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Posted

I'm afraid I'm usually asking for advise and not giving it. But here goes another...

I have a really bad (barely rideable) misfire on my V11. Started the other evening just after filling up with Shell V power.

Symptoms are very bad mis (cutting in/out) on neutral throttle position/small throttle openings, and BIG bangs / backfires on closed throttle. But it runs great on a wide open throttle.

So far I have

Changed the fuel.

Changed the plugs.

Checked the phase sensor (it's 720 Ohms)

Checked the Air & Oil temp sensors (Both 3 kilo Ohm)

Replaced all relays for the old ones which were OK

I've cleaned all the electrical connectors under the tank while I was there too.

Checked the side stand and clutch cut-out switches.

 

Then I checked the TPS. And it WAS 350mV at full closed. So I adjusted as per instructions and it's now 150mV at closed and 4.8V at wide open throttle. And still the misfire gets worse.

 

The bike's un-rideable, and now the fault occurrs from cold and the bike just kangaroos and jumps around like mad at anything less than a full open throttle. At full open it feels good, till you close and the back-fires start.

 

Ideas welcomed...

 

Thanks

 

Rob

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Posted

 

The bike's un-rideable, and now the fault occurrs from cold and the bike just kangaroos and jumps around like mad at anything less than a full open throttle. At full open it feels good, till you close and the back-fires start.

 

Ideas welcomed...

 

Thanks

 

Rob

Sorry to hear it, sounds like my bike was a week or two back

I was having battery problems, battery would drop to 10V, tacho would cut out. I think the voltage dropped so low the injectors would fail to open occasionaly

or

If you have a Power Commander try removing it, that gives a different set of injector drivers. (mine cuts out on one cylinder at times)

or

Try my intermittent fault detector to see if you are loosing power at some critical point, this will drop out if you loose power e.g. to the ECU for even a split second. Just use a spare relay. Connect it on to a point you suspect, next time it misses if the relay is still energised you can rule out that point and move to another.

Hope this helps

Roy

Troubleshooting Tips.pdf

Posted

Check your intake rubbers between the throttle body and cylinder for tears and make sure the throttle bodies are fully seated and the clamps are snug.

 

If the bike was running fine before that fillup I think your resetting of the TPS by 200mV may have done more harm than good and your running lean. In my experience getting the TPS reading at idle to about 525mV is much more important than getting the 150mV reading with everything disconnected. If you check or reset the TPS again slowly turn the throttle and check to see that the voltage increases smoothly with no dead spots.

 

That's all I got right now :huh2:

Posted

 

Ideas welcomed...

 

Thanks

 

Rob

On further thought.

If you suspect it's electrical get a small lamp and thread it through the hole in your brake lever. One wire goes to ground and the other to one of the points I indicate, just jamb it in the socket along with the relay or wrap around the pin.

As you are riding this allows you to monitor the voltage at the test point, if the bike starts playing up and the light's flickering it tells you there's a problem before that point, if it's not flickering you can cross that off your list and try a different point.

I like to use an LED for this because they are much more visual than an incandescent or a multimeter for that matter. I carry one on the bike as a simple troubleshooting tool.

If you don't have a 12V LED just make one using any LED and a 1K resistor.

Have you ruled out loose connection in the relay bases?

Good Luck

 

Roy

Missing.jpg

Posted

On further thought.

If you suspect it's electrical get a small lamp and thread it through the hole in your brake lever. One wire goes to ground and the other to one of the points I indicate, just jamb it in the socket along with the relay or wrap around the pin.

As you are riding this allows you to monitor the voltage at the test point, if the bike starts playing up and the light's flickering it tells you there's a problem before that point, if it's not flickering you can cross that off your list and try a different point.

I like to use an LED for this because they are much more visual than an incandescent or a multimeter for that matter. I carry one on the bike as a simple troubleshooting tool.

If you don't have a 12V LED just make one using any LED and a 1K resistor.

Have you ruled out loose connection in the relay bases?

Good Luck

 

Roy

 

air leak? ignition switch?

 

Roy, thanks for the trouble link..

Posted

Thanks for replies

This morning I went round checking earths.

Disconnected and by-passed the PCIII

Re-shimmed the phase sensor a smidgin closer

It sounds different, but the problem's still getting worse.

Still no FI warning lights either

 

I think I'm going to need to try Roys method some time soon.

 

Rob

Posted

Well many thanks to all...

I don't quite know why, but after following the TPS setting instructions http://www.v11lemans.com/forums/index.php?showtopic=12204

to the letter (and I mean +/- nothing) it's now running 95% fixed.

I don't know why this fault would develop within 50 miles of riding though, maybe I did pick up some bad fuel and then proceeded to upset all my settings before the bad fuel was through the system?

Anyway as I say. 95% fix

Residual problems are...

Revs don't die as quickly as I'd like (slower than before)

Still missing/coughing/fluffy between 2500 & 3300. I know this is a dodgy area with V11s anyway, but it's a lot worse than previous?

I'll recheck and rebalance tomorrow to try and iron out fully, but can anyone tell me whether I need to alter the TPS settings if I have a PCIII and K&N fitted (as I do)

Thanks to all (esp dlaing)

Ta

Rob

Posted
Revs don't die as quickly as I'd like (slower than before)

This is your second sign of air leak in intake rubbers. Check clamps and look for cracks (some surface cracks are normal, as long as they don't go through).

Posted

This is your second sign of air leak in intake rubbers. Check clamps and look for cracks (some surface cracks are normal, as long as they don't go through).

Popping & banging on the over-run has pretty much stopped though. And I did spray them up with WD and nothing.

They look in good order, and the clips were tight.

I can't discount them, but I think it unlikely. If the problem re-emerges, I'll def be looking very closely at them.

Cheers

Rob

Posted

Popping & banging on the over-run has pretty much stopped though. And I did spray them up with WD and nothing.

They look in good order, and the clips were tight.

I can't discount them, but I think it unlikely. If the problem re-emerges, I'll def be looking very closely at them.

Cheers

Rob

 

Mine tends to backfire when hot as wel. I now have the TPS set at 175 mV at fully closed and 550 mV at idle, combined with 1/4th turn loose for the air bypass screw instead of 1/2. It makes the mixture sligtly richer and delays the ignition at 2000-3000 rpm and almost closed trotle.

Runs fine that way.

Posted

Hi

Got it running pretty good Saturday. Then today I took the rubbers off the TBs and checked them out (fine) then altered the TPS to 170mV Closed and 550mV Idle and it's awful. Backfiring plenty again on part throttle openings. I went out earlier and it blew the RH TB off twice before I could get home.

 

Just going to try taking the PCIII off and give it another run.

 

Rob

Posted

Still ran rough as hell with the PC disconnected, still kangarooing/missing/banging etc. So re-connected the PC and dialled 150mV on the TPS fully closed, which seemed pretty good last time. This time awful again - barely diferent. Took it out for 3-miles and it blew the RH TB off twice.

I'm thinking that although the TPS appears OK on my digital meter, maybe there's some spikes that aren't registering?

Otherwise I'd appreciate any other ideas.

Thanks

Rob

Posted

One way to check the TPS is to disconnect it and check the resistance across the contacts. As the throttle as opened very gradually, there should be no "jumps" in the progression of resistance. When my TPS played up, I could not find it checking the change in mV, but the resistance reading showed the "jump" very distinctly.

 

That said, you may not have a TPS issue at all. intermittent spikes in the charging circuit will also do this. Check the charging voltage while opening and closing the throttle while running. Again, there should be no "jumps" or interruptions. Unfortunately, this is not a very sensitive test. Perform the "wiggle test" while observing the charging voltage "wiggle" the yellow alternator wird and the harness to the regulator.

 

Look at your 30 amp charging fuse for melting or burnt contacts. Also, inspect the yellow wires under the alternator cover where they are (or should be) soldered to the stator.

 

You mentioned your "FI warning light." What's the status on that?

Posted

One way to check the TPS is to disconnect it and check the resistance across the contacts. As the throttle as opened very gradually, there should be no "jumps" in the progression of resistance. When my TPS played up, I could not find it checking the change in mV, but the resistance reading showed the "jump" very distinctly.

 

That said, you may not have a TPS issue at all. intermittent spikes in the charging circuit will also do this. Check the charging voltage while opening and closing the throttle while running. Again, there should be no "jumps" or interruptions. Unfortunately, this is not a very sensitive test. Perform the "wiggle test" while observing the charging voltage "wiggle" the yellow alternator wird and the harness to the regulator.

 

Look at your 30 amp charging fuse for melting or burnt contacts. Also, inspect the yellow wires under the alternator cover where they are (or should be) soldered to the stator.

 

You mentioned your "FI warning light." What's the status on that?

 

Thanks

Charging seems steady state. 14.2/14.3 at 2-3000 rpm

No differences wiggling wires

No marking on the 30A fuse

However, re the TPS, between the outside pins the resistance is linear, but between the centre and the bottom pin the resistance drops, then picks up again, then continues to drop. Could this be thee culprip?

I'd have to be unlucky. A previous owner had a bill for £505 GBP for diagnosis and replacement of the TPS.

 

There is no fi warning light coming on, but then perhaps there is no fi warning light. The mechanic at the local dealer said there was a light, I assumed it's be the low fuel light doubling as a fi warning, but now I'm thinking there isn't one. There's no mention in the handbook.

 

Thoughts appreciated

Thanks

Rob

Posted
However, re the TPS, between the outside pins the resistance is linear, but between the centre and the bottom pin the resistance drops, then picks up again, then continues to drop. Could this be thee culprip?

I'd have to be unlucky. A previous owner had a bill for £505 GBP for diagnosis and replacement of the TPS.

That does not sound right. Maybe this is it, though I've never heard of anyone having to replace it twice.

 

Otherwise you could try wiggling the cable to the timing sensor too. Some have had problems with it, despite reading good when measuring for resistance. Most problems seem to be with the V10 though, as the cable is forced into a 90 degree bend on that engine (if memory serves me, anyway, something like that).

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