Another rough runner

[El Thermidor]

Hey all, I'm having trouble with my 2001 1150GS (single spark), with 51000 miles on it. I've not been using it much recently (kids, too much of a hassle moving the car) but gave it a run out a couple of weeks ago and all was good. Went to take it for its MOT and it was suddenly running really rough: like a misfire, but both sides, not uneven. It won't rev, the occasional pop from the exhaust, and idles lower than normal, often to the point of stalling.

So far I have changed:

- Fuel (drained as far as I could using the fuel pump, at the injectors, then added 5l of the posh stuff)
- oil, filters
- spark plugs
- HT leads
- Coil
- Injectors

I've also checked the plugs are sparking and the injectors are squirting when cranking, and both seem to be good.

Does anyone have any bright ideas what it might be? I'd kinda ruled out the hall sensor, as everything I've read suggests a failure will stop the bike in its tracks, but am I mistaken? I have already changed enough, I didnt really want to spend another few hundred on the off-chance.

Thank you!

 

[oblertone]

By your right knee.

 

[El Thermidor]

Not that unfortunately. Had that before, so was literally the first thing I checked

 

[squibb34]

HES seems the most likely to me, given the circs?

 

[Riceburner]

Internal hoses in the tank? It they are just beginning to perish you still get "some" fuel flow, but not enough to run properly.

 

[El Thermidor]

I pulled the fuel hoses from the injectors and cycled the fuel pump to empty the tank because siphoning didn't seem to work, and the fuel flow was pretty good: I didn't measure it, but I'd guess 100ml or so per cycle. Certainly more than the injectors use.

Can the HES fail partially like that?

In other news, the screws for the plastic alternator belt cover are seized so I'm going to have to drill them out (and presumably helicoil the remnants). Hopefully the HES screws are in slightly better condition.

 

[Mad Hatter]

The throttle cables can also be unseated at the splitter box under the tank, the symptoms you describe do sound like this

 

[El Thermidor]

Well, it wasn't the hall sensor.

To be fair, at the age and mileage, the hall sensor was probably not far away from failing, and replacing it wasn't the horror story I'd feared.

Will check the Bowden-cable divider and take a look inside the tank for perished fuel lines, although the noises it's making would lean me more towards spark than fuel somehow. But with the plugs, leads, coil and HES already renewed, what else is there?

 

[DrFarkoff]

Well, it wasn't the hall sensor.

To be fair, at the age and mileage, the hall sensor was probably not far away from failing, and replacing it wasn't the horror story I'd feared.

Will check the Bowden-cable divider and take a look inside the tank for perished fuel lines, although the noises it's making would lean me more towards spark than fuel somehow. But with the plugs, leads, coil and HES already renewed, what else is there?

All to easy to dismiss the cable unseating from the inner end

Check that the throttle quadrants are stopping against their stop locations !

Explain as if attending the mechanic for the first time .............

What was the thing that you did immediately prior to the failure

Did you add fuel?
Did You have the tank lifted ? Charge battery? reconnect a wire?
Was it raining outside and you had it parked out there ?
Fuel "flow" may be more than needed "BUT" did you try spinning it over with the injectors out and into a bottle ??
These things run at a constant 20 plus PSI and it is varying of the duration of the injection time that controls fuel delivery
Did you do a Check of the TPS for its setting in case you kicked it by accident?

So IF you have tried all of the above ?? OR just want an Easy check ?

Unplug the Lamda ! Leave it unplugged and go for a ride !

I had quite a few of these do a sudden death thing !

Its Not "really" needed as the ECU will default to a slightly rich base map

I had one guy ran his 1150GSA like that because he didn;t want to pay for a replacement

 

[El Thermidor]

All to easy to dismiss the cable unseating from the inner end

Check that the throttle quadrants are stopping against their stop locations !

Explain as if attending the mechanic for the first time .............

What was the thing that you did immediately prior to the failure
Did you add fuel

Throttle bodies are both on their stops.

Not an air leak around the throttle bodies, I took an unlit blowtorch and gassed the outsides when idling, no rev change.

I hadn't run it in a few months, and its MOT was due, so I gave it an evening run across town: perhaps 6 miles each way, including some 60mph. It ran fine. A couple of days later I took it down to work - about a mile, it ran fine - and maybe 2 hours later went to take it to the test centre. Immediately that I started it it was running awfully. Thought maybe it just needed an Italian tune-up, but it wasn't even having that, popping, kangarooing down the road and stalling every few hundred yards. The fuel was old, yes, which is why I drained it, replaced the injectors and gave it 5l of super 98 to say sorry to it.

I've taken a video of it, what's the best way of uploading? Perhaps someone would hear the problem.

 

[El Thermidor]

https://imgur.com/a/9M2cHwK

Ok, lets see if this works...

You can hear it popping and spluttering, this is about as happy as it's been

 

[El Thermidor]

Did You have the tank lifted ? Charge battery? reconnect a wire?
Was it raining outside and you had it parked out there ?
Fuel "flow" may be more than needed "BUT" did you try spinning it over with the injectors out and into a bottle ??
These things run at a constant 20 plus PSI and it is varying of the duration of the injection time that controls fuel delivery
Did you do a Check of the TPS for its setting in case you kicked it by accident?

So IF you have tried all of the above ?? OR just want an Easy check ?

Unplug the Lamda ! Leave it unplugged and go for a ride !

I had quite a few of these do a sudden death thing !

Its Not "really" needed as the ECU will default to a slightly rich base map

I had one guy ran his 1150GSA like that because he didn;t want to pay for a replacement

As for the other items:

- Have now removed tank maybe 10 times, but nothing directly before the mot. Former me fitted a second QR to the fuel lines (reversed so they dont get mixed up!), which has been a lifesaver
- Yes, battery fully charged, using an optimate through the accessory socket
- No reconnected wires that I can think of, other than what I've replaced since the issue started. The oil pressure sensor appears to be on the blink, but that fails to 'no light' it would seem, and *shouldn't* be relevant
- Fuel lines pulled from injectors both sides, good solid fuel flow. Cycled multiple times to drain the new fuel before lifting tank each time
- Injectors checked and working, spray pattern onto cardboard checked
- TPS is solid, no movement, no evidence of past movement. Not sure how to check it as I don't have anything that can get to the pin while its connected
- I don't have a spare fuel pump flange o-ring and have a bitter memory of making a fuel-soaked one fit again, so I might have to order another one. I've already snapped one of the rivstuds, so im now looking for a tool and some spares

Sadly the emissions will be checked at the mot so I can't leave the lambda unplugged, but will try that now

 

[El Thermidor]

So IF you have tried all of the above ?? OR just want an Easy check ?

Unplug the Lamda ! Leave it unplugged and go for a ride !

I had quite a few of these do a sudden death thing !

Its Not "really" needed as the ECU will default to a slightly rich base map

I had one guy ran his 1150GSA like that because he didn;t want to pay for a replacement

Disconnected the lambda sensor, still running rough. Maybe even worse than before. Wouldn't fire on choke, with no choke it started.

I'm going to go back to the old injectors and see if it's any better.