Hi,
It has been little while but I am close to getting it running. I have spark now and fuel pressure just need to get the injectors firing. They may be stuck, I need to check power to them first. What else controls the injector firing?

Brian

 

What did you do to get it spark back? Injector firing is controlled by the PCM, you should see a constant voltage at the injectors when probing with a DMM and the computer momentarily grounds a bank of 3 injectors in this case to fire them. This is where you could have a problem, if the engine portion of that I6 harness isn't pinned the same way as the original chassis portion then some signals would have no connection or are going to the wrong place.

 

Hi,
I am hoping that the harness are the same seeing they are only a couple years apart and both EECIV. Can anyone help me to see if there is a difference between the 1995 4.9l harness and the 1997 5.8l pin out?

Brian

 

I traced the no spark to a bad distributor, got that fixed, I am so close to getting this truck running. Hopefully someone can confirm the pin out, it could also be a couple of other things or bad connections or even stuck injectors. I am going to try some starting fluid see if that gets it to fire, then I know all I need is to get the injectors firing and I am good to go basically. Thanks for the help you guys really make a difference to help focus on the correct areas to diagnose a problem. Paul forgive my ignorance but what is a DMM?

Brian

 

DMM = Digital Multi Meter.

 

Brian, in case you were interested, I am doing the opposite of your swap...I am dropping in a 351 out of a '95 F250 2wd auto into my '94 F150 2wd with a 300 six and 5 speed. So far I have the engine, engine room harness, flywheel, clutch kit, and ECM. I won't be needing my 300 six ECM so I'll be happy to sell it to you if you think you'll need it.

Frank

 

Update,
I figured out that the underhood harness for the 5.8l is different from the 4.9l. The main connector beside the fuse box does not have the 12v switched power pin for the fuel injectors so I got one in a junk yard to swap that should get me running.

 

It is alive! I put in a 95' underhood harness and it fired right up. There is one connector on the right inner fender coming from the tranny that is different. I believe it is the O2 sensor, the bigger one is square and I think that is the tranny connector the smaller one next to it has 6 pins of which only 4 are used and the 95' harness had three pins and is shaped differently again I believe it is for the O2 sensor one being three wire style the original 97' four wires is this correct?

 

Just want to say unless you're doing 90% unloaded, highway driving, the 4.9 will not get better fuel economy. If you're towing at all, forget it. Same as the 5.4 gets better millage than a 4.6 in the same truck, because you need torque to get moving. You need to work the smaller engine harder, reducing efficiency. It's well documented where people swapped out bigger engines for a smaller one, and saw reduced mileage.