I have a '96 Grand Voyager with the 3.0 liter motor, over 200K miles. I expect things to start breaking, but this is a bit baffling.

This past week, the radiator (factory) sprung a pinhole leak on the drivers side tank. No problem, Autozone had one in stock. Put it in Saturday & cruise didn't want to work. Looked around & found some wires that got close to the exhaust crossover tube but only one wire had insulation burnt off. Pulled those wires back & zip tied them out of the way. Cruise started working..................sort of.

When I set the cruise, I have to hold my foot on the throttle, then hit the resume before it grabs at the set speed. Then in a few miles it's over the set point I wanted. My thinking was I had a vacuum leak. I looked at it today & found a cracked plastic vacuum line. Replaced that & it still does it.

My question is: do I still have a vacuum leak? The engine doesn't run rough, the cruise just acts like it doesn't have enough vacuum. When it's set, I can click the resume & it will accelerate slowly 2mph, not like it used to. And I have to "help" it by pushing on the accelerator pedal. Or do I have a loss of voltage from the burned wire?

I'm kind of at a loss.

 

To set the speed control you need to be above 25 mph. If you had a vacuum leak, The speed control wouldn't set. Have you check the vehicle for codes?

 

No codes, all attempts were at 55-65mph. Had it working 'kind of' a couple hours ago, on the return trip home, it didn't work. I bought new plastic vacuum line & ends. Not sure what else it could be.

Puzzling to me. I have to work tomorrow, but will double check all the connectors Sunday. If they are ok, only thing left is the servo itself. At least that's my thinking.

 

Drove the van this morning, again doesn't work properly. Took 2 miles before I could get it to catch (60mph). Light on the steering wheel is present, no codes. I'm going to double check the vacuum connections this evening after I get home.

The main vacuum line has large connectors from the intake manifold to the cruise control box (under the battery tray). There is a small connector coming out of the cruise control box to a short vacuum tube with a large connector attaching to the servo. I think I have it connected correctly, but will double check that also.

 

Is the air bag light on? Because the problem could be with the clockspring.

 

No, clockspring was replaced by dealer on a TSB 2 years ago. I figured it out though.

Vacuum connections. I had mixed up the 90* connectors with a straight connector on the control box under the battery. The plastic tube that slips into the connector was slightly loose & the connector on the control box was slightly loose also. I was able to test this with my handheld vacuum pump & it leaked down after 15 minutes.

Replaced the questionable connectors with new ones & put the straight connector back to the intake & it works. It holds speed, grabs the accelerator pedal when setting the speed, resumes to set speed & increases speed with the resume button. All in all, it works as it used to.

Thanks Master Tech, you were helpful. I'm sure I will have other questions, but will start a new thread for those.