[1990]

This is strange as it doesnt happen all the time, ok, the car has the 3.0 vulcan, runs great, but sometimes when cruising along, the thing starts bucking and jerking really hard, acts pretty much like either the fuel supply is coming and going or the ignition is cutting out, i was on the way home from the store and it started the bucking and it quit, i threw it into neutral, fired it back up and kept going, turmed the corner and took off normally, started doing it really bad and quit, i threw it into neutral again and cranked and cranked and it would not restart, i coasted as far as i could and pulled over and cranked some more, nothing, finally i cranked it one more time and it fired right up, so i took off again and it did fine all the rest of the way home except for one time, i put it to the floor and it hit the passing gear and was winding up and it bucked a couple times, but didnt quit. Like i said, it doesnt always do it and i dont know how to diagnose this, i cant really afford to take it to a shop and since it doesnt do it all the time i dont think a shop would have much luck finding the problem, there are no codes or anything. Dont know what to start replacing first, thought maybe the pickup coil or the ignition module maybe, but i dont know if its fuel or ignition.? HELP!!

 

[1990]

,
I went back out and decided to drive it somemore to try to figure out what the problem is, i drove the thing for 45 minutes, allover the place, it only bucked one time and that was at wide open throttle, rest of the time it ran flawless, perfect, so i drive it home and when i got home i noticed the check engine light was on, so i got the codes and here is what they are..14 profile ignitionpickup circuit fault, code 18 SPOUTcircuit open, code41 oxygen sensor circuit indicates system lean right side.
thats what i got, dont know what any of it means, so what do you think going by these codes?
thanks

 

[1990]

anyone?

 

[Dan_in_WA]

Two of the three codes are related to the ignition system; ergo electrical problems.

First, I'd check out the ignition switch itself. When the car starts this behavior, does moving the key a little bit make any difference? I'd try moving the key towards the "Start" position when it does this, and if that doesn't make a change, move it back towards "Off".

That'd be my first step. Let us know how it goes.

Dan

Edit: If you are losing electrical power momentarily, I can see the O2 sensor reading lean - the fuel injectors quit for a few revolutions. The engine is sucking on a dry manifold. Just a thought.

 

[1990]

I replaced the distributor with a new reman today and still does it..

 

[Dan_in_WA]

I'm thinking of the ignition switch, on the steering column.

This particular part wasn't one of Ford's better ideas, apparently. <_<

When it bucks, is it acting like the key was turned off, and right back on?

 

[1990]

yes, but faster than a human could possibly do it, really quick..

 

[Dan_in_WA]

Sounds like a bad, or loose connection to me.

I could be totally off; I haven't seen the car. Ford has had trouble with their electrical connectors, too. It doesn't take much to impede a 12 volt signal.

I just finished fighting this battle on my Delayed Exit for the headlights. Sensor and timer switch both checked good on the bench. I finally got it to work right when I brightened up the brass contacts in the timer switch connector with a rubber pencil eraser. (I had to tear the switch apart)

You could try the same thing with the connectors on your coil and wiring harness, that's a cheap place to start. I use a tooth brush and some WD-40 to clean, then a light coat of petroleum jelly to keep things from re-corroding.