Very subtle cruise control glitchiness (1 Viewer)

[Mark W]

I recently noticed that when set at 65, or 70 (and likely anywhere else) my CC in my primary '80 has a very very tiny on and off nature. 99% of drivers would not notice it, but it is there. Instead of a rock steady throttle application on flat level terrain, it is a constant on and off. It is tiny, but it is there. I can, and do hold much smoother manually than the CC is doing. This HAS to affect fuel efficiency on long highway runs.

I have not compared it to any of my other '80s yet becaue i keep forgetting out it until I am driving the rig but I am pretty sure this is abnormal.

Anyone encountered this before?

Mark...

 

[ppc]

Check for proper cable tension between the actuator and the throttle.

 

[Kabanstva]

I recently noticed that when set at 65, or 70 (and likely anywhere else) my CC in my primary '80 has a very very tiny on and off nature. 99% of drivers would not notice it, but it is there. Instead of a rock steady throttle application on flat level terrain, it is a constant on and off. It is tiny, but it is there. I can, and do hold much smoother manually than the CC is doing. This HAS to affect fuel efficiency on long highway runs.

I have not compared it to any of my other '80s yet becaue i keep forgetting out it until I am driving the rig but I am pretty sure this is abnormal.

Anyone encountered this before?

Mark...

Mine is the same way. I bought it with the original throttle cable and it’s well past it’s prime….super sticky. I have a new cable that I’ll install and test but I know that’s the issue. My friend with a 97 4Runner had the same symptoms and a new cable fixed it.

 

[Mark W]

Mine is the same way. I bought it with the original throttle cable and it’s well past it’s prime….super sticky. I have a new cable that I’ll install and test but I know that’s the issue. My friend with a 97 4Runner had the same symptoms and a new cable fixed it.

Interesting. I had not considered that. I jumped straight to electronic considerations. My rig has 320K on it and has spend a LOT of time off road... lots of silt and mud and lots of water. I'll take a look at the cable. Easy to check and easy to replace if need be.

Mark...

 

[BILT4ME]

Interesting. I had not considered that. I jumped straight to electronic considerations. My rig has 320K on it and has spend a LOT of time off road... lots of silt and mud and lots of water. I'll take a look at the cable. Easy to check and easy to replace if need be.

Mark...

I was having issues where my CC would randomly cancel itself and I had to shut off the truck and restart to clear it and use it again.

I changed the throttle cable because it had lost all of its exterior sheathing and it was apparently sticking enough that the CC didn't like it and cancelled.

Once I changed it and properly adjusted the cables, all CC issues went away.

 

[CJF]

I changed the throttle cable because it had lost all of its exterior sheathing and it was apparently sticking enough that the CC didn't like it and cancelled.

Finally.

I remember years ago telling you that was causing your high idle, but as I recall, at the time you didn't wanna listen.

EDIT: My bad, you *did* fix it back in 2018.

 

[BILT4ME]

Finally.

I remember years ago telling you that was causing your high idle, but as I recall, at the time you didn't wanna listen.

EDIT: My bad, you *did* fix it back in 2018.

That was YOU?!?!?!

I was just thinking about that when I was typing that. I thought I had replied and said you were correct. That's hard for me to do......

That's when I realized the folks here have YEARS of experience with all different aspects of these trucks and everything has been done and tried at least once.

THANK YOU! Again.

 

[Rusty Marlin]

Cruise Control lightly surging at around 1Hz

Since re-gearing to 4.88's the Cruise Control is acting funny. The throttle is surging, but very lightly. Nothing shows on the Tachometer or the Speedometer, but there is a light acceleration and deceleration at around 1 pulse per second or second and a half. (1 to 1.5Hz) It's super subtle...

forum.ih8mud.com

I haven't figured mine out yet.
Some days are more noticable than others.
New throttle cable hu? Cheap enough expirement.

 

[Vision19]

Have this problem also, 55-62 Mph. I replace my throttle cable for different reasons, but a new throttle cable did not fix the CC for me. Partsouq shows the CC cable as discontinued for a 1994. Still trying to find a solution.

 

[jonheld]

I recently noticed that when set at 65, or 70 (and likely anywhere else) my CC in my primary '80 has a very very tiny on and off nature. 99% of drivers would not notice it, but it is there. Instead of a rock steady throttle application on flat level terrain, it is a constant on and off. It is tiny, but it is there. I can, and do hold much smoother manually than the CC is doing. This HAS to affect fuel efficiency on long highway runs.

I have not compared it to any of my other '80s yet becaue i keep forgetting out it until I am driving the rig but I am pretty sure this is abnormal.

Anyone encountered this before?

Mark...

I've noticed this several times on my LX450 as well as my old 91 FJ80. It is very slight, but it is there. I attribute this to 1980s electronics. I think the CC system is more of a throttle on/off than a linear application.
All cables run smooth with no binding on my truck and get lubed periodically along with everything else.

 

[77mustard40]

Ok I'm not crazy, I can feel a slight oscillation usually on a downhill. I haven't tried to investigate it yet but I like the cable idea, I need to replace my throttle cable anyway so I may order both.

 

[Mark W]

I've noticed this several times on my LX450 as well as my old 91 FJ80. It is very slight, but it is there. I attribute this to 1980s electronics. I think the CC system is more of a throttle on/off than a linear application.
All cables run smooth with no binding on my truck and get lubed periodically along with everything else.

To be honest this was one of my first thoughts when I first noticed it. I don't put in a lot of long distance, light traffic, constant speed, flat terrain driving on cruise control, and it is so subtle that it is possible that I have just missed it until now. I have not had a chance to look at the cable or adjustment yet. I think I will make it a point to take one of the other '80s out and obsess over the cc behavior in that rig as well for comparison.

Mark...