help,running on one cylinder

13-02-2009, 05:53 PM

I just had my tank off to do some tinkering on my 1999 900 now put it all back and only running on one cylinder . Any ideas ? what can I check
Thanks
Johnny

14-02-2009, 12:16 AM

have you got spark?is it good?try swapping the plugs around,if it cures it you've got the offender. obvious stuff is the HT lead up to the coil and the coil itself.

14-02-2009, 07:29 AM

Are the coils under the tank on that model?

If so, you may have "tinkered" one of the coil wires off it's connector - check both the coils to make sure they look the same - IE they both have the same number of wires connected to them etc.

14-02-2009, 11:32 AM

Quote:

Originally Posted by johnny fontana

I just had my tank off to do some tinkering on my 1999 900 now put it all back and only running on one cylinder . Any ideas ? what can I check
Thanks
Johnny

Thanks guys, just checked the plug, plug cap, HT lead coils,pick up coils etc and they all checked out ok. started it again and now its ok !!! Whats that all about ?? must be a dodgy connection somewhere. Bloody wiring. I think thats the only thing that lets monsters down
Johnny

14-02-2009, 11:55 AM

don't want to sound funny but maybe the plug not fully inserted in the cap,thus giving a weak spark

14-02-2009, 01:54 PM

mine does this every 2-3 months and buying new plugs always does the trick

14-02-2009, 11:16 PM

try buying irridium plugs - a bit more expensive but they last a lot longer

15-02-2009, 12:47 PM

Quote:

Originally Posted by snakey

try buying irridium plugs - a bit more expensive but they last a lot longer

The plug is fine, I have this gadget that you put between the plug and cap and shows you the spark. when I had the problem there was a very weak spark, after doing all the checks as it tells you in the haynes manual ie coil and pick up coil resistance, plug lead and cap etc it then started fine. I can only guess it was a bad connection which is worrying as I have know idea what it was.
Thanks
Johhny

15-02-2009, 01:29 PM

Those spark checker tools only show that the power is going to the plug - but they dont show that it is sparking!
If the plug is very wet with fuel the spark seems to track across the wet surface. Try replacing it with a dry plug and see if that works.

If the battery is low and the oil is thick (cold weather) mine sometimes wets a plug and only one pot fires then it won't go onto 2 cylinders till i take out the wet one and dry it.
You can tell which one is wet because that cylinder is cold.

I am sure that iridium plugs will fix it but i am too lazy/tight to buy them

Jon

13-02-2009, 05:53 PM	#1
johnny fontana Guest Posts: n/a	help,running on one cylinder I just had my tank off to do some tinkering on my 1999 900 now put it all back and only running on one cylinder . Any ideas ? what can I check Thanks Johnny

15-02-2009, 01:29 PM	#9
lcjohnny Guest Posts: n/a	running on one Those spark checker tools only show that the power is going to the plug - but they dont show that it is sparking! If the plug is very wet with fuel the spark seems to track across the wet surface. Try replacing it with a dry plug and see if that works. If the battery is low and the oil is thick (cold weather) mine sometimes wets a plug and only one pot fires then it won't go onto 2 cylinders till i take out the wet one and dry it. You can tell which one is wet because that cylinder is cold. I am sure that iridium plugs will fix it but i am too lazy/tight to buy them Jon

14-02-2009, 12:16 AM	#2
Pomp1 Guest Posts: n/a	have you got spark?is it good?try swapping the plugs around,if it cures it you've got the offender. obvious stuff is the HT lead up to the coil and the coil itself.

14-02-2009, 07:29 AM	#3
Trent Guest Posts: n/a	Are the coils under the tank on that model? If so, you may have "tinkered" one of the coil wires off it's connector - check both the coils to make sure they look the same - IE they both have the same number of wires connected to them etc.

14-02-2009, 11:55 AM	#5
Pomp1 Guest Posts: n/a	don't want to sound funny but maybe the plug not fully inserted in the cap,thus giving a weak spark

14-02-2009, 01:54 PM	#6
julesbristol Guest Posts: n/a	mine does this every 2-3 months and buying new plugs always does the trick

14-02-2009, 11:16 PM	#7
snakey Guest Posts: n/a	try buying irridium plugs - a bit more expensive but they last a lot longer