Greetings! I'm new here on the forums and have just recently purchased a 1990 Formula 5.0 TBI with 5 speed manual transmission, I just got the car delivered today all the way from Ohio sight unseen! I have a lot to say about this car but it's in fairly good condition with less than 20k miles on it, this hasn't spared it from the usual failures you see in older cars, wiring has been messed with and an awful aftermarket alarm installed (carfax reports it was stolen in 1991 so I'm guessing this is a result of that incident). The usual things like the hood and hatch struts are collapsed, coolant is leaking somewhere and all the usual little bits of rust starting to poke through. I'm starting to digress, I'm in Southern California and of course the first thing I did today was take it in for a smog test... On the way to the smog test I noticed two things, firstly when idling, the revs seem to pulse between 1k and 500 rpm, it's like it's hunting for the correct idle speed, secondly the "Shift Up" light was coming on at the wrong time, at mid to low rpm (I'm guessing it should only come on when you're revving the **** off of the engine) and either this car is incredibly fast or it's mis-representing the speed as it feels as if I'm going 45 when it says 60. At the smog station the technician ran the tests and it failed spectacularly! Turns out the Catalytic converter was removed... Awesome, 350 bucks for a magnaflow "carb approved" replacement from Autozone which is on the way, that should hopefully fix it since the rest of the smog stuff still seems to be there. However on the way back from the smog station the "Service Engine Soon" light came on and after jumpering the pins, I got a code 24 "VSS error" code. I climbed under and took a few pictures, there seems to be a bad seal from the VSS sensor (at least it looks like that's where the ATF? is leaking from), The fact that I'm still getting a speedo readout tells me that the sensor is at least sort of working? Has anyone had any experience with this sort of thing? I can unplug the battery and reset the computer before the test and the light may not come on, but I'm not the cheating sort and I'd like to resolve the issue, has anyone encountered this sort of thing before? I'm thinking it's possibly the gear inside the transmission that's attached to the VSS that's wrong.

Less than 20k!



Tomorrow I'll crawl under there and clean up that mess and try to pull it out, I also have all the rpo codes and it looks like everything is bone stock other than that annoying alarm system and maybe this vss sensor, any advice would be appreciated. Also it says use dextron II, I'll probably use dextron III as I read somewhere here on the forum that it's totally fine to use that too.

P.S. This forum is fantastic, I have found answers to most of my questions just by searching, I'll make sure that once I have this all sorted that I post the solution here.