very strange speedo fault

[richd]

its on a ph2 172 02 plate

My speedo keeps dropping to zero, more often in motorway driving, but its also with another strange issue, when the speedo drops to zero, if i let of the gas the exhaust starts poping like mad, it does not do this when the speedo is working ok. when it pops up working again it feels like i have just let of the gas very slightly, its almost as if the engine map keep changing, very strange.

Forgot to mention that no lights are showing on the dash

 

[Laine_16v]

You need a new sensor!

 

[George@RTR_Parts]

Aye about £20 iirc when had to change mine

 

[richd]

what would be the reason it pops when the speedo isent working?

 

[Laine_16v]

what would be the reason it pops when the speedo isent working?

Yes the car will act under a different set of paremeters when it believes the car to be stationary when its actually not. Mine was the same when it kept playing yo-yo on the motorway.

 

[richd]

ahhh that explains alots, got a long trip to wales next week so didnt want it to conk out lol. cheers guys new sensor it is.