Carb swap guys, help!
11-07-2011, 08:19 AM
#24
Did you buy that engine running? I had a similar issue with it back firing and turned out I had a bent valve. You should do a compression check on all cylinders. Eliminate the engine being the problem, you have eliminated the carb so now work on the compression test. If all cylinders are ok, I would lean towards an electronic issue.
11-10-2011, 09:51 AM
#26
TECH Junkie
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Ok u switched carbs (helped)
Check coils (fine)
Timing (Ok)
Spark plugs (?)
Sprak plug gaps (?)
Sprak Plug wires(?)
MSD connections from box to coil (checked)
Vacuum leak (checked)
Compression (checked)
MSD Ground good (?)
Fuel Pressure settings(?)
Type and Age of Springs(?)
Maybe answer the ?'s can help narrow down the cause
Check coils (fine)
Timing (Ok)
Spark plugs (?)
Sprak plug gaps (?)
Sprak Plug wires(?)
MSD connections from box to coil (checked)
Vacuum leak (checked)
Compression (checked)
MSD Ground good (?)
Fuel Pressure settings(?)
Type and Age of Springs(?)
Maybe answer the ?'s can help narrow down the cause
11-11-2011, 11:10 PM
#27
Launching!
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My 6012 box adds the MAP timing to the base timing...even w/o a map sensor connected...so I was getting an extra 20* of timing I didn't need. Are you leaving a laptop hooked up so you can see what your timing is actually doing at idle?
11-15-2011, 11:59 AM
#28
Staging Lane
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Ok u switched carbs (helped)
Check coils (fine)
Timing (Ok)
Spark plugs (?)---------have swapped them 4 times
Sprak plug gaps (?)-----as out of the box, honestly havent checked
Sprak Plug wires(?)-----brand new
MSD connections from box to coil (checked)
Vacuum leak (checked)
Compression (checked)
MSD Ground good (?)-----checked multiple times, even hooked a jumper cable from the post to the battery
Fuel Pressure settings(?)-----6-6.5 and steady
Type and Age of Springs(?)----new patriot duals
Check coils (fine)
Timing (Ok)
Spark plugs (?)---------have swapped them 4 times
Sprak plug gaps (?)-----as out of the box, honestly havent checked
Sprak Plug wires(?)-----brand new
MSD connections from box to coil (checked)
Vacuum leak (checked)
Compression (checked)
MSD Ground good (?)-----checked multiple times, even hooked a jumper cable from the post to the battery
Fuel Pressure settings(?)-----6-6.5 and steady
Type and Age of Springs(?)----new patriot duals
11-15-2011, 12:03 PM
#29
Staging Lane
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When its just idling, it doesnt pop, just when i give it any throttle. And ostly when i hit it fast, if I roll on the throttle its not as bad but its still got an odd stumble
11-15-2011, 01:30 PM
#31
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I've got a 94 mustang with a lq4, victor junior, holley 750, 234/238, patriot springs, and 1 7/8 dynatechs. Using the 6010 box. Ive tried the pills, and my own curve and the problem hasnt changed. It starts up just fine, but then stumbles and backfires through the carb and exhaust. I through a timing light lead over the plug wire to show when it was sparking, and a few of the cylinders seem to cut out completely when i hit the gas. I called msd and they dont know what it would be. I have changed cam and crank sensors, checked rockers, pushrods, timing gear alignment. Also made sure we had a good ground and constant 12v. Anybody have this problem or have any input, Im lost...
