Running rough/misfiring?

[Wesley]

Hi all,
My bike has been running fine since I replaced the timing pick-up although, after my journey to visit mum in hospital, I found a fork seal had gone when I next saw my bike in daylight...Ohh the joys of buying a bike that was kept off the road. Anyway's I popped out to see a friend today only a short journey (about 20 miles). Bike started ok this morning and was running well around town whilst I did my chores, paid a few bills, bought fork seals/fork oil etc (another job for another day). Rode over to my friends and gave her a blast down the highway 75/80mph slowed to go through his village, the oil light came on for a couple of seconds and the bike was running rough. Sounded like she was misfiring or only running on 3 cylinders. Brought her home and anything less than about 20mph and she starts running rough again. Have stripped the side scoops off the fairing and checked all my connectors/wiring and all looks fine except for a small black box on the left side just above the scoop i took out. This box has a white connector with 8 wires running into it. all the terminals were green and when i popped the lid off the box to look inside it was full of water. It contains a small circuit board a few diodes and a relay. I put it back on and the bike wouldnt turn over unless i wiggled the wires 

Q1. What exactly is this box so i can get a replacement?
Q2. I know it caused my starting issue but can it also cause the poor running/misfire? if not...
Q3. Any ideas where to look to cure the running problem?

Thing's I've also checked.... Fuel, Carb gaskets (air/inlet manifold rubbers) no fuel leakage on carbs either, Spark plug boots (new plugs only done 300miles). I know I've only done a few basic checks but as usual I dont have access to tools/garage until sunday (brothers day off).

[movenon]

Welcome ! What year is your bike ? I am sure it will be easy to sort out. This is a stupid question with out knowing what year you have but is your fuel tank full ? If you have an "electronic reserve" (89 and newer ?) when the fuel gets low it will simulate running out of fuel (missing, cutting out etc.). If it's a first generation FJ the fuel cap "flapper" valve could be causing a vacuum in your fuel tank starving your fuel. That's easy to trouble shoot, crack open your fuel cap and see if it go's away (taking proper precautions not to spill out fuel while testing) Someone else will have to talk about the oil light and the box you are referring to. Perhaps a new box will solve all your problems. That's a start anyhow. Stand by on the forum, there are members on here that have an infinite more amount of experience than me. 

[Wesley]

  Oop's how could I be so stupid.... It's a 1990 3CV 
Fuel level checked(was low but refueled before my return journey), Fuel pump checked (making all the right noises and no leaks), Filler cap/Breather checked all appear to be ok.

[movenon]

Good, hopefully it is just that box that is causing your problem. It is a holiday (Thanksgiving) over here so it will be slow on the forum but someone will show up as the day progresses. I tend to forget about moisture problems that you have over there. . High and dry here.

[racerman_27410]

IIRC flipping the reserve switch to on should bypass that box. (to verify the problem)


KOokaloo!

[radiotek]

I'm curious why moving the wires on the 'box' fixes the start? can you take a photo of it?

[Wesley]

I'm curious why moving the wires on the 'box' fixes the start? can you take a photo of it?

Unfortunately not as i haven't got a camera, However I visited a breakers/repairers to get some help earlier they told me it was combined flasher/fuel pump relay. Charged me £20 for another and i now have indicators (hadn't noticed they weren't working  )

Also they looked at my misfire issue and said it could be a bad earth or the coils breaking down gotta get some tools and delve a little deeper as she's currently running pretty damn awful below 3000 rpm although the issue seems to vanish after 3000 rpm. He did put a tester on the plug leads and confirmed I'm losing spark, Just hope it isn't the replacement pick-up going pop. ~More bad news~ I have a 100mile journey to do tomorrow and I have no choice but to take the FJ even whilst she's running as crap as she is.. i do hope i don't hurt her anymore than she already is 

[racerman_27410]

if she clears out above 3 grand then you just need to do a thorough carb cleaning... sounds like some gunk in the pilot jets to me as well as maybe some plugged holes in the emulsion tubes..


KOokaloo!

[radiotek]

None of that water get in the tank did it?