[blacktalon96]

So far I have had a fuel system problem (fixed), ignition problem (fixed), chargeing problem (fixed) and now this new one as of a few days ago. when you get in the truck the check engin light will be on and there is bairly enough juice to light the dome light. But the barrery tests full. So when you turn the key NOTHING. Fuel pumps come on and that but No juice to turn on the lights, horn, hazards, radio, nothing. When you unhook the positive cable and touch it to the terminal you can hear the TFI mogual in the distributor click as well as a relay (believe its the ignition relay) and the check engin light comes on in the truck (this is with no keys in the truck mind you). I unpluged the ignition (under the dash) and it still does it. Olny time it wont is when you unplg the three wires comeing off the negative battery cable. My truck is a 1988 F150 4x4 with a 351 and 5 speed manual. No AC or power stuff in the cab. Just a bare work truck. If a new wireing harness dont do it Off comes the EFI and into the scrap pile those parts go. Im going 4 barrel intake with a Carb. make it easy no more computer

 

[bigblockbuggy]

Who tested your battery and told you it was "full". A volt meter doesn't cut it here. A battery has to be tested under load, by someone with a tester designed for this purpose.

If, after you get it professionally checked (most auto parts stores will check it free), and it still comes back good, then start checking all of your power and ground cables from the battery. Any corrosion, or terminals in poor condition, replace them. My bet is that it is the battery, but barring that, I would guess you have some bad cables.

 

[blacktalon96]

battery was tested at parts store and was good, I even put in my brand new Optima and the same thing. im getting power just not where it needs to be when it needs to get there. Im pulling the wireing harness tomarrow and checking everything

 

[sackman9975]

I do believe your problem lies within your battery post and cables. This happen to me and I cleaned the post and cables and no more problem.:beer

 

[Jeepcrusher]

I had the same thing in my T-bird and it was the neg wire to the engine, replaced it and started tight up.

 

[blacktalon96]

hey thanks guys ill give it a try. I really need a new wireing harness though. The previous owner worked for the shop I got ti from. It had been a shop truck from 88 (new) to 04 when I bought it. and the wireing has been hacked as you can imagin. so I have been slowly pieceing it back together. The check engin and engin light are always on (sensors not reading) and the oil PSI gauge doesnt work (but its getting good PSI that I checked) you know The truck mechanicly is perfect never had a problem but the electrical is a dam nightmere. thanks for the help guys. If it doesnt get going im half temped to pull the engin bay harness and go through it all piece by piece and see whats up.