Need help, no spark
Thread Starter
|
Mountain Pass
Joined: Jul 2000
Posts: 189
Likes: 9
From: Minnesota
Need help, no spark
Hi guys. I need some help. I just bought a 85 F150 4x4 with a 351 HO in it. It also seems to have a black cloud hanging over it. I have had problem after problem with it so far in the month that I've owned it. Anyway this morning on the way to work it just up and died. Started up and died a few seconds later. I had this same problem about 3 weeks ago and found, by accident, that I had a bad wire or wires between the ignition module and the coil/distributor. I changed all five wires, the 3 that go to the distributor and the 2 that go to the coil. Thought I had it fixed until this morning. Any ideas? Any and all help will be appreciated. Its getting real frustrating.
Thanks
Thanks
Senior User
Joined: Dec 2003
Posts: 354
Likes: 1
From: Memphis, TN USA
You said that the you can start the engine and then it immediately dies a few seconds later right? If so, the ignition switch should be on the ON position (right before the crank position) and then use a multi-meter and measure the voltage on the ignition coil wire. Just tap in the positive of the ignition coil wire and tap in other on the engine block. In the ON position you should get around to 7 Volts and f not you have some problem probably in the ignition switch. When you crank the engine, you should get around 12 Volts. It is because when you turn the ignition switch to crank the engine, it by-passes the resistor and hence you get 12 volts. Once you release the key, it should be on the ON position and then it is now connected to another wire with a resistor on it and that why you get around 7 Volts.
BTW, what kind of ignition system is this Duraspark II, III? Is this carb or Fuel Injected?
BTW, what kind of ignition system is this Duraspark II, III? Is this carb or Fuel Injected?
Thread Starter
|
Mountain Pass
Joined: Jul 2000
Posts: 189
Likes: 9
From: Minnesota
This truck has the 4bbl on it. Weird thing is when I went to tow it home yesterday, got in it and it started right up. Drove for home. Just got into the town where I live, about a 15 mile drive and was going down the road and it just died. Same as what happened in the morning. Let it sit for about 10 minutes, it started and I made it about 2 1/2 blocks and just died again. My buddy and I decided to let it sit for about an hour, seems to run after it cools down, or so we thought, went back and it wouldn't start at all. So we towed it to a friend who is our mechanic and told him to work his magic. Any thoughts or ideas that you guys have to help him diagnose this and get me back on the road would be great. I'll call him today and tell him to check the voltage at the coil.
Thanks in advance for all the help given.
4fords
Thanks in advance for all the help given.
4fords
Senior User
Joined: Feb 2004
Posts: 105
Likes: 0
From: North Carolina
If you have the duraspark II system, the module from Ford is about $100, but I got one at autozone for $15. Comes with a lifetime warranty, so if it is a knock off piece of junk, buy two, keep a spare behind the seat, and keep swapping them out. But I was told that there was a problem with the Ford boxes that the aftermarket fixed. Haven't had any problems with mine so far..
Post Fiend
Joined: Jan 2000
Posts: 5,330
Likes: 17
From: Dryden, ON, Canada
Personally, I've never seen an aftermarket one that lasted anywhere near as long as the Ford ones(perhaps that's what the aftermarket fixed?) The one on my F250 is the factory one off of a 78 F100...
I grab all the old ones I can, test 'em, and keep the good ones.
I grab all the old ones I can, test 'em, and keep the good ones.
Trending Topics
Senior User
Joined: Jan 2004
Posts: 111
Likes: 0
From: Vancouver
I have had the same problem as you listed.Three times the magic bo
module box)once the coil,and twice the pick-up in the dist(those three wires that go into it).The magic box seemed to act up as soon as you load the motor up.Coil was when the motor warmed up.Dist pick-up was real eratic and one of those take it into the shop and it woulden't do it kind of things(needed to be warm and under load).
module box)once the coil,and twice the pick-up in the dist(those three wires that go into it).The magic box seemed to act up as soon as you load the motor up.Coil was when the motor warmed up.Dist pick-up was real eratic and one of those take it into the shop and it woulden't do it kind of things(needed to be warm and under load).
FTE Stories
Ford Trucks for Ford Truck Enthusiasts
AEV FXL Super Duty - the Super Duty Raptor Ford Doesn't Make
Brett Foote
Lobo Vs Lobo: Proof the F-150 Lobo Should Be Even Lower!
Michael S. Palmer
Ford's 2001 Explorer Sportsman Concept Looks For a New Home
Verdad Gallardo
10 Best Ford Truck Engines We Miss the Most!
Joe Kucinski
2026 Shelby F-150 Off-Road: Better Than a Raptor R?
Brett Foote
2027 Super Duty Carhartt Package First Look: 12 Things You NEED to Know!
Michael S. Palmer
10 Most Surprising 2026 Ford Truck Features!
Joe Kucinski
Top 10 Ford Trucks Coming to Mecum Indy 2026
Brett Foote
5 Best / 5 Worst Ford Truck Wheels of All Time
Joe Kucinski
Senior User
Joined: Sep 2002
Posts: 431
Likes: 0
From: Midwest
I would go for the ignition module. I keep one behind the seat on my 86, me and several friends have found it is easier swapping a-zone ones for free under warranty rather than drop the money for ford modules. From what I have found, after market ignition modules seem to be about as reliable as after market starter relays(I also keep an extra one of those in the truck.) But they cost less than ford and they have a warranty.