'90 Speedometer Intermittent
Thread Starter
Instructor
Joined: May 2006
Posts: 180
Likes: 11
From: Colorado Springs Colorado
'90 Speedometer Intermittent
Recently bought '90 and everything worked fine. After about 3 months noticed the speedometer stayed at 0 as I was accelerating, then would catch on and run up to 25 then back to 0 a time or two then catch up to 35 (which was the right speed) and be ok.
It has gotten progressively worst and now stays at 0. Ocassionally when on the freeway doing 70, it will move off of 0 an run back and forth between 0 & what ever speed I'm going. Sometimes settling out at the correct speed and sometimes just going back and staying at 0.
I would like to fix or get it fixed, any idea?
thx
rick mendoza
It has gotten progressively worst and now stays at 0. Ocassionally when on the freeway doing 70, it will move off of 0 an run back and forth between 0 & what ever speed I'm going. Sometimes settling out at the correct speed and sometimes just going back and staying at 0.
I would like to fix or get it fixed, any idea?
thx
rick mendoza
Team Owner
Joined: Sep 2002
Posts: 22,209
Likes: 12
From: OBAMA IS HITLER
you have what is most likely a bad tachometer filter. its a silver cylinder mounted at the rear of the left cylinder head. i don't believe you'll find a new aftermarket replacement for 90/91. try a salvage yard. thats what i did, and my tach has returned to full functionality. if this doesn't work, then the most likely cause is a bad ground in your instrument cluster. try the tach filter replacement first; a used one will run you about $30 since the part has been discontinued without replacement.
try: www.corvettesalvage.com
try: www.corvettesalvage.com
Thread Starter
Instructor
Joined: May 2006
Posts: 180
Likes: 11
From: Colorado Springs Colorado
Thanks Brad,
I will keep that info about the tach fillter. In fact on one occassion my did fluxuate a little and sometimes when I turn it off, the Tach pegs fully up. If I turn on the key on it will reset to 0, so I'll check that out.
However, my write-up was on my Speedometer. Please reread my write-up as you may also has some helpful hints on my Speedometer issue.
thx again
rick
I will keep that info about the tach fillter. In fact on one occassion my did fluxuate a little and sometimes when I turn it off, the Tach pegs fully up. If I turn on the key on it will reset to 0, so I'll check that out.
However, my write-up was on my Speedometer. Please reread my write-up as you may also has some helpful hints on my Speedometer issue.
thx again
rick
Thread Starter
Instructor
Joined: May 2006
Posts: 180
Likes: 11
From: Colorado Springs Colorado
90 Speedometer Intermittent
No, as a matter of fact it is no longer intermittent, it's inop! 99% of my driving is in town and 45 mph or less and it now stays on 0. Every once in a while when I get on the 405 and drive 70+ for a while it will come on and read correctly, but once the speed drops below 40 it goes to 0 again.
I don't know where the speedometer sensor is (assume the transmission) and I live in an apt, but next week I move and will have a garage. Then perhaps I will be able to address some of the minor irratants that I just don't have the facility to do now.
I assume the problem would be with the transmission, sensor, speedometer and associated wires/connectors/connections.
God Luck and God Bless
rick
I don't know where the speedometer sensor is (assume the transmission) and I live in an apt, but next week I move and will have a garage. Then perhaps I will be able to address some of the minor irratants that I just don't have the facility to do now.
I assume the problem would be with the transmission, sensor, speedometer and associated wires/connectors/connections.
God Luck and God Bless
rick
Instructor
Joined: Jun 2004
Posts: 249
Likes: 0
From: clinton ut
Speedo inop
I just fixed the same problem with mine. My wife is downloading some photos right this minute so when she is done I can show my problem. It was a bad connector that plugs into the transmission sending unit. Also a pic of the filter capacitor.
Drifting
Joined: May 2002
Posts: 1,562
Likes: 1
From: "Drive like Hell, you'll get there faster." Tucson AZ
Originally Posted by eptaylor
I just fixed the same problem with mine. My wife is downloading some photos right this minute so when she is done I can show my problem. It was a bad connector that plugs into the transmission sending unit. Also a pic of the filter capacitor.
I'm also having the same problem with the speedo on my 90. Its goin crazy after driving for a while showing all sorts of readings until I stop or accelerate at high speeds. Been doin this for the past 2 days. I did just have a new tranny put in about 2 weeks ago so it makes sense.....the whole connector thing. I'm gonna have my tranny ppl check it out. I'll keep everyone posted.
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Instructor
Joined: Jun 2004
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From: clinton ut
Speedo Re-visited
I just installed a new flex-plate and torque converter. Speedo worked goofy afterwards. I pulled the electrical connector to the sending unit on the transmission and it was busted/melted. Replaced connector with a CARQUEST part # S712 for $18.00. Fixed my speedo problem. I should have seen the bad connector in the first place but did not. Included are pics of my UGLY connector. P.S. this is about all I know about speedo problems.
Notice on this pic the plastic tubes that cover the metal prongs are GONE!
Notice on this pic the plastic tubes that cover the metal prongs are GONE!
Team Owner
Joined: Sep 2002
Posts: 22,209
Likes: 12
From: OBAMA IS HITLER
Originally Posted by rmendoza
Thanks Brad,
I will keep that info about the tach fillter. In fact on one occassion my did fluxuate a little and sometimes when I turn it off, the Tach pegs fully up. If I turn on the key on it will reset to 0, so I'll check that out.
However, my write-up was on my Speedometer. Please reread my write-up as you may also has some helpful hints on my Speedometer issue.
thx again
rick
I will keep that info about the tach fillter. In fact on one occassion my did fluxuate a little and sometimes when I turn it off, the Tach pegs fully up. If I turn on the key on it will reset to 0, so I'll check that out.
However, my write-up was on my Speedometer. Please reread my write-up as you may also has some helpful hints on my Speedometer issue.
thx again
rick
Last edited by Red Tornado; Jul 24, 2006 at 08:08 PM.
