fordguy17

ya'll are probably tired of these posts now but i have got to figure this out so bear with me please...

the symptons are a bad misfire throughout the entire rpm range, and it seems to get worse as the rpms rise. it pretty much makes the car undrivable with all the bucking and jerking. also, everytime it misfires the tach jumps.

so far i have replaced:
some vacuum lines
ignition coil
spark plug wires
cleaned the mass air sensor
cleaned salt/pepper shakers

cap and rotor only have a few thousand miles on them as well as the spark plugs and fuel filter.

i pulled all my plugs yesterday and three of them 3,4, and 7 were white indicating a too lean condition. the rest of the plugs all had at least some oil deposits, some more than others.

according to the hanes manual this can be caused to worn valve guides or piston rings causing a misfire. I'm hoping thats not my problem but why are three of my plugs white? clogged injectors?

also is it possible this miss could be caused by a bad ground? i have been told that so i'm curious as how to check for one.


thanks everyone!

turt

You need to check compression and fuel pressure. After that let me know the results.

dimebag

mani forgot how much i loved your car... **** im diggin those rodlites too

15austin

Could be the Pick Up Coil in the distributor, maybe a head gasket.

fordguy17

fuel pressure is set at about 41psi. i'll get back to you on compression.

fordguy17

the oil is looking good, so i don't think it's a head gasket.

where is the pick up coil? is it visible if i take the cap off? i did find some magnetic dust inside of it a few days ago, cleaned it out and drove a few miles but i don't see anymore dust now.

thanks for the compliment dimebag!
and thanks for the help to everyone else!

ahittz24

What are your mods? when/how did this start? For instance if you just did a manifold swap, did you cross up any of the injector plugs? Have you sprayed carb cleaner around the intake mani with engine running to find a vaccum leak? Any smoke coming from the exhaust? if so what color? Get back and let us know

mypony89

I know you said that you cleaned the MAF sensor but it may actually be bad and need to be replaced. I had the same symptoms and thats what I had to do. After that it ran good.

fordguy17

mods are: 3.90 gears, 3000rpm converter, shift kit, trans cooler, u/d pulleys, full exhaust w/o cats (headers, x-pipe, mufflers, dumps), msd coil, ported stock lower intake manifold, K&N filter (its clean).

it started while driving home from the gym one day (it was raining) and it missed bad and the tach jumped while cruising at about 60. it did it a few times coming the rest of the way home. it misses so bad that the entire car will buck.

i have some blue smoke coming from the exhaust upon start up after letting it idle for a while. it does use about 1 1/2 quarts of oil every 3000 miles, but i have never seen blue smoke unless i start it up for the first time of the day and let it idle for a few minutes. it will go away shortly after.

i will double check the injector wire but i havent touched them in a while. i will also spray carbcleaner around the intake manifold.

rez_rocket

Might help, my friends stang had a similer problem, was hesitating and felt like the timing was off, we pulled the gas tank and found that the gas line had a small tear in it and was leaking fuel back into the tank. the tear was near the fuel pump so we couldnt see it or smell the gas. replaced the pump and problem solved.