'94 K1100LT Cured my ABS issues, but am I looking at breather issues or bad HES?

Hello, all....

My until-now trusty 94 K1100LTSE (58K miles) has just begun stumbling after running 50 miles or so. I recently won the battle of bringing the ABS back to life, but during the proof-of-principle test ride through rural Maryland, rolling on the throttle resulted in a sudden roughness, with a return of power after rolling it back. The engine remained rough-running until shutdown, and after replacing my fuel filter, it ran ok .... until I pulled off a long straight and was proceeding up a secondary hill in 3rd gear. Problem same as before.

I remembered the tech at Bob's in Balto observing that my breather return was oily, which I did nothing about at the time. I have a new breather tube on order, but after a fairly thorough look at various forums, I think I am looking at a complex fault tree to sort through.

That said, I want to cut to the chase in the most efficient and inexpensive manner.

My plugs were recently renewed, new air filter before parking last season, and I am now running a tank of techron-enhanced goodness.

What would the collective Brick Universe do now?

greetings...

the first thing i would do is uncouple the 4 pin under tank connector that goes from the wiring harness to the fuel pump...

make sure the connector is clean and free from corrosion and the wiors are tight...

then i would recouple it and give it a go...

could getts lucky and not have to mess with anything else...

j o

Done did.... but a redo is cheap.

owrstrich said:

greetings...

the first thing i would do is uncouple the 4 pin under tank connector that goes from the wiring harness to the fuel pump...

make sure the connector is clean and free from corrosion and the wiors are tight...

then i would recouple it and give it a go...

could getts lucky and not have to mess with anything else...

j o

Click to expand...

Thanks...

I have sampled that low-hanging fruit. Just came back from test ride 2, and it didn't stumble until I decided to head toward the barn... Murphy lives. Next, I plan to drain the tank and check the fuel pump wires.

Maybe dirty injector...

ChicagoGeo said:

Thanks...

I have sampled that low-hanging fruit. Just came back from test ride 2, and it didn't stumble until I decided to head toward the barn... Murphy lives. Next, I plan to drain the tank and check the fuel pump wires.

Click to expand...

I am now holding my breath. Last ride went better, with doses of isoHEET and Seafoam in the tank. It's been hot here, so maybe it isn't the HES after all.

Sounds a lot like an air leak in the vacume hose connections.....Possibly one of the hoses is detached slightly or cracked allowing a loss of vacume. Could even be the rubber on the throttle bodies at this age.....Breather tube being oily often means it is cracked and the oily vapors are venting, and you are loosing some of the vacume that sucks those vapors down into the throttle bodies from the back side. I never experienced the issues you describe when my breather hose was split (bad enough oil was pooling and running off the back side of the engine onto my left boot....), but that does not mean you wouldn't. When you do the breather hose replacement, check the connection of all those little hoses and ensure they are snug after you complete all your work.

ChicagoGeo said:

I am now holding my breath. Last ride went better, with doses of isoHEET and Seafoam in the tank. It's been hot here, so maybe it isn't the HES after all.

Click to expand...

If the HEET helped, it sounds like water in the gas.

Additives hopefully don't make it any worse...

98lee said:

If the HEET helped, it sounds like water in the gas.

Click to expand...

I am down to either the breather system, plug wires or voodoo. Stumbling is presently almost a dead miss. I hope I don't get stranded at the salt mine!

Next installment in the saga.

ChicagoGeo said:

I am down to either the breather system, plug wires or voodoo. Stumbling is presently almost a dead miss. I hope I don't get stranded at the salt mine!

Click to expand...

Latest update...Spent a pleasant day pulling the tank and going over stuff under it and inside the relay box, checked the plug wire resistances (all 5Kohms +/-), cleaned several connectors, (some again for the umpteenth time). I discovered why my front position lights were only turn signals, which is another story. (a bare plug in the relay box that traced to the socket. Something missing after a conversion to red LED lights in the rear ones?)

I digress..

A very promising test ride was had.

However, on the short hill two blocks from my house, which I often take "at the speed limit," the starved-for-gas condition reappeared. I plan to redo the tank connector and maybe put a fuel pressure gauge in line just for grins.

Breather Issues, indeed.

Solved it. Spend the weekend tearing the bike apart, installing the new rubber tubing bits.

When hearing hooves, I guess I may have been expecting Zebras.

All seems OK now, but decided take the conservative approach and not add the 'special second vacuum manifold' as has been mooted by others. (The local auto emporiums were poorly stocked with small such parts.)

The next step will be balancing the idle, but I can live with it.

Back to square one?

ChicagoGeo said:

Solved it. Spend the weekend tearing the bike apart, installing the new rubber tubing bits.

When hearing hooves, I guess I may have been expecting Zebras. ...
QUOTE]

OK, this sounds like a soliloquy now...

Same test ride, great expectations of success. Same spot on the ride, uphill under acceleration, same problem, only worse this time.

BIG stumble with more throttle. I think I have cured whatever vacuum leaks I thought I had. After the problem resurfaced, I kept going through a few twisties, and, of course, the bike ran like a champ on the freeway on the straight path home, at the usual ambient speed, with lots of juice left.

What the heck???

Click to expand...

Never trust a 'pulled' fuel filter...

ChicagoGeo said:

ChicagoGeo said:

BIG stumble with more throttle. I think I have cured whatever vacuum leaks I thought I had. After the problem resurfaced, I kept going through a few twisties, and, of course, the bike ran like a champ on the freeway on the straight path home, at the usual ambient speed, with lots of juice left.

What the heck???

Click to expand...

I am pretty sure I have finally won! Spent a pleasant day cleaning every harness I could find and installed a FRESH fuel filter. Bike is now running like a champ, and hasn't hiccupped in 60 miles, at least.

All the stuff I did had to be done anyway...
I hope nobody takes umbrage at the extravagant use of bandwidth!

Click to expand...