also.

Today the bike was suffering the exact same issue FROM COLD so i said i need to investigate further before i go installing the full fuel pump and regulator kit.

I noticed that when i take the seat off, and press down on the top of the fuel tank (where the regulator is) that this actually causes the bike to cut out, it also stops the fuel pump running if i hold my hand down ontop of this part of the tank and i turn over the engine to prime it.
but the problem isnt always there as after doing it a few times i left the bike for a few hours and the problem seemed to have gone away.

there is an FI code flashing but i havent done the pin 5 and 6 bridge to see it properly.

before i go replacing anymore parts (although im gonna do the whole fuel system at this rate anyways) just wondering has anybody else ran into similar issues surrounding their fuel regulator and how they solved it?

Thanks

have also just noticed that it seems my seat has not been fitting on properly for a while, and is kinda difficult to get properly installed onto the bike with both lower lugs catching securely, there is also evidence the center support rib of the seat (just to the left of the husaberg logo and part number) having rubbed on the regulator unit, so obviously this has been putting pressure on the fpr housing unit.

thank you guys for the replies, since the tank has to come out any way I will inspect both of these places however that loose earth on the fuel pump thread sounds mighty similar to my symptoms, specially when i press down on that specific part of the fuel tank where the wiring joins to the plug beside the fuel regulator.

Will report back when i find out more, if its not that part of the loom i might even try to re route is as preventative maintenance, with the exception of my fuel problems this bike has otherwise been amazing so im keen to get it back to its former self.

thanks.

just to update on this i started the bike again last night and the problem has dissappeared once more, so i took it for a couple of miles today and it did not stop on me, I practically performed cpr on the tank making it flex in the same part that was stopping the engine yesterday and it just kept going.


had a bit of time tonight and i was still curious so i took the tank off thinking i would replace the regulator, but the one that I was supplied will not fit so i need to get a replacement, not a huge deal it is an easily accessible part.

I did not notice anything strange looking in the regulator so just put it back, however the wires which connect to the fuel pump plug looked slightly melted(this is also the area of the tank i put pressure on). not sure if they are supposed to be this way or there has been some undue heat on this particular connector. have included a pic so maybe you guys can tell me if its supposed to look this way it could be a melt or it come be some weird factory type seal i dunno about.



have also noticed that on the pics of this part on ktms that wire has a big insulating plug over it instead of 2 spade conectors like this, is this pump wiring original for husaberg?

put everything back together and when i went to start it i pressed the starter button slightly a few times to prime it, well by god, throttle response seems like it may be returned to normal feeling, engine idle sounds a lot stronger and there is less of a noise in the clutch area, ran the bike like this for around 10 minutes and all seemed good so i shut it off for the night and will do a little test run tomorrow.

Is it nessesary to spin the fuel pump like this when you have had the system apart in order to prime things as its not something i had done every time i had taken the fuel system apart before, and the 2 occasions where I did it tonight both seemed to help clear up the issue (although tomorrow on the road will only tell for sure)

Thanks for the help as always

Apologies for the triple post, however i just wanted to update again with my latest progress on the matter as i feel I am very close to pinpointing this issue now.

After reassembly last night, and with everything running nicely and strongly i decided to go for a little drive this morning, only running errands around the locality nothing to serious.

once things had warmed up I could feel a big difference in how the bike was running, full throttle has once again become a no go in the lower gears as the front wheel tries to pop up as it was before.

so i headed out a quiet main road and got up to 6th gear speed, then dropped down to 40mph, when i bought the bike first it would handle this condition no problem and pull back to 60 without effort, however when the fuel system is acting up the engine would complain and labour as i would try to do this. today this was not a problem it was happily chugging away at 40mph without much of a complaint.


so im becoming more confident now the problem is/was in the fuel regulator, im wondering is/was it dirty and have i disturbed that dirt in my reseating of the FPR? very strange indeed, how exactly does the FPR operate on these bikes?

thanks again.