Revs going up and down like a mad woman's knickers ?

[bobsnew]

I replaced the hall sensor a week ago with a second hand unit after mine failed, Ran fine for 200 miles, also replaced all 4 Plugs (twin Spark) 2005 GSA, started playing up on Sunday at the end of a 100 mile run, misfiring rev counter going from 3500 to 1000 cutting out on me, eventually got home riding the clutch keeping throttle open.
I have tested both the old and new HES, the old one showed a fault on the lower switch, however when i warmed the unit up on a radiator overnight, the switch showed working. Swapped over the HES from new to old, old unit wouldn't run, new one showing no fault on LED tester but will idle at 1000 revs as soon as you give it throttle 2000 to 3500 revs, it goes crazy again.
Any thoughts on the subject please

 

[magicstu]

I've had no experience on these sensors,so i'm up for being called a muppet and such like..
Is it worth checking the wiring from the sensor to the main loom/plug, if all the signs point to the sensor faulty,and it tests OK,that's where i would have the first nose around, or maybe a reset is needed ?

 

[bobsnew]

Reset

Hi I have checked the connection plug into the main loom as best as I can, when you mention a reset, what exactly is meant ?

 

[Welshman]

Check your TPS plug connection and voltage?

 

[Vern]

You haven't just bought a new duff set have you?

Any cracks or debris stuck to the magnets at all?

 

[AndrewD]

Though about air leaks leaning the mix?

Run it and spray water around the TB's to see if it settles down. I take it you've checked the little rubber plugs are on the bleeds etc?

 

[bobsnew]

Dont know the answer

Still mystified what caused the problem, but i seem to have solved the problem, took tank off, Pushed and pulled all the electrical plugs and sprayed them with electrical cleaner solvent, took off ECU and pushed it back on, immediately fired up, running sweetly now, frustrating thing Is I don't know what caused it ?
Does anyone know if there is a process for resetting the ECU once a fault is shown, I may have inadvertently reset something, haven't a clue but a happy bunny now.

 

[AndrewD]

Still mystified what caused the problem, but i seem to have solved the problem, took tank off, Pushed and pulled all the electrical plugs and sprayed them with electrical cleaner solvent, took off ECU and pushed it back on, immediately fired up, running sweetly now, frustrating thing Is I don't know what caused it ?
Does anyone know if there is a process for resetting the ECU once a fault is shown, I may have inadvertently reset something, haven't a clue but a happy bunny now.

Worth going through the HES, Lambda, TPS and ECU plugs, I know the ECU gets a bit sweaty and a bit of ACF50 spray will keep it at bay. Few mins at home is better than a ball ache on the road!

 

[bobsnew]

Thanks

I appreciate the advice given, no comments regarding resetting the ECU so I take it thats unheard of ?
I have given it a 50 mile ride today and it behaved impeccably, i have been quite generous with WD 40 on connections, fingers crossed, i am assuming it was a dodgy connection, frightening experience though I dont wish to repeat.

 

[sethmopp]

I had something like this a while back, it turned out to be the positive teminal to the battery being a little loose, but gave the same symptoms as HES trouble, I have a spare one just in case though.....

 

[bobsnew]

electrical connections

No Battery was tight, but I pulled off all the connection plugs I could find and gave them a spray of Trichloroethene, hey presto all is working well, though I intend to build a new HES if I get a couple of donor parts.