1995 speedo problem
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1995 speedo problem
i have a 1995 lt1, running 275/40zr17 front and 285/40zr17 in the back. the problem is it reads about 20mph high at 80mph. so at 80 it reads 100mph. i thought it was the aftermarket tires and rims but im not so sure. i heard it might be the cluster it might be the speed sensor. its done this since i bought it so ive never seen it work properly. any ideas what it might be and how to fix it would be a great help.....hans
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im not sure....i bought the car a week and a half ago. what whould be the easiest way to tell? its a auto and around 80mph im running 3000rpms.........it would make sence tho....i would think the rpms would be lower at that speed in overdrive.
Last edited by shhaker69; Feb 14, 2009 at 10:08 PM.
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From: Slidell Louisiana
i have a 1995 lt1, running 275/40zr17 front and 285/40zr17 in the back. the problem is it reads about 20mph high at 80mph. so at 80 it reads 100mph. i thought it was the aftermarket tires and rims but im not so sure. i heard it might be the cluster it might be the speed sensor. its done this since i bought it so ive never seen it work properly. any ideas what it might be and how to fix it would be a great help.....hans
Is it reading metric? If not reading metric and an A4 the speedo can be set via tuner cat or other tuning software, if its reading metric hit the eng met button on the dash and get it back to back to mph .
Looking at my tuning software the M6 should be similar, but I don't have personal experience with a 95 M6 car.
Last edited by aboatguy; Feb 14, 2009 at 11:45 PM.
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naw....its not metric. definatly mph. whats the stock gearing in that car? and if it does have differnt gears is there a way to fix the speedo or do i have to live with it? i do alot of freeway miles and i would kind of prefer a taller gear but?? i swapped gears in my 04 mach 1 and i used a diablo to fix the speedo.
Melting Slicks
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From: Austin Texas
i have a 1995 lt1, running 275/40zr17 front and 285/40zr17 in the back. the problem is it reads about 20mph high at 80mph. so at 80 it reads 100mph. i thought it was the aftermarket tires and rims but im not so sure. i heard it might be the cluster it might be the speed sensor. its done this since i bought it so ive never seen it work properly. any ideas what it might be and how to fix it would be a great help.....hans
I would just leave it alone and impress my friends !!
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It sounds like they've changed the rear end from the 2:5x to a 3:07. Jack up the rear of the car and turn the drive shaft in neutral. the number of times the drive shaft turns to one revolution of the tires is your ratio. Then check your glove box for the option code.
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ya my buddy took it for a spin and he said wow i got up to 75 so fast. and it did even feel like 75!!! i just left it alone........lol
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From: Slidell Louisiana
When I had my PCM cal'd for the wrong gears it popped codes (it was 3 or 4 years ago I don't remember the codes I think it was antilock or ASR related due to the speed mismatch)
Which is why I asked about eng/met button, too bad that wasn't the problem.
Are you getting any codes?
How long have you had the car?
Auto or manual transmission?
Whats it do when you hit the eng/met button at 80 mph?
Mike
Last edited by aboatguy; Feb 15, 2009 at 11:25 PM.
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When I had my PCM cal'd for the wrong gears it popped codes (it was 3 or 4 years ago I don't remember the codes I think it was antilock or ASR related due to the speed mismatch)
Which is why I asked about eng/met button, too bad that wasn't the problem.
Are you getting any codes?
How long have you had the car?
Auto or manual transmission?
Whats it do when you hit the eng/met button at 80 mph?
Mike
no codes
2 weeks
auto
switches to metric
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From: Slidell Louisiana
Le Mans Master
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From: Woodstock Georgia
Check the rpo codes under the storage compt lid behind the passenger seat for the factory rear end ratio. There were two options, GM1 was the stock 2.59 ratio which gives 80 mph at approximately 1800 rpm, the G44 option (I think that is right) is the 3.07 ratio which translates to 80 mph at about 2100 rpm. Any ratio change has to be programmed into the PCM, not by changing any senders. Hope this helps.
ps-your rear tires are the stock size
ps-your rear tires are the stock size
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wow, i thought 3000 rpms at 80 was high. I had a 04 mustang mach 1 and in 5th at 80 i was running 1800 or so. but my 350 z i run 3000 at 80mph in sixth gear. i will jack it up in the am and check it out. it shifts from 1st to 2nd real fast and it hits hard. not too hard, if feels good but like it has a shift kit in it.