firedawg

I was driving my 91 the other day and as i was turning left it quit. all the power was on but the car would not run. i checked for a spark and it was very little, not while it was turning over but as soon as i stopped. i replaced the ignition modual, and the coil and it continues to do the same thing. do you think that it is the distributor or the starter modual in the steering colum? all the help would be great.

Jugador

power steering puts a load on the engine so if you're at low rpms and turn it may die

90GTRagtop

Did it cut off suddenly like cutting off the switch (No sputtering or anything)? Also, are you saying there is no spark when the engine is turning over, but that it sparks weakly when you turn the switch off? Is the distributer turning when the engine is turning? Have you pulled any codes from the computer? These answers will help to diagnose the issue if it is an ignition problem.

bobby

up, my granpas truck will do that sometimes, its got over 30k miles 93 f 150

roundman

does it run at all with the weak spark or is it dead? check to see if you're getting 12 volts to the coil with the key on but not in the start position. if not, then the ballast resistor is broken or bad. if yes, then the bypass circuit around the resistor which comes into play only on a start could be bad. which module did you replace, the one inside the distributor or the one on the outside?

firedawg

it sputtered twice when it shut off. yes there is no spark while it is trying to turn over. the distributor is rotating. i have not checked the codes. i replaced the ignition modual on the outside. it will not even start up. how do i check to see if i am getting 12 volts to the coil? if the ballast resistor is bad where is it located and do i just replace it? is it all dealing with the distributor? if so should i just replace the whole thing? thanks for all the help.

90GTRagtop

Check voltage by connecting the + lead of a DC volt meter to the + wire connecting to the coil and the common to the - terminal on the battery. Personally, I don't suspect the resistor, because it should be bypassed when the starter is turning. But to confirm that the starting circuit is OK, you should check the voltage when the engine is turning over using the ignition switch. I haven't had to go into my 5.0 HO, but I suspect that it has a TFI (Thin Film Ignition?) module inside/outside the distributer like the normal 5.0L engines. These units tend to go out suddenly. I went through one or two on a 90 F-150 with the 5.0L (not an HO). That module may very well be your culprit. It seems like the code I got when this module went out was related to a loss of signal pickup in the ignition system (it's been a 5 or 10 years ago). If you replace the TFI module in the distributer, it should come with some dielectric grease. It is important to use this on the plate indicated in the instructions that ususally accompany these parts.

Good Luck..................

roundman

according to my '88 factory shop manual, the ballast resistor is a special length of resistance wire located in the dash area coming off the ignition switch lead that goes to the coil in the run switch position and it makes special note about not replacing it with just any old piece of wire. sounds like something you need to get at the dealer if it's bad. there is a module inside the distributor that may have failed in addition to or instead of the TFI module on the outside. I would check for voltage to the coil and if it's OK, then you might want to get a new interior module for the inside of the distributor or get it towed to a good shop who can diagnose it properly and fix it rather than keep spending money throwing new parts at it when you don't really know which part is bad. they should be able to pull in the self diagnostic cable and it will tell them what is bad right away. sorry I can't be much more help than this, but the old days of throwing parts at it until you finally hit the one that's bad has long since gone since the parts aren't cheap like they used to be when it was just points and condensors!

firedawg

i really appreciate all the help. i wanted to change the distributor anyways to the MSD so i guess that it will be done sonner rather then later. i will consider taking to a shop but i don't know of any i can trust.

roundman

If all else fails, you could always go the the local Ford dealer shop but take plenty of cash with you! LOL