Started after my fiance and her brother took my Lincoln to their mothers house. Persistent miss on #7 cylinder. Ruled out ignition (swapped wires around, swapped plugs, same cylinder same problem). Misses every cycle at idle, but for some reason while driving at certain RPM's, problem will go away, and have an intermittent miss, getting worse when engine is slightly lugged. Exhaust smells bad (but of course it does, the cylinder is loading up on fuel) Anyone have any ideas? Unfortunately I left my compression tester at my mothers, with no way to get it at this moment since my main transportation is screwed up, but compression doesn't seem to be the problem. Unfortunately I really can't do anything major to the Lincoln (again, because it's my main transportation) so I don't know how I'm going to fix this if it turns out to be something major.
 |
-
try replacing the distributor cap mang
1986 lincoln towncar signature series. 5.0 HO with thumper performance ported e7 heads, 1.7 roller rockers, warm air intake, 65mm throttle body, 1/2" intake spacer, ported intakes, 3.73 rear with trac lock, 98-02 front brake conversion, 92-97 rear disc conversion, 1" rear swaybar, 1 3/16" front swaybar, 16" wheels and tires, loud ass stereo system, badass cb, best time to date 15.94 at 87 mph. lots of mods in the works 221.8 rwhp 278 rwt
2006 Lincoln Town Car Signature. Stock for now
1989 Ford F-250 4x4 much much more to come, sefi converted so far.
1986 Toyota pickup with LSC wheels and 225/60/16 tires.
2008 Hyundai Elantra future Revcon toad
1987 TriBurner and 1986 Alaska stokers keeping me warm. (and some pesky oil heat)
please be patient, rebuilding an empire!
-
Which wires did you swap around? Did you check the coil to distributor wire? Also, when was the last time you did a cap and rotor change? I had a bad coil to dizzy wire that was arching against the coil bracket. It was running rough at idle and intermittently in gear at low rpms. I was lucky because I could hear the arching from outside the vehicle. Hopefully it's just a cap and rotor change since that's fairly inexpensive. I hope all goes well.
Friggin Lincolnmania, beat me to it. I gotta type faster.
PackmanComment
-
I've also got lower than normal vacuum, down two or three inches from normal.Comment
-
With the vacuum I would say you have a sticking valve.1984 CV tudor 351W, 4bbl, 5-speed best time in the 1/8 8.39 at 80 with 1.80 60ft time.
2006 P71, 1988 Bronco II, 1986 Baby LTD(5.0 & T5 swap in progress), 1976 16' Hobie Cat, 12' AquaFinn
http://www.cardomain.com/ride/2651997 UPDATED 20100826
sigpicComment
-
Check the spark plug, see if it's oil fouled.Comment
-
Comment
-
cap/rotor then prolly.
Only two things are infinite, the universe and human stupidity, and I'm not sure about the former. -- Albert Einstein
rides: 93 Crown Vic LX (The Red Velvet Cake), 2000 Crown Vic base model (Sandy), 2003 Expedition (the vacation beast)
Originally posted by gadget73
... and it should all work like magic and unicorns and stuff.
Originally posted by dmccaig
Overhead, some poor bastards are flying in airplanes.Comment
-
could be a compression or valve issue. Is vacuum steady low, or does it have a regular tick that goes along with the misfire? Usually a valve issue will show up on the vacuum gauge.86 Lincoln Town Car (Galactica).
5.0 HO, CompCams XE258,Scorpion 1.72 roller rockers, 3.55 K code rear, tow package, BHPerformance ported E7 heads, Tmoss Explorer intake, 65mm throttle body, Hedman 1 5/8" headers, 2.5" dual exhaust, ASP underdrive pulley
91 Lincoln Mark VII LSC grandpa spec white and cranberry
1984 Lincoln Continental TurboDiesel - rolls coal
Originally posted by phayzer5
I drive a Lincoln. I can't be bothered to shift like the peasants and rabble rousersComment
-
Replaced cap and rotor, no difference.Comment
-
re-torque the intake maybe? Could be a bolt worked loose and you have a vacuum leak at the edge of the intake. Also if there are any vacuum fittings in the #7 runner, it would be worth checking them.86 Lincoln Town Car (Galactica).
5.0 HO, CompCams XE258,Scorpion 1.72 roller rockers, 3.55 K code rear, tow package, BHPerformance ported E7 heads, Tmoss Explorer intake, 65mm throttle body, Hedman 1 5/8" headers, 2.5" dual exhaust, ASP underdrive pulley
91 Lincoln Mark VII LSC grandpa spec white and cranberry
1984 Lincoln Continental TurboDiesel - rolls coal
Originally posted by phayzer5
I drive a Lincoln. I can't be bothered to shift like the peasants and rabble rousersComment
-
No vacuum fittings, re torqued the intake with no change. I dunno what to do here, I can't tear into the car at this point since it's my DD. I know it's firing on that cylinder all the time but missing anyway. The thing is it doesn't always misfire on that cylinder. Could it be a bad lifter?Comment
-
Did you try switching the injector around to a different cylinder? You said the plug was fine, meaning no carbon or excessive gas? Any buddies or autozones nearby you can borrow a compression tester from just to make sure? You could always disable fuel and or ignition (i'm not sure how on these vehicles someone can chime in) and try just cranking it, it should be a steady even crank, if it speeds up for a brief period during cranking you may have uneven or lower than normal compression on a cylinder.-Phil
sigpic
+1982 Ford LTD-S Police Car. Built 351w, Trickflow 11R 190 Heads, Holley Sniper EFI, RPM Intake+ Hyperspark dizzy, WR-AOD, Full exhaust headers to tails. 3.27 Trac-Lok Rear. Aluminum Police Driveshaft. Speedway Springs+Bilstein Shocks, Intermediate Brakes, HPP Steering Box.
+2003 Acura CL Type S 6-speedComment
-
It's carbed, mang.
Did you pull the v/c off yet?1983 Grand Marquis 2Dr Sedan "Mercules"
Tremec TKO conversion, hydraulic clutch, HURST equipped!
Comment
Comment