Engine/Transmission (1994 - 1998) 97 cruise control is too responsive

[C Schomer]

My cruise control won't allow ANY loss of speed from the setpoint. Control is smooth and it overshoots a little but the big problem is that it blasts the throttle way too much on even the small hills. It tries to hold the speed exactly on the setpoint. I did a search but didn't find the answer for this kind of problem. I don't have vacuum problems with anything and the servo and entire area, including the battery is very clean and free of any corrosion. I think it was fine up to the 3k gov kit and now throttle response is too much for the cruise. I'm thinking the problem is in some programming or whatever controls the servo/vacuum. Any ideas? TIA! Craig

 

[illflem]

I gained 1-2 mpgs by desensitizing my cruise, throttle isn't all over the place now but the mph varies by 4-5. Fine by me. Just cut the vacuum line to the servo and restrict it. I used a 1/4" plastic barbed tubing coupler filled it epoxy then before it set up poked a oily needle though it, needle pulled out easily after the epoxy set. You could also use round stock and drill a hole but the hole should be less than 1/64", most drill chucks won't take smaller. Another option is a solid round piece of plastic, make a hole with a hot needle.

 

[Deezul1]

Did this start after the 3K kit? Springs may be set a little tight.

 

[Todd G]

I noticed mine surges a lot after I installed the 370's. Time for the fix no doubt.

 

[grtescpa]

Originally posted by C Schomer

My cruise control won't allow ANY loss of speed from the setpoint. Control is smooth and it overshoots a little but the big problem is that it blasts the throttle way too much on even the small hills. It tries to hold the speed exactly on the setpoint. I did a search but didn't find the answer for this kind of problem. I don't have vacuum problems with anything and the servo and entire area, including the battery is very clean and free of any corrosion. I think it was fine up to the 3k gov kit and now throttle response is too much for the cruise. I'm thinking the problem is in some programming or whatever controls the servo/vacuum. Any ideas? TIA! Craig

Mine tends to overshoot more with the amount of weight I haul. Cruise contol was never as good as the one Ford makes. Thats the only good thing I'll say about Fords.

 

[Blakers]

Mine holds right on the set point. Works beautifully and I like it that way. Not sure why you would think that's a problem.



I've driven gas engine jobbers and they lag terribly - just no torque to maintain the speed.



Blake

 

[danandamy]

Originally posted by Todd G

I noticed mine surges a lot after I installed the 370's. Time for the fix no doubt.

I've noticed the same thing after puting in the 370's. Dang cruise bounces the boost needle all over the place on every little hill. So "the fix" is I need to restrict the vacume a little?



surging dan

 

[C Schomer]

The gov adj. nuts are where they were stock. The cruise doesn't surge, it give it throttle too hard on hills. Bill, I'd rather see it drop a few mph going up and not try to get back to the setpoint til I'm at the top of the hill. Is that how yours does with the restrictor. I have some restrictors in my pnuematic control fitting box. They're really small but it's a place to start. I'm going to put it up at the cowling, where the cruise vac. line starts from - it's easy to get to. Thanks for the ideas! Craig

 

[illflem]

Craig, restricting it doesn't keep it from reaching the set speed it just takes longer. With it restricted you will have to use your foot for awhile when setting and resuming. The length of time will depend on the size of the hole. I realized better fuel economy using my foot rather than cruise long ago, the stock setup is just too sensitive. Even on flat ground in cruise a gust of wind would move my pedal an inch then right back, restricted it tries to do it but it but the response is slowed enough that before it fully reacts to accelerate it's already getting a signal to decelerate. Diesels love to be set at one throttle position and left there, no constant ups and downs. The governor will take care of load/incline fueling demands. You may have to tighten up your springs as others have suggested.



I originally restricted mine while experimenting with turning the cruise servo into a constant throttle device, a momentary contact push button for rpm up, another for down. Problem was I couldn't push the button fast enough to have precise control of the rpm setting, it would always overshoot till I restricted the vacuum line. It was electron fast. In doing this I found that the stock cruise did exactly what I wanted with only a 10¢ modification.

 

[C Schomer]

Bill, I was afraid it would just take longer but I'll try it. I won't be towing again for a few weeks to see how it does. Craig