HAVE A DEAD MISS AT 1500 RPM WHILE DRIVING DOWN ...
1987 Jeep Wrangler
Have a dead miss at 1500 rpm while driving down the road. Have rebuilt carb, changed intake/exhaust gasket, and have a new icm?
Tuesday, September 25th, 2012 AT 2:23 PM
Scan for codes a and check for a vacuum leak. Then try to short out a cylinder one at a time to find out which one it is then check compression. If that's ok then check for bent pushrods/rocker arm problem etc.
Tuesday, September 25th, 2012 AT 2:26 PM
LAST TIME WE DID A FULL 100% TUNE UP?
GOT A REPAIR MANUAL?
WHAT'S NOT EXACTLY LIKE IT WAS...UNDER THE HOOD....LET'S SAY IN EARLY 1988?
I CAN LINK YOU TO OTHER POSTS, IF YOU ARE INTERESTED CONCERNING A "NUTTER BYPASS" AND BASICALLY MAKING UNDER THE HOOD, CLOSER TO A CJ.....SORTA ELIMINATING THAT PESKY SO CALLED COMPUTER
ARE YOU EMISSIONS TESTED IN YOUR REGION, THIS MAY NOT MATTER IF THEY "GRANDFATHER" OLDER STUFF ON THRU WITH JUST A SAFETY INSPECTION
PICS BELOW ARE OF AN EXAMPLE OF, "THAT LOOKS FINE"....but it really ain't!
CORRODED COIL CONNECTION ON CAP---IT LITERALLY HAD TO BE "BROKEN" OFF OF THE CAP......NOT TO MENTION HOW GOOD THIS CONNECTION STILL WAS (IT STILL RAN PERTTY DARN GOOD).....THE PICS WERE AN AFTERTHOUGHT, I SORTA STUCK IT BACK IN PLACE FOR THE 1ST ONE (YOU CAN SEE THE POWDER, THAT WAS NOT THERE WHEN I INITIALLY MAN-HANDLED IT)
THIS "LET IT GO ATTITUDE" IS EXACTLY WHY SCHEDULED MAINTENANCE IS IMPORTANT.......A "TO DO" LIST FOR DUMMIES!
I'm going to pull the ignition module and have it tested, it's new but it definitely acts as if it stops firing. I replaced the distributor, wires and plugs. If the ICM gets 3 passes i'm pulling the valve cover. Also if you get on passed the miss about 300 rpm it wil smooth back out!
Friday, September 28th, 2012 AT 11:05 AM
CORRECT OEM TYPE PLUGS?....NOT SOMETHING "HIGH SPEED" YOUR PALS SUGGESTED?....RIGHT GAP?
WIRES ARE THE CORRECT FIRING ORDER?
POSITIVE THE DIST DROPPED BACK IN CORRECTLY?
LOOKED FOR VACUUM LEAKS?
YOU HAVE SET THE TIMING CORRECTLY....WITH VACUUM ADVANCE VACUUM LINE TO THE DISTRIBUTOR PLUGGED OFF, WHILE YOU DID THE TIMING?
IDLE SPEED WAS BY THE BOOK WHILE YOU TIMED?
RECONNECTED WHEN FINISHED?
RESET IDLE SPEED AFTER TIMING WAS DONE?
YOU HAVE "TWEAKED" YOUR CARB IDLE MIX SCREWS....KEEPING IT AT IDLE SPEED AS YOU WENT?
THEY ARE 100% EVENLY BACKED OUT (LIGHTLY BOTTOMED--THEN BACKED OUT) WATCHING YOUR DWELL METER FOR IMPROVEMENTS AS YOU MOVED THEM, ONE AT A TIME IN SMALL INCREMENTS?
LETS HOLD OFF ON GOING IN, UNTIL WE EXPLORE SOME OF THIS
REMOVE YOUR AIR BREATHER AND GIVE ME SOME (4 OR 5) GLAMOUR SHOTS OF YOUR ENGINE --BOTH SIDES---IN FOCUS--(NOT TEENY TINY PHONE SHOTS) WHEREAS THE ENTIRE ENGINE TAKES UP MOST OF THE PIC (NOT CLOSE-UPS)
EXAMPLE OF A "SHOT" AT BOTTOM. THIS IS ONE OF MANY "I HELPED" THE OWNER WORK ON, AT MY HOUSE...I DON'T NORMALLY DO IT MYSELF, I MAKE THEM DO MOST OF THE WORK, THEY USE MY TOOLS AND I EXPLAIN THE "HOWS AND WHYS"...I DO DEMONSTRATE. MOST LEAVE "KNOWING SOME STUFF" AND HAVE THAT "BANTAM ROOSTER STRUT" WHEN THEY LEAVE. I DO WELL TOO, WHEN THEY ARE USUALLY GRACIOUS AND DONATE TO ME...I DON'T FIX THEM FOR A "SET PRICE". THEY DON'T FULLY FIGURE OUT MY "SCHEME OF THINKIN'" UNTIL THE END OF THE SESSION. I SORTA THINK I MAKE OUT BETTER THIS WAY. I ALSO HAVE CLEANER HANDS!
Friday, September 28th, 2012 AT 9:16 PM
Checked all the things from the last suggestions, and then preformed the nutter bypass. Fixed the problem completely. Thanks for sending me in the right direction!
Tuesday, October 9th, 2012 AT 7:43 PM
YOU OWE ME LUNCH!
GLAD YOU GOT IT FIXED
LOOK THRU THE CJ 5 AND CJ 7 FORUMS----THE ONES WITH MEGA RESPONSES ARE FILLED WITH INFO
MORE QUESTIONS. YOU CAN COME BACK TO THIS POST WHENEVER YOU WANT.