Confused ATX

[eacyde]

Lately my beloved SHO has been giving me grief.

The latest issue is when I am driving between 20 & 30 mph, the trans can't decide what gear to be in.

on another occasion at 55mph it shifted down to 2nd for a brief moment and back to 4th.

My question is: is this a computer issue or mechanical?

It is a 1993 with a D4U1 computer. the trans was rebuilt approx 18,000 miles ago.

any insight will be appreciated

 

[SHOtimer]

I would say your VSS is going out.

Doug

 

[rubydist]

in my experience, either a sick vss or bad wiring to the vss will do this - the pcm gets a varying speed reading, so it shifts randomly and stupidly.

 

[eacyde]

I was messing with the shifter and I could not get 1st all the time. I would stop at a light and put it in park, then 1st and it would be in 2nd when I took off.

On a scale of 1-10, 10 being the hardest, how difficult is the VSS to change? I am pretty handy and know my way around a car.

Thanks for the help. I would probably have sold the car long ago if this forum didnt exist.

 

[rubydist]

its a B, or around 5 - not "hard" just hard to reach.

 

[eacyde]

Would a failing VSS also cause the VAPS to do strange things?

On my drive home at 60MPH the assist was the same as it should be at 5mph, then in a parking lot at 5mph there was no assist.

 

[SHOtimer]

Would a failing VSS also cause the VAPS to do strange things?

On my drive home at 60MPH the assist was the same as it should be at 5mph, then in a parking lot at 5mph there was no assist.

Yes, because the VAPS also gets its signal from the VSS.

Doug

 

[whiteguy3]

VSS or wiring to the VSS.

 

[eacyde]

I am going to replace the VSS tomorrow and check the wiring. I'll report back tomorrow afternoon.