another egine miss

buzzinhalfdozen · 06-29-2012, 10:15 AM

Randy I'm not familiar with the Mallory stuff, however I would assume that it would work . The "box" is simply looking for a trigger input. What is your battery voltage doing when it acts up? Is it stable, is it above 11.9 volts? BTW you stated that "the computer showed it" (the miss) how exactly did you see the miss? The fact that the tach jumps around when the miss is there would indicate that 1, the tach could be the trouble,2 the "box" is recieving undesired triggers, which causes it to lose track of when to trigger the coil. I would simply hook up my MSD tester to the crank trigger connector and spin it up, by doing so you can ensure the box and coil are OK. What sort of airgap do you have on the crank sensor? Too wide tends to cause issues, over .060 seems to be the limit, also crank wheel runout can cause the same thing, is the crank wheel running true? Please let us know what you find out, as we seem to have a few strange misses going on this forum with no fixes yet. Good luck Joe afew things to consider also, if you purchase a new crank sensor please consider getting the "shielded" sensor. This has fixed more than 1 car that I know of. Also is the miss RPM sensitive...does it start at a given RPM?

06-29-2012, 10:15 AM	#11
buzzinhalfdozen Senior Member Join Date: Sep 2006 Location: Bellevue Ohio Posts: 984 Likes: 0 Liked 11 Times in 8 Posts	Re: another egine miss Randy I'm not familiar with the Mallory stuff, however I would assume that it would work . The "box" is simply looking for a trigger input. What is your battery voltage doing when it acts up? Is it stable, is it above 11.9 volts? BTW you stated that "the computer showed it" (the miss) how exactly did you see the miss? The fact that the tach jumps around when the miss is there would indicate that 1, the tach could be the trouble,2 the "box" is recieving undesired triggers, which causes it to lose track of when to trigger the coil. I would simply hook up my MSD tester to the crank trigger connector and spin it up, by doing so you can ensure the box and coil are OK. What sort of airgap do you have on the crank sensor? Too wide tends to cause issues, over .060 seems to be the limit, also crank wheel runout can cause the same thing, is the crank wheel running true? Please let us know what you find out, as we seem to have a few strange misses going on this forum with no fixes yet. Good luck Joe afew things to consider also, if you purchase a new crank sensor please consider getting the "shielded" sensor. This has fixed more than 1 car that I know of. Also is the miss RPM sensitive...does it start at a given RPM? __________________ Joe Buchanan SS/BX 3117 Last edited by buzzinhalfdozen; 06-29-2012 at 10:18 AM.