Speedo Problem... HELP!!

[AdrianK]

Noticed today when driving that the speedo randomly displays a speed between 0-80 mph and varies madly within that range, so i am unable to tell how fast i am going.... The milage also changes at a different rate depending on where the needle is so thats affected too.

The rev counter however is completly normal. Any ideas on what could cause this??

Also dont know if it is related but... today i swapped in my new head unit, and in doing so dropped the screws. In order to get them back i had to pull most of the centre console out, and still i only found one.

Is there ANYTHING in that area that a stray screw could cause this with, or anything there i could of knocked whilst i was at it?

It could be completely unrelated, but it seems suspicious!!

Any help greatly appreciated. Thanks

Adrian

 

[mikegsi]

does sound suspicious mate, though i cant see a stray screw causing any probs, more likely youve disturbed something when you pulled the dash to bits!!

take it it did this only since youve installed the h/u, and did it straight after installation??

 

[AdrianK]

Its never done it before, but i drove the car a few times and a number of miles afterwards, it suddenly started doing it half way through a 25 mile trip and hasnt stopped since.

Are any of the wires to do with the speed sensors near the stereo or gear stick area?

 

[Duncs]

sounds more like a snag with the kph/mph converter really, although a bit odd as it happened after playing with the electrics

 

[pudski]

Had the same problem with my import DC2.
The problem was the converter :wink:

 

[AdrianK]

Thanks guys i take it TGM can change the convertor? are they expensive units?

Also i noticed today that even idling at neutral the speedo can still read over 60mph at times and is adding miles, very wierd, it also seems that if your accelerating the speedo works pretty much only does the funny business when the pedal isnrt down, its very strange.

 

[AdrianK]

Also as a side note i have just noticed that on idle, when the speedo lifts up to say 40+ there is a blip in the cars revs at the same time, anything upto 2500 rpm say, could the speed convertor cause this too? i would not of thought it would have anything to do with the throttle?

 

[jay.dee]

Speed convertor
Ask any importer if still not sure.

 

[AdrianK]

UPDATE

I have been to TGM and have had a new kph/mph convertor fitted, but this made no difference whatsoever. We then removed the head unit, and from that time onwards the speedo has been back to normal once the car is moving.

HOWEVER

I now find that sometimes (not all times) when i put the key in and turn it at the click where everything tests the speedo goes straight to 30 mph and stays there, meaning that reverse cannot be selected and milage is being counted even before the car has been started. Moving the car forwards however makes the needle drop back to 0 and the speedo works flawlessly from then on.

Has anyone had anything like this happen before or got ANY ideas as to what it could be? This lingering issues are driving me mad and i am spending money replacing parts that are fine to start off with!!

The only idea i have is that maybe a dodgy earth somewhere could be causing something like this?

Many thanks for any help or comments

Adrian

 

[Chief]

Doesn't sound too good mate. :cry: BTW good to meet you the other day. 8)

 

[AdrianK]

Yeah was good to meet you aswell mate, as you can tell it wasnt altogether successful in getting it fixed.

We were both there till haklf 7 working on it when everyone else went home. It looks like its going to be a bit of a mission!

 

[Duncs]

i suppose it could actually be the speed sensor it self, have you had it out.
it may just need cleaning :?

 

[AdrianK]

Yeah TGM took that out, said it had a tad of play in it, but looked fine really so he put it back.

As i say now the stewreo is out the speedo itself works perfectly once your moving, no wobble and everythings spot on, it just has the knack of displaying a speed before you actually start moving and it does count milage, i dont know what it could b.

 

[AdrianK]

UPDATE 2

Been back to TGM today, after more diagnosis, we managed to rule out the VSS as a problem, and also ruled out an earthing problem.

Have now removed the convertor and am running in KPH and it has been perfect since then, no issues at all. TGM have a different convertor on order now, going back to try it tmrw hopefully when it arrives, and hopefully that will be the end of the problems!

 

[Chief]

UPDATE 2

Been back to TGM today, after more diagnosis, we managed to rule out the VSS as a problem, and also ruled out an earthing problem.

Have now removed the convertor and am running in KPH and it has been perfect since then, no issues at all. TGM have a different convertor on order now, going back to try it tmrw hopefully when it arrives, and hopefully that will be the end of the problems!

Excellent news mate hopefully the new converter will solve the problems. 8)

 

[Suped]

when Tom removed the converter, did you check the wiring??

Hope the new converter solves all your troubles.

 

[AdrianK]

yeah wiring has been checked fully, tom was on the phone to the guy that makes the convertors, he gave us a list of things to try and it crossed off most of the potential problems all negative, so hopefully no expensive parts (except convertor) to get it fixed.