Much time spent in researching possibility and finding no relevant post. This time last year this "No Start" issue surfaced. It is cold here again. Again. I have this intermittent issue to deal with. Here is the finding when NS - pop hood , key on , high volt probe w/ no HV (jump solenoid to crank) , within a few minuets of poking around - whether I am wiggling wires or tapping suspect components I'll hear a sound similar to that initial ignition connection that is heard when the key is turned - prior to engaging the starter (~2 sec.) In other words , I know then, that it will start. (I reconnect , shut the hood and start her up).
This happens - when it does, first thing in AM , and less often later that day. Otherwise, it operates as expected. I can't find the problem if it's not broke!
I'm replacing the TFI control module today. This is the thing, she started yesterday after I was probing the module. I took it to ground replicating the pickup and that action gave way to that "sound" indicating an OK to start'er up. Where is that noise coming from? And is that the culprit?? NB The ck. engine light does come and go with little miles between indications- 2nd oxygen sensor is slow to respond...
PS I've had a number of people stop me and ask if I'd be willing to sell her. Nope she's a keeper! Additionally, I'm new here - I have a 1996 F150 supercab 8' bed 5.0 XLT 209K miles

 

You have several relays energize during key on ... EEC, fuel pump, etc. Perhaps that is what you're hearing. You mentioned jumping the solenoid, and I'm going to assume you were doing that for convenience of being under the hood, and not because there is an issue with your ignition switch. So I'm going to assume when you turn on the ignition switch, things are normal - dash lights, radio, etc., comes alive.

Im pretty sure you need a signal from the PCM to your PIP and TFI before your going to get any HV. The TFI module is certainly a suspect for no HV, but your mention of not hearing the relays has me thinking of those 2 little small ground wires with black disconnects that connect to the neg battery terminal. They are notorious for intermittants, and one of them just happens to supply the PCM ground. I think they are there on the 96 version, may only have one small one. If so, check corrosion where they connect at the battery terminal, and pop the disconnects apart and inspect the connections. If not that, it sure seems like an intermittant from your description. Do some wire wiggling and listen for the "click." Good luck.

 

i hope you haven't tossed a TFI module at it yet. it's not clear to me from your post whether you have a "no crank, no start" or a "cranking no start".

 

for convenience - The truck did start before I did anything yesterday - like there was no problem, so I replaced the TFI?? Will it start today? Maybe... I'll be checking the ground connection at the battery either way - thanks mm

 

"cranking no start"

 

Can you put this in english....?

Do you have spark when cranking ?

 

I read this as - he was probing the coil and had no spark, and was jumping the solenoid while under hood so he could watch the HV probe on the coil.

 

I'm back probing for the HV intermittancy. I am getting too familiar with this trucks operation. Not a bad thing tho... It always cranks. It ran great for three days and then it wouldn't- even tho it cranked. I followed the Haynes troubleshoot procedures. I watched and replicated the Scanner Dan procedure yesterday. Yesterday it did start. So I was testing what I should see as if there was no problem.
My grounds have no "connectors" at the battery - three wires ground to fender, 1 from the battery ground and 2 go within 6 inches into wire harness. Again, I can't find this issue if when probing (key on run) that noise appears and I'll know then my HV will be working. I could continue to swap out parts. The new ICM did not set this right. What next??

 

You read that right.