car will run good till it get under a load?

I have a 87 5.0 and im having some major issues. The car starts and idles good will drive down the road but pops outta the intake. Ive timed it and checked all fuel and computer, mass air, etc... any ideas?

Coil

Does it have a msd box?

Coil or TFI

yes it has a 6al

Do the tfi's go out or do they gradually go out?

i have had then just go out and have had them act funny before they go out.

Do the tfi's go out or do they gradually go out?


They tend to do strange things when bad.


It could also be your ignition box. I would try unhooking the box and running straight through the coil.

Well i guess ill have to try that. Its been a nightmare tring to figuere it out. Im thinking its that or my msd box. Ive heard horror stories on them also.

Ive heard it could be a cam too. Is that a possiblity?

My car would run good as long as it was at 1/4 throttle or less after a 1/4 throttle it acked like it wasnt getting any fuel, i couldnt figure out what the deal was. It did this for about a week then one morning i was driving it and it died. Repleced the tfi module and it drove fine....... i also had a couple just quit with out warning. I keep a spare in my glovebox but that one will not let the car go over 50mph or 3200 rpm. If you try if backfires and boggs down, And that one is brand new.

Ive heard it could be a cam too. Is that a possiblity?


Thats a bit on the exteme side. I wouldn't worry about that.

ONe thing to note if you end up going the TFI modle route. You can have them tested but I have seen some test out a good and still be bad, just FYI. If you do replace it, make sure to use electrical grease on it.

allright. i appreciate all the tips. I hate having a car i cant drive or figuere out. So if i replace they tfi and it does nothing? What are a listof things you guys would test after the tfi? thanks

I would unhook the box first because that dosen't cost anything. Then if it continues try a diffirent coil. Then if it continues, TFI module.