Engine/Transmission (1994 - 1998) Cruise Control is defunct

[gchas]

My cruise control his bit the dust. The first symptom was just a slow, but steady drop in the speed while it was engaged. Then, after a few stabs at trying to re-set it, it seemed to engage and disengage (as though it was trying to hold a speed, but couldn't). Then it flat quit working. All of this was within a timeframe of less than two minutes. I'd appreciate any advice from anyone out there who has expertise in the cruise control workings as to what I might do to remedy this problem. I hate to think of taking it to the local dealer All opinions are welcome. Thanks in advance.

 

[illflem]

Most times the fix is extremely easy, a broken vacuum line at the cruise servo under the drivers side battery. It usually breaks right at the servo, just cut at the break and hook it back up, there is enough slack. If that's not it check the rest of your vacuum system for leaks. It can also be caused by the brake light switch under the dash being adjusted too sensitive, but doesn't seem like the case with your symptoms.

 

[gchas]

illflem, Many thanks for your prompt reply. I'll check it out and post the results. What a fantastic site and awesome group this is!

 

[gchas]

illflem, I have done a pretty thorough inspection of the vacuum hose leading to the servo, but no obvious leaks have been found. Due to the inaccessible area in which the servo is located, I can't really see what's going on under the battery tray, even with a mirror. I plan to remove the battery tray and servo tomorrow (when it's cooler... . near 100 degrees here today) to give it a closer look. Let me know if you have any more thoughts. Thanks again.

 

[illflem]

Clean up the servo electrical connections while you're under there. The reason failures happen in that location is due to battery acid corrosion.

 

[gchas]

Yes indeed. There is clearly evidence of battery corrosion around the servo. It appears to have dripped down through the battery case. Hope that cleaning up the corrosion will solve the problem. Thanks again for the important tip.

 

[RChase]

Check ALL of the vacumeline I didn't think mine was bad but it did have a small hole in it which I could not find until I pulled it out all the way. Try to put some vacum on the line hookup next to the dash and see if it will accept vacume mine did't so I pulled the whole thing out to find the break.

 

[gchas]

Thanks, topcret. I finally got the battery tray out this morning, then disconnected the servo. There was lots of corrosion below the battery tray, and some on top of the servo. I think I have found the problem, but would like some confirmation from anyone with more experience. There is a small eliptical hole in the top of the servo casing (which I think is aluminum). It is somewhat irregular in shape, so I doubt if it intended to be there. Battery acid is no friend of aluminum, and it looks like it has been either eaten out by acid, rubbed out due to vibration friction with the battery case (doubtful) or a combination. However, if there was a round hole by design and it has just been enlarged by the corrosion, this may not be all of the problem. May I please have some input from illflem, topcret or anyone else who can help. Thanks in advance.

 

[gchas]

Clarification! Only half of the servo casing is aluminum. The back side is composed of what appears to be hard black plastic/rubber. This is where the hole is. It is not in the aluminum although there is some evidence of etching in the aluminum. I'm fairly sure that the hole is not supposed to be there, but would like some reassurance. Thanks.

 

[gchas]

Servo Replaced

I removed the servo, took it to the local dealer who verified it was definitely defective. The hole was apparently eaten away by the battery acid. Replaced it for $32. Have to install it now. That should be loads of fun. Thanks for all of the help.

 

[gchas]

Happy to report that the servo is installed and everything works great! What a job it was to reconnect the throttle linkage. Finally figured out that you need to prop the throttle open with something in order to access enough of the linkage to put the hairpin clip in. What a dumbo!! Thanks again for all the tips. Even though it wasn't a vacuum leak, the tips led me to the solution. What a fantastically valuable site. Without the help of folks here who are anxious to help, I would have been megabucks out of pocket to have someone fix this problem. Thanks again.

 

[illflem]

Hope it works for you , it should. There's a vent hole in the servo, sounds like the acid found it's way in there and did it's damage. Surprised the servo is so cheap, yours is the first I've heard of failing. Now if you don't want this happening again when it comes time to replace your batteries get Optima or another gel cell type. No leakage or terminal corrosion make the extra price well worth it. It can get worse, the acid can take out the paint on your fender.

 

[gchas]

Thanks, illflem, for the tip on the better choice for a battery next time. Ironic you should mention the paint. Actually, a considerable amount of paint had been removed due to the corrosion below the battery tray. While I had everything out, I sanded it all down, primed it and repainted it. All's well that ends well. By the way, the dealer quoted my $51 over the phone for the servo, but I have a mechanic friend who lets me use his account for parts purchase, so I saved a few bucks there, which proves once again that it's not what you know, but rather who you know that is important. I'm glad I know about the TDR discussion forum. Thanks again for all your help.

 

[Dennis Garrett]

At 160k, the cruise on mine started jerking a little when I engaged it. I looked it over, & found the cable to be frayed at the throttle end & worn through about 50%. I replaced that, & it's working like new.

 

[gchas]

Must have been a real fun project to replace that cable. It was challenge enough for me just to reconnect the existing cable to the new servo. But 160K isn't all that bad.