98 VFR ....cutting out

Hey everyone...

after reading all the relevant posts and replies on the forum...well not really all but allot..hahaha. I just felt i needed a few theories and opinions on whats going on with my bike.

Its a 98 model, basically stock standard. It all began when during a commute to work the bike's FI light came on and shortly after the bike died. Before that it would cut out at around 5krpm. Now after having it in the mechanics...it was diagnosed with a faulty cam sensor....go figure. two weeks later i have it back and do the commute thing again. Going there was fine...coming back in the afternoon....peak hour...car accidents...temp 100 degrees...... No probs....near the end though at around or just over 5krpm....there was a slight loss of power..like the fuel cut out or something. Straight away i pulled to the left lane just in case the bike cut out like before. Nothing happened and made it home about 5km later.

Now it seems it might be an electrical problem but where to start? im pretty clueless when it comes to bikes....and electrical systems... Is my RR on the way out? The mech in the previous diagnostic...said he found the current was irregular but after replacing the cam sensor everything went back to normal.

I have no other means of transport so i will chance it again tomorrow for the ride to work. Let me know what you think guys cos right now im thinking......get another bike...

 

Wow, seems like the mech didn't follow up well enough. To check the r/r, get out your trusty digital voltmeter. Start the bike. If it's a cold start, let the engine warm up a bit where you do not have the choke on. Set the meter to 20 volts and place the test leads on the proper terminals (positive to + and megative to -). Now rev the engine to about 5000 rpm. The reading on the meter should increase from about 12.89 volts (this should be the reading before starting the bike (also make sure the battery is fully charged if the reading is lower than this)) to between 14.5 to 15 volts.

I should make a note (could be long winded) here as the following happened to me: On my bike the connector from the r/r to the stator (3 prong with 3 yellow wires) burned thru. I spliced it back together, chargins issue fixed. While in FL over X-mas, the connection burned again. I repaired it, but now, the charging system did the following: Idle - about 1500 rpm, charging at 13.5 volts, 1500 - about 3000 rpm: charging increases to 14.5v, 3K - 5K, charging drops back to 13.5v. I replaced the battery, the stator, and thr r/r (tho I have since put the old one back on it) with no change. Dealer said as long as it was charging at or above 13.5v it was good to go. I was not happy with that answer. Finally, I decided on a little trial and error of my own. I unplugged the r/r, got some 10 ga and 12 ga wire, red, black, and yellow. I made my own connections: black to ground, red to battery +, and 3 yello to the stator connector. In effect, I bypassed the wiring harness. With the battery at full charge, I started the bike with the following readings: Idle: 13.5v; 1K on 14.5v+. My conclusion: somewhere between the r/r and the stator connector in the wiring harness is a short or increased reseistance or something which cause the faulty charging condition. My charging system charges like it should now. Hope this helps.

 

Hey Vman, thanks for the reply.

Well it happened again today. At first i thought it was just a slip of the hand on the throttle that caused the sudden drop but sure enough the FI light came on. Pulled over at a petrol station and let it sit for a little bit....pumped the tires...talked shit with the security guard...etc etc. Turned the bike back on no FI light and so proceeded to chance it and try make it home....40 odd kms.

Now the funny thing....about 500 metres from home...it cut out completely. Turn off and on ...FI light is still on and bike wont start. Still have dash lights and headlights. Grrrrr. Wait a minute or so and try again...nothing..bike is dead. So i wait 2 minutes ..lol....FI light is still on but bike will kick over.....so basically i give it a bit of throttle and volia it fires up.....FI light still on but.... Turn bike off and on again.....FI light is now off but engine oil light is lit. Bike starts and engine oil light goes off. Make it home and here i am now.

Im not sure if i still have my multimetre or not but will try what you suggested vman before i take it back to the mech.

02 R1 is looking mighty tempting right now....HA

 

I'd start with cleaning the battery terminals, and firmly reconnecting.
I used fine emery paper to scratch em clean.
Could be just a loose lead.... hopefully

 

maybe try some FI cleaner in your next full tank of gas, just a suggestion and this may be wrong too, maybe someone can let us know

Ride on

 

Read all the posts in this forum with a similar thread title.
My 99 VFR had similar symptoms and I checked every sensor on the bike before I found the cause. The ECU was not secured properly in the back, a wire to it was inthe make/break mode and causing the bike to cut out.

 

Bad connections do have a way of mimicking other symptoms, don't they John. I agree with also checking the ground connections and such. Do you have a service manual? It can be a great help in a lot of cases. Your first description sounded like it couls be an r/r problem, but the second one souds more like something else. Something else I learned is teh the r/r can be hit and miss, meaning it works and then it doesn't, at least in my case. I'll do a write up in another thread on this point. Hope you get it figured out. I am thinking I need to go get an electrical degree. That should keep me in the professional student column. lol

 

Ok guys not much of an update but the bike is currently at the workshop..... cut out again 500 meters from it actually.

This time i just rolled to a stop and the bike just cut out...and FI light came on. Eventually i started it again by use of the throttle but could smell allot of fuel. Dont know what that means but cant be good as the bike was already warmed up and was not cold. Mech later told me when they checked it out it was showing a few fault codes. As to what the fault codes mean they were still waiting on honda for a reply.

Capt John, i did read in another thread about the ecu causing problems when it was not connected properly or the wires had come slightly off....if so then that would be a simple problem to fix.

Right now im of the mind to sell it once the problems are fixed.....i use the bike for going to work....some odd 190km return and i cant have it in the back of my mind that is it reliable enough or is something waiting else to come up.

 

same problemwith my 98 last summermy wiring harness on the left side right next to the battery was loose,solder it back and it should be good.it worked for mine.you should be able to twist it a little and make the fi light go on and off

 

Ok guys another update but no good news.

Mech said that the on board diagnostics were pointing to 3 sensors on the bike as being faulty....but when tested....were found to be fine. What makes it worse is that in riding the bike out and about everyday for the last couple of days, he was unable to get it to cut out like i did. Now he has cleared the fault table and said that my best bet is to make a precise note of what i was doing when it cut outs again, what the bike was doing etc etc and then they can begin to try and work out whats wrong. He made a suggestion that the cdi might be faulty itself and maybe what caused the cam sensor to short in the first place, but to test it would cost a couple of hundred dollars.

A few guys at work have said that i should just take it to a honda dealer and then with their computer equipment find out whats going on with the bike..is it that simple ? now coming from a car background.....all that the manufacturers diagnostics computers do is just read whats on the ecu when connected. Except maybe in greater detail.

Oh yeah, the mech also said that all connections were fine and no burnt wiring or loose connections.

What do you guys think?

 

Have the bike back... rode without a sweat. Had the head bearings replaced whilst it was in the shop and geeze it turns so quick now....have to get used to that. If i have time today i will go over the bike with the electro sport fault finding sheet and see if i can find whats wrong with it.....