running bad (feeling blessed)...limped home (walking on air)

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Patriot

Isabella is Lazarus
Joined
Dec 2, 2008
Messages
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Location
Metairie, LA suburb of Ole Nawlins'
so, another saga of isabella's misbehaving is as follows:

riding home from round trip day of 275miles, humming away on the interstate with AVCC set to 75 and near my home, I see the bike laboring and losing speed on overpass hills that normally are no problem. As I approach my exit, I pull in clutch and engine kills...will not idle; won't run below 2000 rpms

So limp home last few miles and pull into garage. A little later, try to start it...takes like a bunch of throttle, it runs, but no idle and wants to kill below 2000 rpm.

Next day when cold, I raise tank...looking around, don't see anything out of ordinary like damage wiring or plugs, vac hose disconnected, etc. With trepidation, I pulled the plugs, and without a compression tester, sealed each hole with my hand/fingers, and hand was "puffed" off and away. Then I check that each plug was firing by connecting to the wire and grounding to valve cover, spinning the engine.

So now what? Gee, could the cam chain had jumped a tooth...have no idea why as it's the new CCT since the valves were checked. This engine has 70k miles with valve check at 55k and no adjustment needed.

I guess I really do need to do a proper compression check with gauge...

depressed in Nawlins'

Mike da Patriot

<appropriate pissed off smiley>

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Sooooo, your new cct was saying to your engine..."...and I was like just fine before he started messing with me" and your engine was saying to the cct..."...and I was like just fine before he put spacers on my valves, I mean...what was he thinking?....I was like, no way, dude.....I'm fine.....just gag me with a spoon why don't you?".

I can't imagine what your cam was saying to your chain other then....."I was like....whatevs......".

Sorry, dude....you do have good gas in there, right?

 
Which hole did that funky looking plug come out of, or does the pic make it look worse than actual?

Is the engine missing?

--G

 
Why is there oil on your plugs threads?

Bad gas? When was the last time you filled up?

Vacuum leak? Check all your vacuum lines and your AVCC hook-up.

Probably just something simple.

 
Why is there oil on your plugs threads?
Bad gas? When was the last time you filled up?

Vacuum leak? Check all your vacuum lines and your AVCC hook-up.

Probably just something simple.
that's "never seize" on threads

fueled up 100 miles before problem same afternoon

AVCC works fine

I have no idea how many or where vac lines are...

PAIR is removed with holes plugged (where WinPro plates would go if I had them)...

at least one hose to the left has a plug in it...

mechanic who swapped engine removed it all

 
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Were two of the plugs darker? If so, maybe one of the coils has crashed. i couldn't tell if only one was discolored or two. Just a guess.

One coil supplies voltage to cylinder 1 and 4, the other to 2 and 3.

 
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Maybe take off all the accessories and return to stock...see if that helps. :0

(No..that's just mean)

Sorry about your troubles, hope it all gets sorted out soon.

 
I agree with vacuum. Check all plugs and nipples where the secondary air and TBS leads attach, and make sure the cruise control vacuum lines are good. Bad gas shouldn't show up at the end of a trip unless it was just after a fill-up.

A bad crank position sensor or damaged wire that comes around the timing cover can do similar things. Make sure that wire didn't get pinched when you reassembled after doing the CCT.

 
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One obvious place to look for a vacuum leak is the four hoses you disconnect for a TBS. It would be easy to see if one of them has come loose from the throttle body.

However, my SWAG is bad fuel.

 
Mike,

Did you try starting it cold?

The reason I ask is because your symptom sounds a lot like what happens when the TPS goes bad. Runs like crap and won't idle when hot. Magically works fine when cold.

Good luck in your troubleshooting

 
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Just an idea.

I had almost the same problem last Fall. Bike stalled turning on to an off-ramp (luckily down hill). Eventually it re-started, but wouldn't run under 2,000 rpm. It was pissing rain so I limped home and parked the bike in my shop to dry off. Same situation next morning. I remembered reading an old post https://www.fjrforum.com/forum//index.php/topic/22734-main-ecu-connector-contamination/?do=findComment&comment=268059 , lifted the tank and found the connectors were green with corrosion. Cleaned them and sealed with dialectric grease, re-started the bike - no more problem!

Al.

 
My #1 guess would be a vacuum leak somewhere.

My #2 guess is:

I had a similar poor running issue after a CCT replacement. Although it was not proven beyond any doubt, it is believed that the performance issues were related to an oxygen sensor wire pinched between the case and the timing cover. Insulation was split allowing the sensor to ground to the chassis giving a false reading.

 
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