I live in Nor Cal where the roads are scenic, but awful. Over the past few months the XKR has developed a near constant little rattle seemingly centered under the center con. I assumed it was the glitzy trim piece (could do without that) around the shift knob, but its deeper in than that. About the same time the tach has had issues as well, showing both under and over the actual rev's. It seems to sort itself after a few starts. Not sure if they are connected (loose cable). Possible?

 

I have one of these in my console and dash bezel that I can't find to save my life. I did notice keeping change in the ashtray caused a rattle that sounded like it was under the shifter area. The rattle in the dash is going to the dealer as its driving me nuts.

 

The engine speed signal for the tachometer derives from the CKP (Crankshaft Position Sensor). This is processed by the ECM (Engine Control Module) and transmitted on the high speed CAN to the IP (Instrument Pack).

It's possible that a loose harness connector could be causing the intermittent reading. However, for anything involving the engine management system, I would always check for any stored or pending error codes as an indication of possible impending trouble.

Graham

 

Thanks. Given that I understood about 1/2 of what you said, I think its time I rattle on in and get it looked at. Remeber when it was a cable geared to the distributor.....

 

I miss those days too.

Don't we have the California EPA to thank for starting all this complex engine management and monitoring systems?

Graham

 

MaximA - Did you ever find the culprit? I have a 2009 XK rag top and I too have some strange rattle that seems buried deep in the dash.

 

I replaced my dash bezel with black piano and that did get rid of one of the dash rattles. Although there is another one buried deep in the dash that pops up every now and then, but got better after the dealer had to remove part of the dash to install a new evaporator. If some conditions are right it pops right back up then goes away. I have no idea what it could be, I can go track the car and doesn't make a sound. Drive to work three days later and it pops up.

The one in the console just comes and goes and drives me nuts. I think that one may be related to my exhaust as thats when it started.

 

Yes, same thing for my "deep in dash rattle". It comes and goes with a bumpy road or high frequency vibration caused by grooves in the pavement. It seems to be one the passenger side but even while my wife is riding it that seat, it's too hard to triangulate a position on. I haven't started taking things apart yet to look for it. I was hoping this was a known issue.

 

That sounds like mine and of course when I get to the dealer it gone. I have a few upcoming trips to the dealer so hopefully it happens when I'm there.

 

Fascinating. I notice on cold starts, the tach seems to bounce up and down by about 100 revs or so, but sorts itself out once the car starts to warm up.

I also have a rattling sound when going over rough pavement, but I assumed it had to do with the upper strut mounts.