Quote:
Originally Posted by Johnston
When idling, the exhaust pipe from cylinder number 3 is considerably cooler than the other two.
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This cylinder is apparently not running at temperature. Here's my thought process, and maybe others will join in and expand on it:
There is a fuel air mixture contained in a closed cylinder which is then ignited. That seems like three variables to me - 1 is the fuel mixture, which of course has its own carb feeding it, so this would need to be checked, as mentioned by Scot. 2 is the ring and valves which keep the cylinder sealed, and can be checked with a cylinder pressure gauge or leakdown tester. Not likely with low miles, but not impossible either. 3 is the spark, and here your test results seem to widen the possibilities to something broader than just this one cylinder.
Quote:
Originally Posted by Johnston
I checked the spark on each of the cylinders, which gave a weird result. The spark on cylinders 2 and 3 is good, but I get little or no spark on cylinder 1.
I swapped the coils (1->2->3->1), but got the same result on the spark test and, when running the engine, the pipe from #3 is still cooler.
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Okay, cylinder 1 has an ignition issue, cylinder 3 is running cold, but cylinder 2 is just fine. Maybe this T-BIrd was a thumper in a past life
Sorry, back to the problem. Here's some ideas: maybe you have a bigger ignition problem that reveals itself at cylinder 1 all of the time, and cylinder 3 only when you are running the engine up at a higher rpm. You've found that cylinder 1 isn't getting the job done, but maybe #3 isn't either at speed, and this is why it is running cold. Possibility #2 is that you have two different problems which together give you the rough running and other symptoms. I would first eliminate the coils as a possibility, even given their low miles and relative youth. I have a perfectly good set of Gill coils that came off my Legend, and I would be happy to send them on loan for the cost of shipping. You could test your bike with these known good coils, and then send them back when you are finished. It would quickly eliminate at least one possibility from your plate. I have no knowledge of the ignitor beyond what I have read here, so maybe someone who has replaced theirs can chime in with whether or not this could also be the problem. I am assuming a bad ignitor would be across the board and not just specific to cylinders 1 and 3, but maybe I'm wrong on that.
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