Right side not firing. This is what I have tried:

[11101110]

Hello all,

 

I have been traveling for work way toooooo much and have only managed to get 400 miles on my bike in the last 12 months. I recently had it in my basement for a couple of months slowly working on the cruise control. Took it out today and found the right side cylinder not firing.

 

The right side exhaust is cold but the engine will run.

 

I have:

 

cleaned the injectors

Purged the fuel lines

verified spray from the injectors

swapped the injectors left to right

verified spark removed plug and grounded it, looks ok

ran the engine without a plug in the right.

new spark plugs

removed the coil to swap the plug wires.

 

none of this has solved the problem. I can start and run the engine but the right side lacks combustion. exhaust remains cold enough to hold even right at the block. I did get a backfire out of the injector port when I had the injector out.

 

There is no abnormal noise from the engine even on one cylinder. I am actually surprised how well it runs only on one cylinder.

 

I plan on pulling the cylinder cover tomorrow and check valve actuation. But may try swapping the plug wires to use a different side of the coil first.

 

Any suggestions on where to look next?

[ESokoloff]

My simular issue turned out to be sparkplug related.

 

See here.

[Tri750]

If the throttle cables are not seated firmly in the throttle bodies, meaning 1 (right side common) cable is sitting on top of the TB cable holder, the bike will seem to be on one cylinder.

 

IF your issue, sometimes you can whip the throttle wide open (engine not running) and let it snap shut and fix this.

Other times you have to use a long screwdriver snaked in to nudge the cable ferrul so it snaps in the TB sleeve.

If the throttle resistance is weak or wimpy, that's a good indicator that's the problem. Hope this helps.

[AndyS]

When you were working on the cruise control, is there any way you could have dislodged or removed the RHS HT lead from the coil?

 

Or

The electrical connection to the top of the RH Throttle Body?

[11101110]

When you were working on the cruise control, is there any way you could have dislodged or removed the RHS HT lead from the coil?

Even if I did when I removed the coil to swap the wires that would have solved any issue. After unscrewing the leads I did see that they were very clean at the contact area.

 

Or

The electrical connection to the top of the RH Throttle Body?

 

Are you referring to the injector wiring? The injector works still trying to get he gas smell off my leg.

[Tri750]

Cruise control ?

If you are installing a true electronic cruise, look at the cables as mentioned above.

[dirtrider]

Morning 11101110

 

[11101110]

Thanks TR750 and DR. That is what it was. I had removed the tank for a brake bleed before it left the basement and never noticed the cable had been pulled out of its seat in the adapter. I had checked and rechecked spark and fuel but never really thought of air. In my case too much air and in the waning daylight I never noticed this.

[dirtrider]

Thanks TR750 and DR. That is what it was. I had removed the tank for a brake bleed before it left the basement and never noticed the cable had been pulled out of its seat in the adapter. I had checked and rechecked spark and fuel but never really thought of air. In my case too much air and in the waning daylight I never noticed this.

 

Afternoon 11101110

 

That is one of the limitations of the BMW fuel injection system.

 

 

It (only) uses the L/H throttle angle (using the TPS or Throttle Position Sensor) to figure open loop fueling air flow. So basically it only fuels to the L/H side throttle opening.

 

If you have twice as much air entering the R/H cylinder then the fueling computer doesn't have a clue so only sends enough fuel based on the L/H side air requirements. (therefore a dead cylinder at idle on the R/H side)

[Tri750]

Back in the day, our dealership would use Electrical Splicing Tape to wrap around the cable and adjuster to secure the cables after a synch.

That stopped problems with the cables being dislodged.

We also saw (though rare) occasions where a small stone would get in there and prevent the TB from closing .