'85 w/460 gas rough idle, misfire
#1
'85 w/460 gas rough idle, misfire
Hi guys...new here, be easy on me LOL
I've got a F250 w/460 with a slight random misfire at low load (slow revving, ect) and idles like it's aggressively cammed. I've swapped plugs, wires, distributor, adjust timing, and cleaned the heck out of the carb but nothing changes at all. Compression is great, no vacuum leaks, and at WOT it performs great; it has only 90k total miles...
It's actually on it's 2nd carburator over the years (due to similar issues in the past causing it to fail Cali smog). This one is probably 12 years old. Luckily I'm in MD now so I don't have to worry about smog...I drove it all the way across the country with a huge trailer
Other than that the engine is 100% stock and body and interior are ****... even got a seat from a '94 F350
So are these carbs just crap? From what I'm reading you can't even adjust the mixtures. I REALLY want to get this thing running smoothly like it should..it really seems like the idle and low load mixture is way off..
I've got a F250 w/460 with a slight random misfire at low load (slow revving, ect) and idles like it's aggressively cammed. I've swapped plugs, wires, distributor, adjust timing, and cleaned the heck out of the carb but nothing changes at all. Compression is great, no vacuum leaks, and at WOT it performs great; it has only 90k total miles...
It's actually on it's 2nd carburator over the years (due to similar issues in the past causing it to fail Cali smog). This one is probably 12 years old. Luckily I'm in MD now so I don't have to worry about smog...I drove it all the way across the country with a huge trailer
Other than that the engine is 100% stock and body and interior are ****... even got a seat from a '94 F350
So are these carbs just crap? From what I'm reading you can't even adjust the mixtures. I REALLY want to get this thing running smoothly like it should..it really seems like the idle and low load mixture is way off..
#6
#7
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#8
It feels/sounds like a lean misfire but I don't have an A/F gauge to confirm. At WOT it is fine..plenty of power and no misfire.
#10
That would be my next check too. Here's a personal valuable tip: Screw the secondary idle screws in all the way with an Allen wrench then turn them back out exactly 1 turn. Make the final mixture adjustment with the primarys, trust me, it works.
#13
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