I have a 2003 250 hpdi (LZ250TXRB) that runs rough at idle. Otherwise it runs strong after putting it in gear and opening it up to wide open. It gets my boat (cobia 234 cc) up on plane in about 3 seconds.
On the ear muffs and garden hose, while idling, I pulled the spark plug wires off, one at a time. There was no change in the idle speed when the top left and middle right wires were pulled. (looking from stern to bow). I also tried a spark plug gap type tester on each plug wire. Again there was plenty of spark on all except the two mentioned above. There was no spark jumping across the gap until I got the contacts very close. At first , I thought it might be the plugs so I bought a new set of BKR6EKU's, but no change.
My question is: can ignition coils get weak at idle and then work at WOT ? It seems like it would be easy to replace the bad coils myself. Does the plug wire and cap come with the coil as a complete unit or do I have to order them separately as they have different part numbers on Yamaha parts list on your site? Also, the four top coils (two on each side part number 68F-82310-01-00) and the two bottom coils (one on each side part number 68F-82310-11-00) have different part numbers. Why is that ?
Any help would be appreciated. Thanks
Paul
On the ear muffs and garden hose, while idling, I pulled the spark plug wires off, one at a time. There was no change in the idle speed when the top left and middle right wires were pulled. (looking from stern to bow). I also tried a spark plug gap type tester on each plug wire. Again there was plenty of spark on all except the two mentioned above. There was no spark jumping across the gap until I got the contacts very close. At first , I thought it might be the plugs so I bought a new set of BKR6EKU's, but no change.
My question is: can ignition coils get weak at idle and then work at WOT ? It seems like it would be easy to replace the bad coils myself. Does the plug wire and cap come with the coil as a complete unit or do I have to order them separately as they have different part numbers on Yamaha parts list on your site? Also, the four top coils (two on each side part number 68F-82310-01-00) and the two bottom coils (one on each side part number 68F-82310-11-00) have different part numbers. Why is that ?
Any help would be appreciated. Thanks
Paul
Comment