I replaced the vac line from the pump along with all of the others. Wasn't too tough, just need to pull the jack, etc. The cruise control has worked with the same intermittent behavior described earlier since then.

My understanding is that the vacuum pump is a centrifugal compressor (vs. displacement type), and I will not be able to hold vacuum on it while it is at rest. In any case, it doesn't hold vacuum at rest.

I am aware of the 35MPH speed issue. Have problems irrespective of the speed.

I would consider myself pretty mechanically inclined: Just finished replacing rotors, brakes, repacking hubs and doing the CV joints last weekend. Will be replacing the oil cooler lines, transmission cooler lines, power steering lines, and cooling hoses next weekend. I have a new sump seal I will probably do at the same time as the oil cooler lines. Will be waiting on the head gaskets, as my seepage is "controlled" (and they are a pain to do). Somewhere along the line, I will be adding an ARB bumper/winch, but understand I have to modify the frame and bumper mount offsets to get it to fit on a '95. I think you get the picture.

I own several ohm meters and know how to use them. If you have the pin outs, and specs (voltage, resistance, etc.), it would be a huge help. I am thinking to test the ECU, VSS, Neutral Interlock, and the line to the vacuum pump. My guess is it is probably the VSS or the ECU.

Thanks for the continued advice.

 

The pump will not hold vac. No test for the ECU or VSS.
After reviewing this thread I'm going with A bad ECU. It will not re-engage sometimes after cutting out. A bad VSS would likely do so or show speedo fluctuations.

 

Just a follow-up to the group. The ECU was intermittently bad, and the coumn set/resume was intermittently bad. Thanks to "onlyfour" I was able to replace the ECU and column switch. Everything was working well, until the column switch broke (again)[8D]. I am thinking duct tape and a series of different size bricks for the accelerator will be my new version of cruise control.

This weekend I get to replace the transmission cooling lines and filter. That should be nice and messy.

 

LOL sorry I have the same problem. But I don't see it for months and then there it is! But mine is a lose wire I believe, since when the cruise decides it's done working for awhile my tack and speed goes down to zero even know I am still moving. When this does happen it's only for about 2-3 min. I just live with the problem.

 

Hey--You might actually have an easy fix. If your speedo and tach go to zero periodically and the cruise cuts out, it is probably the vehicle speed sensor. This sensor is located under the vehicle on the transfer box. Check to see that the plug is seated properly. If it is, you probably have either a wiring problem to the sensor or a bad sensor. The sensor is relatively easy to fix. Only a single hex bolt holds it in place. Its worth a look...

 

Forgot to add.. the part is about $100 at the dealer and you can probably get a used one for $10-20.

 

Thx for the info.

 

Sounds like a dry solder joint in the ecu i come accross it alot at work erratic electrical cutout but always works fine from start up temp fluctuations on ecu pcb sufface cause cracks in soldered joints sometimes hard faults to trace when dealing with mechanics interfaced as well...if u can open the ecu without damage! get a strong light and check every soldered joint on pcb....glynn

 

Thanks-I still have the old ecu and will have to crack it open and look.