Plugged fuel filter?

[Patriot]

Radio,
Rats! I thought the wiring harness would have been the magic bullet....well one less thing on you list and at least it did need some service. Sure it will run better when this heat situation clears.

Hope you find the culprit soon.

+1

watching this scenero unfold at the edge of my seat sending up best wishes and prayers for a quick and complete understanding of the problem(s) and repair

go Howie, rah rah rah !!!

 

[dcarver]

Hey Howie, move to Alaska! :****:

 

[radman]

Curious, the temperature thing.... 3 bars and whammo? ECU getting false, out of range ambient temp sensor value? Does the ambient temp indicator also feed the ECU? If so, what does it read when the buck snorting start? Probably not it, but all brainstorming ideas may lead to solutions..

Worse that could happen with a bad temp sensor would be

1) it reads hot so cold start is a problem

2) reads cold so that hot driveability is a problem.

Neither will keep a motor from revving. Either no or difficult cold start, or rich as a ***** warm running, but neither would cause the complaint. The hot failure is the key-and there are a couple components that

1) will not set a code or trigger limp mode (computer substitutes known good values yet allows continued running)

2) have a history of failure based on temperature-

 

[odot]

open circuit, closed circuit?

 

[radman]

open circuit, closed circuit?

Keeps running though. Won't rev. Need to slap a fuel pressure gauge on this bike first thing. Ever run this thing outta gas RH?

 

[odot]

You saying that fuel tank drain will keep it running through fuel injectors?

 

[radman]

You saying that fuel tank drain will keep it running through fuel injectors?

No, I'm saying a reduction in fuel pump pressure/flow will cause problems just like he's having. But then quite a few components will-it's a matter of eliminating possibles one by one until the cause is found. The hot only pretty much dismisses a FP regulator problem, and points more toward fuel pump failure. Not plugged, but actually not being able to keep pressure up. Mopar mini vans would do this-run fine, get warm, slow, fail. Cool down, run ok, get warm, fail. Had one that went 50 miles this way, and eventually got to a repair facility under it's own power-but took 3 hours to do it.

 

[mcatrophy]

...The engine heat is definitely the key, because it does crank, idle and run perfectly until up to full operating temp. And so far, it hasn't been prudent to pull over and start running diags in the dark.

...

RH - Did you ever check or change your spark plugs? I can't see you saying you've done so - unless I'm blind :bigglasses: .

Could possibly cause the symptoms.

 

[odot]

Ok...air leak in fuel supply. Not fuel coming out, but, air coming in.........

 

[radman]

Ok...air leak in fuel supply. Not fuel coming out, but, air coming in.........

Hence the fuel pressure gauge-reads low or variable, closer to discovery.

 

[odot]

It's more then a long shot as this would only occur at the injector itself. And I doubt that all or more then one would be intaking air.

 

[radman]

Yup. I doubt dirt or other blockage is involved-the off-on nature of the problem discourages that thought, though nothing is impossible. But a failing fuel pump could/will cause exactly these symptoms-so pump must be checked to either confirm as the cause-or dismiss, so it can be checked off the list. Now you guys know why auto/bike repair can cost so much when a clear failure hasn't presented itself. The good part? Each step gets one closer to THE ANSWER

 

[odot]

I wonder how much fuel the moron has in his tank?

 

[Geezer]

You saying that fuel tank drain will keep it running through fuel injectors?

No, I'm saying a reduction in fuel pump pressure/flow will cause problems just like he's having. But then quite a few components will-it's a matter of eliminating possibles one by one until the cause is found. The hot only pretty much dismisses a FP regulator problem, and points more toward fuel pump failure. Not plugged, but actually not being able to keep pressure up. Mopar mini vans would do this-run fine, get warm, slow, fail. Cool down, run ok, get warm, fail. Had one that went 50 miles this way, and eventually got to a repair facility under it's own power-but took 3 hours to do it.

Yes, my kid's Pontiac GrandAm had that problem. It would run fine for a while, sometimes an hour or more, then just refuse to rev and eventually wouldn't go at all. Let it cool off and it would run for a while. It took a long time to diagnose, but a new fuel pump fixed it.

 

[RadioHowie]

open circuit, closed circuit?

Keeps running though. Won't rev. Need to slap a fuel pressure gauge on this bike first thing. Ever run this thing outta gas RH?

No

 

[RadioHowie]

Ok...air leak in fuel supply. Not fuel coming out, but, air coming in.........

If there was a way for air to get in, wouldn't it make sense that fuel would run out the entry point?

The fuel IS under pressure....probably a bit more than the 14 psi of atmospheric.

IF there was an air leak in the fuel system, then fuel would be spraying out of it like a firehose, wouldn't it?

 

[Bustanut joker]

I'm gonna venture the ECU is faulty....

:jester:

 

[RadioHowie]

I wonder how much fuel the moron has in his tank?

Yeah, right. AND I suppose you think there should be oil in the crankcase as well.

Fookin' *****!

I bet there's more fuel in my tank then there are gray cells in your skull.

 

[Bustanut joker]

I wonder how much fuel the moron has in his tank?

Yeah, right. AND I suppose you think there should be oil in the crankcase as well.

Fookin' *****!

I bet there's more fuel in my tank then there are gray cells in your skull.

Man, I'm all over that bet. Howies side of course B)

:jester:

 

[RadioHowie]

...The engine heat is definitely the key, because it does crank, idle and run perfectly until up to full operating temp. And so far, it hasn't been prudent to pull over and start running diags in the dark.

...

RH - Did you ever check or change your spark plugs? I can't see you saying you've done so - unless I'm blind :bigglasses: .

Could possibly cause the symptoms.

You didn't miss it 'cause I never mentioned it, but Feej has new NGKs. Them ain't the problem.

Had a little time to continue "the search" tonight. Pulled the T-Bar to check the plugs. Damn, that #2 plug boot's hard to get out. Plugs are fine, a little darker than a George Hamilton tan. More like a Halle Barry mocha. Not surprising they don't look "perfect" since it is running fooked. Checked that all the plug wires were screwed tight in the boots. All okay. No corrosion in the boots or on the plugs. Shot a little cleaner in there just for the halibut. Took her out for a spin. Again, runs like a ***** ape until it's warmed up enough to cycle the fan, then all goes to hell.

As previously mentioned, a TPS recall is set for Tuesday. I'm gonna have the shop do a fuel pressure test while the tank's up. Let's try to pinpoint a fuel pump problem. Hope not. $435.00 not counting labor would be an awfully bitter pill to swallow.