Can I revive this one? Did the OP ever get this resolved? If so, was it the cracked piece for the throttle cables he mentioned?

As I'm whittling down the list of stuff to sort out, this one is getting more on my hot list as I use it all the time in the other cars.

I did a real quick check of vacuum lines under the hood, and they all look good. One of the posts in this thread mentioned pulling the hose from the plenum and sucking on it (yeah I just said that... grrrrr...). That seems more definitive than a visual. Any more details on that process?

Just to be sure, I do get the orange light on the dash. In looking at the manual, the process to do the electrical tests look a bit over my head (or willingness to figure out), but any quick ones on that?

Based on research, it seems vacuum leaks seem to be the winner most of the time.

 

well I have to replace the vacuum actuator that the cruise control cable hooks up to. The plastic tabs on it are prone to breaking

 

So how did you determine it was bad?

 

Followed the actual cruise control cable from the throttle body. It's the outside spring on the throttle body(closest to the radiator) and see where it clips into the vacuum actuator. The vacuum pump works for that pretty much by itself. Those two plastic tabs broke on mine due to the heat in the engine compartment
The 3 circles here show where the linkage hooks up, where the vacuum line hooks to the rear of the actuator and where it hooks to the vacuum pump.

other than that it's only hooked up but one connection from the wiring harness.

 

There is the full component layout. Only other option I could think about would be the cruise control ecu coming unplugged since it's besides the accelerator

 

Yep, found and studied the full system layout and such in the manual, so I know the components- I'm just hoping for the simple fix.

So in looking at your last pic here I did a couple quick tests:

- pulled the hose leading to the plenum and tried to blow in there (basically tested at the bottom circle you made). No dice. I think this is good.

- Then I pulled the hose from the back of the plenum (basically the other end of the same hose) and sure enough, I could blow through it very easily. Methinks this is bad? As such, I think there is a leak there? It basically would be at the left circle.

Also that component is just kinda connected but not really solid. Could this be an issue as well. The plenum is solid, but the other part isn't. Methinks I need that if it is bad/has a leak.

 

well take the vacuum hose off totally and check it that way. I don't know if there is a check valve in that 3 way connector or not. If not you just might need a new vacuum hose. How long ago did it quick working

 

Definitely not the hose. Very pliable and perfect seal at each end.

And yeah, that's my question- if there is a check valve at the 3 way? Wanna run out and pull yours off and see if you can blow through it?

 

I would but it's under a cover a raining cats and dogs right now

 

No worries. I was being a smart alec.

In studying the diagrams in the manual some more, it seems that there must be a leak. Even if there was a check valve, pressure would not be able to be maintained in a manner that would keep it going.

I bet this is (hopefully) the issue.