Cruise Control "Whistle"

Well, after replacing the switch, logic module and now the actuator (and yes, I checked the fuse at the start), my CC is STILL not working again. :confounded:

I had really suspected the actuator, but after I pulled the old one to r/r it with the used one (in better shape) I could tell that it was still holding vacuum. However, with the replacement, as it was with the original actuator, whenever I squeeze the actuator in situ I hear a faint whistle sound in response that seems to be coming from somewhere else in the CC system. Is this sound normal, or is it a symptom of something else amiss in the system? :confused:

Geez, guys … is this one too tough for ya? Can someone please just squeeze their actuator and tell me if they hear the faint whistle sound too? :slightly_frowning_face:

I recall wheezing sounds when squeezing – and my cruise control worked fine. When all power is off, the vacuum port is closed and the vent port is open. So you’re squeezing air out through the vent port. It’s a tiny port with a valve right in front of it, so it’s probably not surprising that it whistles.


Although he didn’t say so in his post, I believe that AttyDallas has a facelift car which has an entirely different cruise control actuator than the one you and I are familiar with.

I wish that posters would spend an extra second or two and add their year and model of the Jaguar that they are asking about to their posts.

Someone with a facelift may be able to help.


Yeah, the facelift cruise control is different, connected to the bellcrank with a ball chain rather than to the pedal assembly with a cable. I’ll bet it works pretty much the same way, though. Probably even wheezes for the same reason.

My 2004 Honda Civic has a cruise control that works entirely differently. No vacuum involved, it is electric. Has an electric motor that applies throttle, and a solenoid that instantly disengages tension on the throttle when the cruise is disengaged. It’s really neat, and note that it would work just as well on turbocharged or supercharged engines as well as diesels, none of which can use a vacuum-operated unit.

Sidetrack: On PowerNation, they are in the midst of finishing up restomod of a 1971 or so Dodge Charger, and they have shoehorned a Hellcrate 707 hp engine in it with a 6-speed T56 transmission. The other day they were refurbishing the front grille, which includes doors that open and close over the headlights. Basically they replaced everything that shows since you can get new parts cheaper and easier than trying to clean up old rusty bits. The doors over the headlights were originally moved by vacuum actuators, but those got replaced with electric motors specially made to replace the vacuum actuators. They didn’t even mention why, but the why is obvious: The Hellcrate is supercharged. It’d be bad to be driving at night, stomp the gas, and have the doors close over the headlights.

My 2nd fav car (after Jags, of course) - the Alfa Romeo Montreal - also use a vacuum-operated motor system for the headlight “eyebrows”, that are so neat on this model. The vacuum is applied to open the “eyebrows” whenever the lights are switched on. The “eyebrows” have horizontal slots in them and only close half way down the headlights, though, I always assumed that it was designed that way as a safety backup in case the vacuum motor goes out or a leak develops in the system and you can’t get the eyebrows opened – you can then still drive with the light that makes it through via the slots and the lower 1/2 of the headlights. :thinking:

Dang, Paul #2, I thought with all my posts about Superblue everyone by now was aware she is a face-lift (at least the regular posters). :laughing:

Seriously though, I don’t see why the admins apparently can still not incorporate that info into our signature lines, like on the old JLers’ forum. :confounded: This is supposed to be a new site with all the latest bells and whistles that the old site did not or could not have, so what’s the problem? :confused:

AttyDallas ,

Well, Kirby missed that you were asking about a facelift cruise control actuator so I clarified that for him. If Kirby missed that then you can bet that lots of others did as well.
I don’t see what is so hard about making sure each post includes the year and model on the subject line or somewhere in the text. I personally have no problem with doing that and your attempt to put the responsibility to do that on the Admins just doesn’t make sense to me. What is so hard about putting the year, model, and engine/transmission of the car you are posting about in the post somewhere?


It just seems unnecessary (or should be) … So where on YOUR posts does it show your car(s)? As for Kirby … well never mind :zipper_mouth_face:

Maybe I should just head off to that “other” Jag forum - and probably should have done that as soon as the “new” JLers happened, like many other former members did … I would point out they DO have an info. signature line on there …

We did implement a way to identify which cars you have, it’s the “My Cars” field in your profile - if I’m not mistaken I implemented it in the first week after we went live with the new platform.

The platform itself doesn’t have a signature line feature - the developers are of the opinion that it bloats posts unnecessarily. I happen to agree: the information is available in “My Cars”, and users such as yourself, who have gone so far down the rabbit hole that they have more Jags than their kitchen has spoons, would still need to mention which specific model they are asking about regardless of if the list of cars was in each post, or on their user profile.

Good point, Andrew. I had forgotten about the “My Cars” listing. I have gone ahead and trimmed my list down to the (two) Jags I presently own. The remainder of the list cars are clearly marked “RIP”. Only one of my current Jags is an XJS, so it should now be a no-brainer. I’m curious as to how Kirby though got that tag line in his posts re: his authorship + the XJ-S he used to own (btw, Kirby, you presently don’t own any? :astonished:). Seems that’s how we should be able to fit our car(s) into our posts. :thinking:

Kirbert has put that information into his “Name” field.

The point remains the same: If you have multiple cars, then a list of them, RIP, WIP, or MAT, will not help others figure out just which one you are asking for help on.

You can fit your car into your post, just type which car you are referring to in the text.

Preferably in the very first post of the thread. Some of these threads march on for weeks if not years. When one wants to check which car is being discussed, sometimes it’s helpful to simply scroll right to the top and read the first line. Otherwise, have to scroll and scroll and scroll trying to pick up a hint.

And no, I don’t make it a habit of memorizing which MY cars you all have. Sometimes I’ll pick it up, certainly, but I agree with Andrew, a post should include what car is being discussed in this thread.

Hmmmmm … never heard of “WIP” or “MAT” :confused: And it is my understanding that whenever a member refers to a Jag of theirs as “RIP”, that = they no longer own it, generally b/c it went ka-plooey. :funeral_urn: But I understand where you guys are coming from …

WIP: “Work in Progress”,
MAT: “Machine about town”.

O.K. as to the former. But what in the heck is a “machine about town”? :confused:

The mechanical equivalence to “Man about town”, i.e. a “runner”.

O.K., I have revised my header line. What do you think of that? :+1: It’s not rocket surgery - we need to get the word out (admins?) to the members that they can do that with their header lines in lieu of a signature line so as to avoid confusion over the model(s) and MY(s) of their Jag(s).

Hmmmm … I see on this post (unlike on my test post in The Pub) it cut off the line at the end with Andrew’s name … ugh! Oh well, at least the XJS info is present!

I tweaked it a bit, and now everything can be seen in the header line. :triumph: I notice also the site has put that line in retroactively on all my previous posts, FWIW. :smile: