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</o:shapelayout></xml><![endif]--></head><body lang=EN-AU link="#0563C1" vlink="#954F72" style='word-wrap:break-word'><div class=WordSection1><p class=MsoNormal><span style='mso-fareast-language:EN-US'>Hello Mike<o:p></o:p></span></p><p class=MsoNormal><span style='mso-fareast-language:EN-US'><o:p> </o:p></span></p><p class=MsoNormal><span style='mso-fareast-language:EN-US'>I had a similar situation in the BN3.<o:p></o:p></span></p><p class=MsoNormal><span style='mso-fareast-language:EN-US'><o:p> </o:p></span></p><p class=MsoNormal><span style='mso-fareast-language:EN-US'>Tuned and reset everything multiple times and it just wouldn’t go away.<o:p></o:p></span></p><p class=MsoNormal><span style='mso-fareast-language:EN-US'><o:p> </o:p></span></p><p class=MsoNormal><span style='mso-fareast-language:EN-US'>After some weeks, eventually tracked the problem to the modern inline fuel filter that I had installed. Went back to how it left the Donald Healey Motor Company and problem disappeared.<o:p></o:p></span></p><p class=MsoNormal><span style='mso-fareast-language:EN-US'><o:p> </o:p></span></p><p class=MsoNormal><span style='mso-fareast-language:EN-US'>Hoo Roo<o:p></o:p></span></p><p class=MsoNormal><span style='mso-fareast-language:EN-US'><o:p> </o:p></span></p><p class=MsoNormal><span style='mso-fareast-language:EN-US'>Patrick Quinn<o:p></o:p></span></p><p class=MsoNormal><span style='mso-fareast-language:EN-US'>Blue Mountains, Australia<o:p></o:p></span></p><p class=MsoNormal><span style='mso-fareast-language:EN-US'><o:p> </o:p></span></p><div style='border:none;border-top:solid #E1E1E1 1.0pt;padding:3.0pt 0cm 0cm 0cm'><p class=MsoNormal><b><span lang=EN-US>From:</span></b><span lang=EN-US> Healeys <healeys-bounces@autox.team.net> <b>On Behalf Of </b>Michael Salter<br><b>Sent:</b> Thursday, 29 September 2022 8:25 AM<br><b>To:</b> healeys@autox.team.net<br><b>Subject:</b> [Healeys] Austin Healey 100 Misfire Diagnosis.<o:p></o:p></span></p></div><p class=MsoNormal><o:p> </o:p></p><div><div><p class=MsoNormal style='margin-bottom:8.0pt;line-height:106%'>This problem has plagued me for over 1000 miles.<o:p></o:p></p><p class=MsoNormal style='margin-bottom:8.0pt;line-height:106%'>Today I had to drive some 200 miles and this is how it went:<o:p></o:p></p><p class=MsoNormal style='margin-bottom:8.0pt;line-height:106%'>Starting from cold I experienced a persistent and irregular misfire. <o:p></o:p></p><p class=MsoNormal style='margin-bottom:8.0pt;line-height:106%'>Pulling the choke out made no perceivable difference.<o:p></o:p></p><p class=MsoNormal style='margin-bottom:8.0pt;line-height:106%'>Power was not much affected and the car cruised along well in top overdrive with just regular periods of misfiring.<o:p></o:p></p><p class=MsoNormal style='margin-bottom:8.0pt;line-height:106%'>Climbing slopes really made no difference, even when full throttle was applied for 10 - 15 seconds.<o:p></o:p></p><p class=MsoNormal style='margin-bottom:8.0pt;line-height:106%'>Misfire continued for some 90 miles with no change when the engine was fully heated up.<o:p></o:p></p><p class=MsoNormal style='margin-bottom:8.0pt;line-height:106%'>I could really do nothing to influence the rate of the misfire although it did seem to be slightly less evident at low throttle settings.<o:p></o:p></p><p class=MsoNormal style='margin-bottom:8.0pt;line-height:106%'>After 90 miles I stopped briefly to get fuel and upon starting off it was quite evident that the misfire had disappeared almost completely and remained that way for at least 80 miles after which it started to misfire just a little as I came to the end of the trip.<o:p></o:p></p><p class=MsoNormal style='margin-bottom:8.0pt;line-height:106%'><u> POSSIBLE CAUSES</u><o:p></o:p></p><p class=gmail-msolistparagraph style='mso-margin-top-alt:0cm;margin-right:0cm;margin-bottom:0cm;margin-left:36.0pt;line-height:106%'>1.<span style='font-size:7.0pt;line-height:106%;font-family:"Times New Roman",serif'> </span>Plugs … not like a bad plug. The misfire seems to be more than 1 cylinder and never came close to being the regular beat that 1 plug misfiring produces. All the plugs have a healthy brown/ grey appearance.<o:p></o:p></p><p class=gmail-msolistparagraph style='mso-margin-top-alt:0cm;margin-right:0cm;margin-bottom:0cm;margin-left:36.0pt;line-height:106%'>2.<span style='font-size:7.0pt;line-height:106%;font-family:"Times New Roman",serif'> </span>Coil … In my experience coils are very reliable but when they do fail they tend to fail as they warm up and the problem gets worse as the coil warms up<o:p></o:p></p><p class=gmail-msolistparagraph style='mso-margin-top-alt:0cm;margin-right:0cm;margin-bottom:0cm;margin-left:36.0pt;line-height:106%'>3.<span style='font-size:7.0pt;line-height:106%;font-family:"Times New Roman",serif'> </span>Points … a possibility but the dwell is set at exactly 60 degrees and does not waver at all when the engine is running in the shop.<o:p></o:p></p><p class=gmail-msolistparagraph style='mso-margin-top-alt:0cm;margin-right:0cm;margin-bottom:8.0pt;margin-left:36.0pt;line-height:106%'>4.<span style='font-size:7.0pt;line-height:106%;font-family:"Times New Roman",serif'> </span>Fuel pump … if the engine was starving for fuel because of a fuel supply issue caused by a blockage or failing pump the problem would get worse when the demand for fuel increased, as in climbing a hill of full throttle. This was absolutely not the case.<o:p></o:p></p><p class=gmail-msolistparagraph style='mso-margin-top-alt:0cm;margin-right:0cm;margin-bottom:8.0pt;margin-left:36.0pt;line-height:106%'><o:p> </o:p></p><p class=gmail-msolistparagraph style='mso-margin-top-alt:0cm;margin-right:0cm;margin-bottom:8.0pt;margin-left:36.0pt;line-height:106%'>Any ideas folks?<o:p></o:p></p><p class=gmail-msolistparagraph style='mso-margin-top-alt:0cm;margin-right:0cm;margin-bottom:8.0pt;margin-left:36.0pt;line-height:106%'><o:p> </o:p></p></div></div></div><div id="DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2"><br /><table style="border-top: 1px solid #D3D4DE;"><tr><td style="width: 55px; padding-top: 13px;"><a href="https://www.avast.com/sig-email?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_content=emailclient" target="_blank"><img src="https://s-install.avcdn.net/ipm/preview/icons/icon-envelope-tick-round-orange-animated-no-repeat-v1.gif" alt=" width="46" height="29" style="width: 46px; height: 29px;"/></a></td><td style="width: 470px; padding-top: 12px; color: #41424e; font-size: 13px; font-family: Arial, Helvetica, sans-serif; line-height: 18px;">Virus-free.<a href="https://www.avast.com/sig-email?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_content=emailclient" target="_blank" style="color: #4453ea;">www.avast.com</a></td></tr></table><a href="#DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2" width="1" height="1"> </a></div></body></html>