Yesterday I bought a 2004 buick lasabre. Its only got 44, 000 miles on it and it was very well taken care of but as soon as I got on the road and opened it up to about 65 or so the speedometer jumped up to 95. Now even in park the speedometer will sit at 20. Does any one know what could be causing this and if so how to fix it or how much it will be to get it fix. Please help. Thank you in advance for your time

im not sure how you would do it without a scanner but i would look at what the pcm sees and if it was fine there is something wrong with the cluster. sounds like thats the case if it rests at 20. is that with the key off as well?

[QUOTE=jwfirebird;1591795]im not sure how you would do it without a scanner but i would look at what the pcm sees and if it was fine there is something wrong with the cluster. sounds like thats the case if it rests at 20. is that with the key off as well?[/QUOTE

Yes currently its sitting past 140 (which is where it tops out) and thats with the key in the off position. Earlier today it was acting fine but then it stated messing up again.

I've been searching via Google, and I'm seeing numerous instances of failing clusters on many 2003, 2004 Buicks etc. Even seen some places mention a TSB, but cannot locate the TSB number.

if when it messes up the trans shifts fine, there is very little it could be besides something in the cluster

Ok so if the cluster is left as is it wont mess with any thing else in the car?

no basically if something is wrong with the cluster it wont affect the rest of the car. its alot like a computer monitor on 2000+ vehicles, it has a serial connection to the pcm and it displays what the pcm says to

Ok now my temp gauge is reading just alittle higher then im use to seeing (past the 1/2 way mark) would this have to do with the cluster or would it be the wiring? Whats the easist way I check this and see what it is. Also whats the eaiest way to check it if It can be done at home. If not do you have any idea how much this repair will coast me?

Usually its a failure in the cluster itself. Best way to tell, find someone that has a computer that can read live data and "see" what the PCM is seeing/doing vs what the cluster is doing.

Depending on the complexity of the cluster, it can range from $100 to almost a $1000 to replace a cluster.

Katelyn, Re temperature, If you car is equipped with the digital information display you can scroll though by pushing mode button to see what the temp sensor is reporting and cross reference it to the analog temp gauge. What is digital readout reporting for temp?
Your owners manual will have also more information about the use of the digital info center.
Just slightly above half is normal if U are stuck in traffic lets say and temp should drop back a bit once the rad fans kick in.
Also if it is not PCM or electrical -Possible the analog speedometer needle became uncalibrated? .it could be replaced or taken out and serviced. There is a company that rebuilds em just dont have link handy.
Hope this helps!
And also Welcome to the forum Katelyn!

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