Engine has a bad miss and poor idle

Tiny
PLUMBFIRE
  • MEMBER
  • 1984 FORD F-150
  • V8
  • 2WD
  • AUTOMATIC
  • 190,000 MILES
I have a 1984 F150 5.8 with no power on 2 cyls #5&8 this is a 4bbl auto trans with new or less than 1 yr old carb, dist, control module, plugs, wires, cap & rotor, coil, elec fuel pump. I have 125-130 compression on all cyls and spark through all wires. However truck runs the same with or without 5 & 8 wires connected to dist. Please help. Thank You from Plumbfire
Wednesday, April 13th, 2011 AT 12:02 AM

3 Replies

Tiny
CJ MEDEVAC
  • MECHANIC
  • 11,004 POSTS
Usually something dumb! Even New stuff can be bad, and stuff being a year old could be bad too!

How long ago did this become an issue?

Been Timed?

Have you switched wires around (meaning swapping 5 and 8's, wires to other cylinders and seeing if they act the same on different cylinders?

Have you adjusted the carb mixtures. Have tuning tools? Or by ear?

This is all the time or just idle?

With dist. Cap off, is the rotor button shaft "Solid" or can you "Wobble" it at all, with your fingers?

If you squirt/ dribble a little fuel in the carb (passenger side barrel) with a mist bottle, ETC.--Does it change anything? Do this Outside, Fire fighting equipment handy!

Hope I can help you.

Your Turn

The Medic

If you have the ign. Module tested, do it 5-8 times in a row, if it fails the last few replace it---Test the new one the same way before you leave the store (Don't ask/ go there!)
Was this
answer
helpful?
Yes
No
Wednesday, April 13th, 2011 AT 12:57 AM
Tiny
DWB812
  • MECHANIC
  • 108 POSTS
:D You've returned one too many "new" modules also CJ?
Was this
answer
helpful?
Yes
No
Thursday, April 14th, 2011 AT 2:24 AM
Tiny
CJ MEDEVAC
  • MECHANIC
  • 11,004 POSTS
Dwb812 CHECK YOUR MESSAGES, SENT YOU ONE (CLICK ON YOUR NAME AFTER YOU LOG IN--LOOK LEFT)--THE MEDIC
Was this
answer
helpful?
Yes
No
Friday, April 15th, 2011 AT 3:34 AM

Please login or register to post a reply.

Related Engine Idle Rough Content

Rough Engine Idle
GUIDE
Rough Engine Idle
A rough engine idle condition is a common issue that many drivers face often indicating underlying problems within the engine, fuel or ignition system. We have created this...
VIEW MORE