[size=7]I have a 1994 Honda Civic DX that is having a problem with either its speedometer or some other part of its speed sensing circuit. The speedometer shows speeds all over its gauge (and sometimes has even pointed straight down). When it does move (and it doesn't always while I am driving) the motion is not smooth but jittery. Sometimes it will jump up and show I'm doing 100 or more mph but seeing as I'm the slowest car on the road at the time I know the reading isn't even close. I can set the cruise control and it will keep the car at an even speed. When cruise is engaged the speedometer will sometimes hover around a constant reading (which I can tell by the flow of traffic isn't correct but the reading is more or less stable) but other times the speedometer will fluctuate by 15 or more mph. I replaced the speed sensor because most people I talked to (even the Honda dealership) said that was most likely the source of the problem. When I took the old speed sensor off it was filthy inside with what looked like some kind of grease. When the new speed sensor went on the problem seemed to disappear but by the next day the speedometer was back to being erratic. I don't know if the new speed sensor fixed the problem temporarily or I was just lucky. I can't even be sure it was accurate during this time but it wasn't erratic like it often was before and is again. I also haven't opened up the replacement speed sensor to see if it is now filled with that thick "grease" too. Since I replaced the speed sensor and the problem remains I am looking for some other ideas before I change out more components. Yes, it could be a speed head gone bad but are there any other possibilities that I should check out before getting a replacement speed head. Everyone swore it was the speed sensor so I replaced it but it would seem they were all wrong and I would prefer not to just blindly continue replacing components.

I've got a '96 cx with the same problem... i just replaced the instrument cluster, and it was good for a day as well. it started cutting out again tonight.
mine's the version after yours, but i can't see it being completely different inside. if i figure out my problem, i'll come back on here and let you know - i'm going into work first thing in the morning to check everything out.

is your check engine light on? if check engine's on, you might be able to run codes on it and it may tell you what's malfunctioning.

We had a car with the check engine light on it. We ran some codes on it to find out what the problem was. The mechanic did narrow it down in finding the problem.

Alright, so I took my sensor off today - same grease inside of it. So as soon as i find one, I'll be replacing it.
Just a question though, mine has the sensor part which is attached to the tranny, and then the plug that comes out of it as well. Did you change just the part in the tranny or the whole thing - plug included?
I'm going to be taking a plug off a wiring harness my friend has sitting around for his old car, but putting in a new sensor... maybe the plug is the common factor in your problem?

Also, maybe there's a fuse blown from before you changed it that needs to be replaced? I may be waaaay off here, but I noticed that the wacked out speed sensor has been blowing my 7.5 amp fuse in the under dash box (number 15 fuse) which connects to the alternator and a bunch of other things.
Maybe get at your fuse box and see if anything's blown under there.

The cool thing that I've learned about running codes is that there's a big long system that tells you exactly what the code means, how to test it out to find out what's causing the code, and then how to fix it. I know that here we have a program called "Mitchell" which goes through the whole diagnostic and repair process... your shop probably has something along the same lines.

I don't know if the grease inside the VSS is nomal or not but the new VSS out of the box was clean as was the VSS on my other Civic (95) which I opened up for comparison. I replaced the whole VSS which is bolted to the trans with two aluminum bolts but the plug that connects into the top of the VSS I did not replace.

The check engine light has never come on with this problem and no codes are given when I request them (I tried just in case).

The cruise control does function correctly and hold the car at a constant speed. I can tell by the flow of traffic around me that the speed is probably not being displayed accurately on the speedometer but it is constant. Sometimes the speedometer will also reflect a constant speed with cruise on and other times it will vary by 10 to 15 mph with cruise on. In both cases the car does maintain a level speed.

My assumption is the problem is not with the VSS since I replaced it and the problem remains unless it is a problem elsewhere that trashes the VSS. Is that a possibility? This thing spent two weeks at a repair shop and they were never able to pin it down, but they did admit to me that they saw it. I'm open to any suggestion about what else to do to try and pin point where the faulty component/wire is.

This post has been edited by big O: Dec 13 2007, 09:13 PM

hey i was reading about your problem and had to create an account to answer your question my car did the exact same thing i changed the sensor completely i put in a new cluster and still had nothing it did everything yours is doing until it finally stopped moving period. recently i pulled the trans to put a clutch and flywheel in and ended up putting in a vx trans with longer gears and put the same vss in i ahd the my trans and after the new tranny(well used) my speed works all day every day no problem. it might be the same for you i kno i looked and looked for ever trying to figure it out andjust by chance i did. but if its not a problem just change your trans out and see what happens.

if they checked it out i can almost garantee its in the tranny and a d series tranny should cost that much maybe 50 bux on one of your street racing forums i live in cincinnati and i find all mine on cincinnatstreetracing or cincystreetscene.

good luck hope this helps

i have a 2000. i replaced the speedometer sensor to no avail then a new battery also a waste. then checked the wiring not a problem. then off to a junkyard for a actual speedometer part or cluster as they call them. by the way a cluster at a junkyard cost me like 35 bucks and the shipping on one from the net is like 15 bucks. I had a dealer check that speedometer sensor for free so do that before you replace it. It by the way can be changed in like 10 minutes. The speedometer cluster has 6 screws and takes about 5 minutes to change. i changed mine and all was well. but as i did not like the new miles racked up on the replacement i had taken the face off the cluster. take out the four screws on the back of the speedometer part and you will find a 3 inch size computer board that plugs in easily. I change the new one from the junkyard to the old one with the correct miles and whala all is great!!!!! now i have an extra tach and bulbs and such for later which was tonight i found out. personally i'd go here first.