Talk Morgan Forums Morgan Sports Cars Classic Morgans (pre-CX) 2006 4/4 Twitching Speedometer

New owner getting a bit desperate - in February we realised a 30 year dream and bought our first Morgan, a 2006 70th Anniversary 4/4 on 10k miles... seemingly great, but in the first weeks we noticed the car has an intermittently twitchy speedometer - see the video below.

https://youtu.be/TCDOTQs6-bk

01:29 onwards is the clearest example.

It's sporadic and will go for short periods without doing it, then suddenly have a good twitch. This does not seem to be linked to acceleration, gearchange or bumps in the road, it just seems to do it whenever and at whatever speed... Whether pulling away up to 30mph, or cruising at 50 or 60mph... or just steady state driving. Some are big twitches (10-15mph) and some small (2-5mph) Some individual and some grouped... very odd, I've never seen a vehicle do this!

As with all 2006 70th anniversary models it is a 1.8 duratec with ford box, so electronic speed sender on the gearbox output shaft, and no drive cable (so it's not lubrication or sticking drive cable!)

Car (under warranty) has now been with a dealer for a full two weeks, they have checked earths, power supply and wiring, now seem to be struggling to find the cause or a replacement sender to try.

Obviously this could be earths, supply, sender or instrument at fault.

Has anyone else had this issue, or know what causes it?

Hi,

Obviously, there's several things that could be the cause.

Has the dealer had the Speedo tested?
The suppliers, Caebont (Smith's instruments), are very helpful and will certainly test it.

Incidentally, my clock gave up living very early in its life but was rescusitated by them.

By the way, congrats choosing your car

Mine goes completely bananas above 80

Mine goes completely bananas above 80

@ Salmo
Cheers for the info - I had already spoken to CAI / Caebont last Tuesday 16/4/19; they gave me advice on earths, supplies etc and told me a few possible vehicle-based causes of the "twitches"; they also offered a test and rebuild in case the fault is in the speedo.

But no, the dealer hasn't tested the speedo yet despite now rolling into the third week of no car. Instead they are going to try out a new sender which we are waiting for and hasn't turned up - apparently this part is no longer available from Ford!

This spec of car was "the one" for us when we saw it - and we did truly love this car to start with (8 weeks ago) but this is one of three early faults which are rapidly changing that!

Ed, stick with it. 10k is a very low mileage for a 13 year old car. It will improve with use.

Hi Ed,

I just spoke with my nephew who has a small car repair business and he went straight for the sensor.

John is right....Stay with It.

Have sent you a pm.

My rev counter does it from time to time and to a lesser degree !

My 2005 has the gearbox output sensor, and has always pulsed at tickover, although on the road it's fine. The speedo is voltage sensitive, and when I had the battery fail, and jumped started it with a powerpack, the speedo was all over the place.

The later stub axle sensors don't seem to be anywhere near as sensitive.

The two speedos I've had on our 2004 Roadster have both twitched at tickover. I would suggest you live with it as others has said - it's a Morgan after all (actually that's no excuse but 39 years of ownership have done wonders for my stoicism).

Good luck with your ownership.

Roady