Vehicle speed sensor

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evolutionmovement
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Vehicle speed sensor

Post by evolutionmovement »

Was driving last night and after a few minutes over 80 mph, the CEL came on. When I slowed way down for a rotary it went out and didn't return until I was cruising at over 80 again. Went away on its own after another few minutes at relatively steady speed. Pulled the code under Read Memory to find 33 - Vehicle speed sensor. There are no driveability problems with this whatsoever - the car's running better if anything. Should I be worried about this becoming an issue in the future (like causing poor idle and take off from idle, perhaps?) or should I just leave it alone. CEL doesn't come on driving in traffic and speeds up to 50 to work and back. I don't feel like going through all the checks with a meter if I don't have to. Anyone have this issue before?

Steve
Midnight in a Perfect World on Amazon or order anywhere. The first book in a quartet chronicling the rise of a man from angry criminal to philanthropist. Midnight... is a distopic noirish novel featuring 'Duchess', a modified 1990 Subaru Legacy wagon.
Legacy777
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Post by Legacy777 »

do you have an auto?

Over time, and if you continue to have problems with it, it will probably affect the shifting of the auto tranny.
Josh

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1990 Legacy (AWD, 6MT, & EJ22T Swap)
2020 Outback Limted XT

If you need to get a hold of me please email me rather then pm
evolutionmovement
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Post by evolutionmovement »

That's what I figured it was for - to help the transmission determine shifting, but I have a manual. Still running fine, but the FSM says it can cause idle trouble. There was a slightly eratic idle at start up this morning, but the CEL wasn't on. Guess it's no big deal.

Steve
Midnight in a Perfect World on Amazon or order anywhere. The first book in a quartet chronicling the rise of a man from angry criminal to philanthropist. Midnight... is a distopic noirish novel featuring 'Duchess', a modified 1990 Subaru Legacy wagon.
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Post by vrg3 »

I think the ECU also uses the VSS to decide when to turn on the radiator fan. If that functionality fails, it could be a big deal.
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evolutionmovement
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Post by evolutionmovement »

Right. Forgot to mention the fans... Been keeping an eye on the temp all along (like pilots scan instruments) - below half mark as usual. It seems to take a hell of a lot to overheat these cars anyway.

Thanks.

Steve
Midnight in a Perfect World on Amazon or order anywhere. The first book in a quartet chronicling the rise of a man from angry criminal to philanthropist. Midnight... is a distopic noirish novel featuring 'Duchess', a modified 1990 Subaru Legacy wagon.
Legacy777
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Post by Legacy777 »

yeah forgot about fans too......mine were on all the time when my sensor was out, and it does affect idle some too.
Josh

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1990 Legacy (AWD, 6MT, & EJ22T Swap)
2020 Outback Limted XT

If you need to get a hold of me please email me rather then pm
fishbone79
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Re: Vehicle speed sensor

Post by fishbone79 »

I know this is a long dead thread, but good info:

My speedo broke on Tuesday, no signal from the VSS caused CEL, fans to run constantly, weird idle (very high when cold, low when warm), random stalling and loss of power. This bad boy fixed the problem: http://www.main.experiencetherave.com/s ... lebase.jpg

Never would have thought the VSS could make the car run like such complete crap.
Cheers,
morgan

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1946 Ford 1.5 Ton Truck (The Beast): http://community.webshots.com/user/fishbone79
sobe_death
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Re: Vehicle speed sensor

Post by sobe_death »

Is that the transmission end of the cable?
fishbone79
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Re: Vehicle speed sensor

Post by fishbone79 »

Yes, but it's a separate piece from the cable.
Cheers,
morgan

1992 Legacy BF
1946 Ford 1.5 Ton Truck (The Beast): http://community.webshots.com/user/fishbone79
SaltyBeefCubes
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Re: Vehicle speed sensor

Post by SaltyBeefCubes »

Welp have somewhat if an update. I got all the gauges (gas,rpms, temp) to all work. However the
Mph and the odometer are still inoperable and the trans still won't shift out of first on its own. Are these by any chance related still?
Legacy777
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Re: Vehicle speed sensor

Post by Legacy777 »

Yes I would say they could be related. The speedometer is driven by a cable from the transmission, which in turn drives the odometer. Check to make sure the cable is not broken. There is a base piece on the transmission that typically breaks, and is pretty cheap & easy to replace.

Here's a picture of it.

http://www.main.experiencetherave.com/s ... lebase.jpg
Josh

surrealmirage.com/subaru
1990 Legacy (AWD, 6MT, & EJ22T Swap)
2020 Outback Limted XT

If you need to get a hold of me please email me rather then pm
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