Howdy! I have an 87 Bronco with a 351W and am having ignition problems. I am the original owner and have had various problems over the years but this one has me stumped, mad and just about broke. It started off where it would run bad after being on the highway for about 10 minutes, then it would run really bad after i got off the hwy. It seems to be heat related. But now is has gotten alot worse. I'll run to the end of the block and it'll start running really bad, spitting and sputtering when the accellerating.

I have replaced: 1) EEC Module 2) plugs/wires/cap/rotor 3) Complete distributor assembly (after 199,520 miles, i figured it could'nt hurt) 4) I replaced the Mallory Promaster coil I was using with the big ACCELL coil.

After replacing 1-3, nothing changed, still ran the same. Then I forked over 60 bucks for the Accel coil and put it on. Then it ran bad altogether, poor idle, no acceleration. So I bought a cheap OE coil, and it ran the same as it did with the Accel. The accel coil came with a resistor that it said was only for point type ignition systems. I've tried with and without it. To try and pinpoint a wiring problem, I took the stock positive coil wire off and hot wired the coil straight to the battery. It would not start at all, like it was getting no fire.

In desperation, I put the mallory coil back on and I'm back to square one. It starts and Idles, but spits when accelerating after its warmed up. I've already replaced everything i can think of and can't find any problems. I have the timing set at 10 degrees Before TDC with the vaccum advance off and plugged. I'm using the far right edge of the timing indicator where the word (TIME) is printed.
ANY INSIGHT ON WHAT MIGHT BE WRONG IS GREATLY APPRECIATED.

 

Just an idea - when a coil goes out it often wipes out the eec module as well. So if your coil were bad, then you replaced the module without replacing the coil, it is possible it could have wiped out the new module.

 

Exetremely plugged cat would cause some of your problems also.

 

I've just spent another hour and a half jacking with it. I've switched the new and old EEC units out several times and nothing has changed, but it is possible that they are both bad. I'm actually getting the best results out of the original Mallory Promaster Coil. Good power, just has an intermittent miss when accelerating. When I put the Accel coil on, it will crank and drive down the street a maximum of 100 yards, then die and the engine will be flooded. I think the whole problem lies in the coil. I think that the new accel coil i bought is junk. Thanks for the input.

 

A bad coil won't flood the engine. Pull the vacuum line off the FPR and see if there's gasoline inside it.

 

And if there is then what?

 

Then it's bad and needs to be replaced.

 

The FPR is bad? FPR is Fuel Pump R..........? I'm sorry I don't know a whole lot about this so bear with me.

 

FPR is the fuel pressure regulator. It's at the top of the picture.