1996 E350 v8 7.5 was test driving and setting cruise, at first cruise engaged and worked, then when under load going up hills the cruise disenguaged itself. After this maybe 4 or 5 times the cruise quit enguaging or working altogether. Checked fuses and didnt find any blown so what are the possibilities? Thanks in advance for any advice?

 

OK, look at you right foot. Is it still there? Boom, cruise control. Press down to go faster, let off to go slower.

I tease. I could be wrong, but I think a the cruise control operates on the vacuum system. Check to see that your vacuum seals/etc. are functioning properly. It shouldn't be too difficult because most cruise control systems are easily accessible. However, I am unfamiliar with the '96 E-350. If you've got a good guy/gal at your local auto parts store, they should be able to diagnose it easily. If you don't, time to make some new friends.

In any event, you got this dude!

 

That ^^^ is NOT "funny" nor one bit helpful!

At any rate Remote95 you have the 460 gasoline engine correct? Post your symptoms and questions in the Electrical/Wiring sub-forum here---someone will have a schematic for your year and fuel type: Electrical Sub-Forums. If your VSC is similar to the '97's and later the circuit is fairly easy to troubleshoot. Believe it or not a bulb in the CHMSL (Center High Mounted Stop Light) making intermittent contact could also cause your issues.

I believe your Vehicle Speed Control (aka "cruise control") is electrical in nature as your symptoms mimic a loose connection or possibly failing part. This could be the clockspring or the servo itself having problems maintaining its settings. I'm not too familiar with your year chassis but there might be a secondary brake actuation switch mounted on the master cylinder as well--another known part to fail or act intermittently.

Hope this helps.

 

I have a 1990 E350 whose Cruise Control quit working. I fixed it myself.

My first issue was there is a braided steel cable that runs from the vacuum motor to the throttle linkage. It slides inside a plastic tube, like your bicycle brakes. Each end of the cable has a metal bead crimped onto it. This is how a mechanism grips the end of the cable to be actuated by the cable (or to push and pull the cable).

Inside the vacuum motor housing the metal bead had come off. The end of the cable had become quite frayed. So the vacuum motor could no longer push/pull the cable.

I found an appropriate replacement stainless steel braided cable, and crimp beads. I did not spring for the special crimping tool - I used my bench vice to squash the bead in place. It's much like attaching those old split shot weights to a fishing line.

Second problem was my cruise control amplifier assembly (the "brain" of the system) was dead. Actually, it was missing. I think my mechanic removed it when I had him trying to fix the CC for me. CC used to work when I bought the RV and my mechanic was the only one who worked on the system (and failed both times to fix it) so I'm certain they removed the module.

I identified the part number and found a New Old Stock replacement. In my vehicle, the CC Amplified Assembly is mounted to a bracket by your right knee beside the steering column under the dash. You don't have to pull the dash to get at it. Since my bracket is also missing, I just tucked the module behind the carpet by the firewall and called it good.

I'm not sure how your 1996 is, but this is how it is for a 1990.

Steve

 

I'd go outside and look but it's raining here. Attached are the relevant pages from the Vacuum/Electrical Troubleshooting Guide for 92-96 model years.
I know how important the CC can be since I drive with hand controls.

 

I disagree. I thought it was both funny and helpful. That was my intention at least. Sorry you took it the wrong way.

 

Of course you disagree---who owns up to making mistakes these days? But by all means show how or where your post was helpful? And no this isn't a matter of me "taking it the wrong way" at all.

Fantastic post JeffreyClay--exactly what Remote95 needs for troubleshooting his VSC. Reps sent!

EVTM's when available for any Ford vehicle are invaluable for us DIY's. I've been able to collect all years E-Series from '97 to 2013 when the full bodied versions ceased production. I'm slowly collecting the later years when the E-Series became cutaway cab/chassis only. FWIW I find mine on eBay.

Remote95 please let us know what fix works.