I have a 2WD 1996 F150 with a 5 speed. It is the wife's truck so I don't drive it much. The symptoms seem to be a very short hesitation or almost misfire when the truck is put under load. This happens when you accelerate both mildly and hard but moreso under hard acceleration. She said that it stalls sometimes when she turns corners.

I have the Alex Peppar scan software and there aren't any codes and I can't seem to find anything that could cause this. My first thoughts were that it was probably misfiring but there is no evidence that this is true. There should have been evidence of this when I scanned it.

I changed the fuel filter thinking that maybe it was starving for fuel; but, there was no improvement there.

The truck has a quite recent extensive tune-up with replacement of most ignition parts including TFI module, coil, rotor, distributor cap, plug wires, and plugs.

Any ideas?

HL

 

Do you know if the timing was adjusted? My friend just had his brand x tuned up by a shop, and they adjusted the timming without disabiling the ECU and had the same problem you just described. I'm not sure what you would need to do on a 1996 ford to disable the computer controlled timing but I'm fairly sure it involves removing a cap on a spout connecter( ford lingo for electrical connecter) and bridging the two wires with a papper clip or stiff wire with the key off. After you do this start the vehicle check the timming with a timming light, it sould be +/- 3 deg from TDC. This will be your non-computer controlled base timming. Do not drive the vehicle in this mode it is called fuel service mode or limp home mode and you run a high risk of destroying the catilytic converter if you drive in this mode.

 

Sound's kind of similar to a problem I had on my 96 4.9L. It would sputter and want to die when accelerating, I kind of had to feather the gas pedal to keep it running. I first thought it was a vacum leak but all my line's looked fine, but I started looking closer and the black rubber ends of the lines had small hairline cracks, so I just replaced them all and it solved the problem.

How long ago did you change those plugs? Did you check the gap before they were installed?

 

The plugs along with all the other parts were replaced about 8000 kms ago. I gapped them all at the time of install. The truck was running great and averaging about 21 mpg. The hesitating and rough running just started recently. I thought about the vaccuum lines but they look pretty good. I guess I should have a closer look.

HL

 

Check previous posts on the egr restrictor topic, this may be of some help to you