I've got an EL falcon which has turned out to be a lemon,
If it hasn't been 1 problem it's been another. It started when the coil died, we replaced it and the distributor and the harmonic balancer (the balancer was because we thought it could've screwed up the timing) it wouldn't have power from take off.

That's good now to an extent but it now has a much more annoying problem, it will run fine half the time feels like a good drive and has, well as much power as it should, which isn't an astonishing amount for a GLi. But every so often mainly when it's a bit warmer or after a while of driving it will run like crap and it sounds as if it's missing and carrying on and it surges, shudders and backfires, mostly when taking off but even when just cruising on the highway. I've been looking at maybe low compression but it tested ok and it's weird that it will only do it, well in the worst possible times such as entering traffic and needing that speed to not cause a major accident.

Has anyone had this kind of problem?

did you swap the original gears on the dissy to your new one?

did you set the base timing correctly?

does it blow black smoke? 02 sensor might be f**k and flooding it, (had that happen before)

replaced fuel filter? plenty of fuel flow at the injector rail?.. while your there, suck on the vacuum line on the fuel regulator, if you taste or smell fuel the diaphram in it is f**k.

thats a start and all I can give you with the description youve given..

cheers, Tait

The dizzy came from a fairlane that was working fine until the owners cooked it but it was motorcraft which was the same as was removed from my car, I've replaced the oxygen sensors a couple of times but it didn't make too much of a difference (stupidly they were all second hand but being that I was sick of spending money on it I thought they couldn't all be screwed - a rookie move, I know), it's recently had the fuel pump replaced and the filter replaced in the last service, I haven't used a fuel system pressure tester but I had recently replaced the injectors as one of mine was cracked and there was a fair bit of fuel leaking as one of the o-rings were perished, so I believe it's got enough fuel, we tested the diaphragm in the fuel regulator and that seemed fine, it's got recent plugs and leads too.

Aah I was thinking maybe it was starving under load or had crappy spark but it seems fine until it screws up, sorry for the vague descriptions!

And we had set the timing by the book many times too lol

if the gears have not been kept matching, theres a good chance itll be chewing your aux shaft inside the block, which would cause your timing to jump around whilst driving etc.. = new engine time..

id be pulling that dissy out asap and checking your aux shaft. and swap the gears so their matching whilst your there..

base timing.. you bridged the 2 terminals and waited 2 mins for the revs to drop then set it?

could evem be as simple as a spark plug lead breaking down under load, id get a second set or a new set the try those.. cant hirt

engine needs air, fuel, spark and compression to run,

youve replaced the fuel pump and filter so id say the culprit is in the ignition side of things.

Yeah I had bridged the 2 wires when timing it, but I will pull out the dizzy and see if I can peek in and see the condition of the aux shaft, we have another car at my place that had the shaft broken twice which is why we got it cheap, that's probably what's happening, I'll take a look and let ya know, cheers!

I would replace the tfi module on the side of the dizzy. You said you replaced the dizzy from a engine that got cooked then the tfi has got to much heat and now is breaking down this is your problem:-)