S14 Speedometer is 15mph Over...

[Driice]

Hi Guys,

I tried the search function, but came up short. I recently bought a 98 S14 and my speedometer is running ~15 mph over the actual speed. I brought it to a shop and they said I need a whole new cluster? I told them that all you probably need to do is reset the speedometer. I was wondering if there was DIY on here for that or if anyone knows what kind of shop can fix this type of issue?

On a side note, my car idles kind of high. Could this be the case that the speedometer is ~15mph over? If I fix the idling will the speedometer be normal?

:ugh:

[Brentbohn]

unless your wiring is shorted or causing interference there is no way those two symptoms are related, As far as the speedometer is concerned, do the obvious and verify you have correct wheel tire combo to yield the same rolling diameter as stock. If that is not the issue then my question would be when the car is off, is the speedo needle resting at zero or 15? if its at 15 then you are correct and should be able to pull the cluster out and take it to any auto electric service store, contact any local dealership ask who they use.

The high idle is most likely caused by a vaccum leak or dirty iac valve/throttle body or bad egr... check codes but best to spray flamible brake clean not the hippie earth friendly crap all around the hoses, intake manifold and left side of head, if the idle changes you have a leak, if not then look at gas pedal linkage see if its binding, also as years of dealing with second hand cars has taught me, look for any ANY aftermarket equipment and remove to see if it changes. Might have incorrect MAF or FPR ect... start at the basics and go from there.

Oh last thing is s14 has a circuit to bump the idle based on demand of accessories, power steering system has a pressure switch, Air Conditioning switch and it will even bump it up 100 rpm if I turn my headlights on,,,, kinda nice, its a feature to make life easier with a 4cyl.... you can disable it but I would try repairing it first.

[Driice]

unless your wiring is shorted or causing interference there is no way those two symptoms are related, As far as the speedometer is concerned, do the obvious and verify you have correct wheel tire combo to yield the same rolling diameter as stock. If that is not the issue then my question would be when the car is off, is the speedo needle resting at zero or 15? if its at 15 then you are correct and should be able to pull the cluster out and take it to any auto electric service store, contact any local dealership ask who they use.

The high idle is most likely caused by a vaccum leak or dirty iac valve/throttle body or bad egr... check codes but best to spray flamible brake clean not the hippie earth friendly crap all around the hoses, intake manifold and left side of head, if the idle changes you have a leak, if not then look at gas pedal linkage see if its binding, also as years of dealing with second hand cars has taught me, look for any ANY aftermarket equipment and remove to see if it changes. Might have incorrect MAF or FPR ect... start at the basics and go from there.

Oh last thing is s14 has a circuit to bump the idle based on demand of accessories, power steering system has a pressure switch, Air Conditioning switch and it will even bump it up 100 rpm if I turn my headlights on,,,, kinda nice, its a feature to make life easier with a 4cyl.... you can disable it but I would try repairing it first.

Thanks man! I've taken it to a couple of shops and they're looking at it. They said it might be the correct wheel tire combo, but we'll see.

[shahabshaukat]

was the diff ever changed? and at what speed is it off by 15mph?

[fliprayzin240sx]

Better yet, what size tires do you have on the back and I can tell you right off the bat if you're shit is what's throwing off your speedo.

[spooled240]

unless he's running smaller than stock tires, his speedo should be reading SLOWER than actual speed.

I have 18's and my speedo reads about 4 mph too high doesn't make sense but the speedo is out of a 200sx so idk

[s14j]

is it auto or manual? if its manual and it was converted to manual then its the speed sensor.
your probly using a s13 tranny. buy a s14 speed sensor and your problems will be solved.
had this problem before.
its answered. you should search before you start a thread.