Speedometer hand vibrates

the speedometer hand vibrates at high speeds and at times goes to zero, then returns. What can it be ?

 

The most common culprit is the speedometer sending unit that is located on the transmission and sends the signal to the speedometer. I would replace that first as it is easy to change but unfortunately not cheap.

 

There are early and later designs also of the sender, so look at what you have before blindly ordering the part.

 

Many thanks. Is the same for other car, like fiat, Alfa Romeo?

 

this problem arose after I changed the belts, can it be connected?

 

How do you get your car to go fast? While I absolutely love driving the 308 mine is not a fast car.
Joe

 

Is 150mph not fast enough for you?

When I first bought my gt4 I went 120mph on most motorways and it was quite responsive enough to overtake traffic on A roads. I thought 1.5T was quite heavy, but compared to modern cars it's actually pretty light. OK so it doesn't do 0-60 in 3.something seconds, but it's still plenty quick enough, and it's physical enough to actually need driving.

I don't really get all this 308s are not fast cars stuff.

 

Check the electrical connector for the sender at the frame inboard of the lower a arm

 

My Fiat 124 and Alfa Spider were both mechanical drive speedometers but the Ferrari is electrical. Maybe later Alfas were different?


Sent from my iPhone using FerrariChat

 

https://www.ferrariparts.co.uk/part/ferrari/116987
https://www.eurospares.co.uk/Parts/116987/Ferrari/New/55045
https://www.superformance.co.uk/328/electrical.html

All priced at @ £319.73 /$410 with tax (+ shipping) - No, not as cheap as they might be, but if it lasts another 30 years plus, then that's less than 3 pence/ 4 cents per day

No.76 on this diagram: https://www.ferrariparts.co.uk/Diagram/Ferrari/328-GTB-GTS-(1988)/027-Gearbox-Differential-Housing-And-Oil-Pump

The first thing I would check is the plug connector (loose/dirty?), followed by the fitment of the sensor into the gearbox housing (has it come loose?). Then I'd check the how clean the face of the sensor is (is there anything on the face that could cause a false trigger?), and then I'd look at replacing the sensor.