Hi guys my names Aiden & I own a 1993 Honda Del Sol S.

Since I bought the car my speedometer has been reading way slower than my actual speed.

My GPS says 100, my speedometer says 40 Km/h

I tried changing the vss sensor, no change. I tried swapping the cluster with a used one, no change.

I am running bigger tires. I put the original tire size on the car to see, it made no difference.

Stock = 175-70-13
Current = 205-40-17

What can I do to fix my speedometer?

Thanks let me know what I can do

 

How much slower is "way slower" ???

 

Like im going 70km & it says 30km..

when i start moving, the speedo doesn’t actually start moving until about 15 km/h

 

That difference is not because of the larger tire size... I suspect you have a speedometer problem. I would test this by installing a known good gauge cluster and see if the speedometer reads more accurately then.

 

Likely your new speedometer is also defective. Is the odometer close to being correct? You will lose some percent going to larger tires but not 50%.

The speedometer head is actually a rather complicated bit of electronics that is mostly digital, so there's nothing to adjust or calibrate. It does have a couple of electrolytic capacitors that will fail over time though, and often capacitor replacement is all that is needed.

 

Is code 17 thrown?

 

No code 17.. I did some more testing. The VSS is putting out a pulsing voltage when you turn the wheel. I have continuity from the VSS sensor all the way to the speedo. I also have power and ground to the speedo.. theres only 1 thing it could be right?

 

This is the tachometer procedure, so if you can find the formula for the speedo, the procedure should be the same.

https://honda-tech.com/forums/honda-...epair-3336440/

 

It seems like 90s Hondas/Acuras tend to read 5mph slower than GPS on the highway.