Joined: Feb 2019

Posts: 27

Likes: 0

From: Oklahoma

so yeah. Tach not working at all. Speedo works once in a while. Like it’ll run maybe one of out of every 10 starts and only for about a mile or two. Then it’s dead. Odometer only works when sleep works.

I have no clue what’s causing it. I pulled the Soeed sensor on the tranny and it came apart. It wasn’t old as hell. Replaced it with a new one. No change with the new part.

note. Started happening when I dropped in. An new chipped p28. Had a stock p2t in and the car when it was purchased and it was way out of tune, CEL was on and couldn’t pull OBD 2 codes. So I went OBD 1 instead. Tach and odo issue started after the P28

Joined: Mar 2008

Posts: 5,474

Likes: 46

From: Salem, Or

It's pretty common. You have to run a wire from the blue wire on the distributor the rpm output to the single wire on the chassis harness on the driver side shock tower. That will fix the tach. As for the speedo it's almost always corrosion on the vehicle speed sensor plug its self. Inspect it closely and clean it with a wire brush and add some dielectric grease on the contacts. If any are broken then you'll need to cut a good plug off another harness and solder it on

Joined: Feb 2019

Posts: 27

Likes: 0

From: Oklahoma

I know where the distributor is. I have not idea what you’re taking about in the second half. Do you have a picture of the wire on the shock tower?

Joined: Feb 2019

Posts: 27

Likes: 0

From: Oklahoma

Joined: Feb 2019

Posts: 27

Likes: 0

From: Oklahoma

I replaced the speed sensor pigtail using your instructions. Speedometer works, odometer doesn’t. Any suggestions? Where to check next? Wiring was reconnected exactly the same.

Joined: Feb 2019

Posts: 27

Likes: 0

From: Oklahoma

Speedometer went on the fritz again. I had an Si cluster get delivered today. Installed that and now the speedometer, odometer and trip meter all work,

but now my RPMs are reading about 1000 higher than actual number. VTEC is set to kick in at 4500, looks like 5500 on the Si Cluster. Shift light comes in at 7500 (I react slow, I need the extra 700 rpm), but it’s kicking in at around 8500 on the Si cluster. RPMs sound normal, it’s just reading wrong. I’m gonna do some research on the forums this week, but if any of you know the answer, please just let me know.

Joined: Mar 2008

Posts: 5,474

Likes: 46

From: Salem, Or

One of my buddy's told me you can adjust how the tachometer reads by something on the back of the cluster, i believe he said it can be messed with using a philips head, if you figure it out post some pics as I'm curious as well. As far as I've seen allot of the tachometers read differently from one Honda to another. They aren't the most accurate pieces.

Joined: Mar 2008

Posts: 5,474

Likes: 46

From: Salem, Or

https://m.youtube.com/watch?v=K_midzf1uXo