Could improper mixture settings cause a miss?
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From: At my Bar drinking and wrenching in Lafayette Colorado
Re: Could improper mixture settings cause a miss? (JRChurch)
Rick -
I've never seen idle mixture or carb jetting actually cause a miss, unless you're running so rich that you're actually fouling plugs. You can get a rough idle if the mixture is off, and you can get a lack of performance at cruise and WOT, but I've never seen it actually cause a miss... I've also not had very good luck running Platinum plugs in the older cars.... a plain ol' set of Autolites seem to run much better. Good luck - hope the adjustment really fixed it for you! :cheers:
I've never seen idle mixture or carb jetting actually cause a miss, unless you're running so rich that you're actually fouling plugs. You can get a rough idle if the mixture is off, and you can get a lack of performance at cruise and WOT, but I've never seen it actually cause a miss... I've also not had very good luck running Platinum plugs in the older cars.... a plain ol' set of Autolites seem to run much better. Good luck - hope the adjustment really fixed it for you! :cheers:
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Joined: Feb 1999
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From: Fountain Hills AZ
Re: Could improper mixture settings cause a miss? (lars)
Lars, more good advise as usual but I'm unclear about one part. Other than the scenario you described where it fouls the plugs, how would the the idle mixture adjustment affect performance beyond idle?
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From: At my Bar drinking and wrenching in Lafayette Colorado
Re: Could improper mixture settings cause a miss? (Vetterodder)
Vetterodder -
Sorry I wasn't clear on that...
You're right - idle mixture will have little or no effect on anything off idle (cruise and WOT). The original question was whether or not improper mixture settings could cause a miss. What I meant was that improper idle mixture can cause a rough idle, whereas improper mixture at cruise and WOT can cause a lack of performance. Cruise and WOT mixtures are determined by jetting (main jet and rod sizes), and not by the idle mixture screws. In re-reading my post, I can see how it sounds like I implied that the idle mixture could affect poor performance at cruise and WOT. My mistake - I didn't mean that. Thanks for pointing it out to me!
Sorry I wasn't clear on that...
You're right - idle mixture will have little or no effect on anything off idle (cruise and WOT). The original question was whether or not improper mixture settings could cause a miss. What I meant was that improper idle mixture can cause a rough idle, whereas improper mixture at cruise and WOT can cause a lack of performance. Cruise and WOT mixtures are determined by jetting (main jet and rod sizes), and not by the idle mixture screws. In re-reading my post, I can see how it sounds like I implied that the idle mixture could affect poor performance at cruise and WOT. My mistake - I didn't mean that. Thanks for pointing it out to me!
