scarlemthug

Where is the vehicle speed sensor located on a 92 cx hatch? I just went over to blockbuster and on my way home my speedo started jumping around, then just going dead, then come back to life so im guessing theres a loose connection somewhere.

zeeman

iTrader: (1)

check the wiring in the distributor as well.

bbarbulo

iTrader: (2)

that's for the tach zeeman

the VSS is on the top part of the tranny, it's like a mini-version of a distributor almost when you take it out.... like it's a long shaft and a gear at the end.

scarlemthug

would that cause the speedo jumping around or what else could it be?

imported_ryanhook

Most likely on a 5th gen it's your speedometer itself. It's apparently a common problem. Mine went on my 93 a few months ago. I had to pull apart the dash and replace the speedo. I had already replaced the VSS expecting it was that... but that'll usually produce a CEL.

The other possibility is that it's condensation on the VSS itself... had that happen too. Take the plug off the VSS and look for water build-up in it. It happened to me. I packed the part in switch lube and made sure it was water tight -- no problems since.

bbarbulo

iTrader: (2)

wow you're back! welcome back y0

imported_ryanhook

Thanks Bruno!

scarlemthug

can i test the speedo with just a small battery or how does the speedo get its signal?

imported_loudsubz

look it up in the helms

as i have no helms on my laptop so I can't comment on the signal, although its probably TTL

bbarbulo

iTrader: (2)

VSS test:

yellow/blu against the black should give 12 V when ignition is ON
yellow/white against ground should give appx 5 volts
then if those are both true.... then

jack up car and call a buddy

then turn the wheels by hand and have ur buddy watch the voltmeter to make sure the VSS yellow/white wire pulsates 5V

bbarbulo

iTrader: (2)

BTW, I never asked the obvious.... does the odometer work??

scarlemthug

ill check to see if it works, would that rule out the VSS?

bbarbulo

iTrader: (2)

yes

imported_kIeRaN

Im pretty sure its your VSS chris, my friends does the exact same thing where it works sometimes and jumps around and whatnot, they can be changed in like 2 mins Or you just may need to clean it out

imported_Cablerat

Faulty VSS should throw a CEL

bbarbulo

iTrader: (2)

they SHOULD... but here is the thing... normally the car knows its in gear and moving because VSS signal is compared against RPM, so it knows the car is moving, and it knows what gear it's in. But if VSS is NOT working... ie. it has 5V but it's not pulsing... then I don't think it can know that the car is moving any other way... unless it has ABS, and it checks the ABS wheel sensors?? which I doubt. So CEL may or may not be present. Of course... it COULD check engine load I guess through MAP, but I doubt that it does.

scarlemthug

K so after driving the car today when the needle dies the odometer doesnt work, which isnt a bad thing. Also the needle is fine until the temp gauge starts to go up, thats when the needle starts to get a little messed and then when its completely warm it stays dead.

so i need a new VSS?

scarlemthug

Also my idle is going slightly down and then back to normal, if when idling i rev the engine it seems to idle better but if i just come to a stop and idle it goes downthen back to normal. Any ideas?

imported_loudsubz

take it to a shop

scarlemthug

im taking it to my mechanic soon to get an oil change but im looking for some ideas on why my idle is slightly messed up.