CVVT Codes, trans slipping?..

[Larry_Dean]

Hello,

I have a 99 S70 awd turbo auto trans 195,000 miles. I was driving home from work and as i came to a stop from getting off the highway, the car was acting like it was in 3rd gear(best way to explain it). Drive and reverse do not have the up shift light but 3rd and low do. The car will rev and creep slowly around 2 3k rpm. I got it home and the codes read were
P0134 02 sensor circuit no activity detected bank 1 sensor 1
p0036 heater control circuit bank 1 sensor 2
P1332 CVVT Solenoid
P0013 B cam position actuator circuit/open bank 1
I drove 3500 miles with p0134, p0036, and p0013 on. I replaced the solenoid with a junkyard one, and a brand new upstream oxygen sensor. Do these codes have any correlation with the trans issue? Thanks

[Larry_Dean]

Also, reverse has been acting up for the last 2000 miles before this happened. It revs sometimes and will slowly creep, and sometimes it will work fine with a little bit of a jerking, nothing major but it seemed off.

[FlyingVolvo]

Have you checked the transmission fluid level? Also, when was the last time it was changed? If it's black or smells burned, that would be a bad sign. Those transmissions are pretty solid, but bad fluid will take its toll. Personally, I would drain/fill the transmission with a quality ATF a couple times (my go-to is Mobil 1 Syn ATF, pricey but worth it). Then disconnect the battery, reconnect and see what codes reassert. Might also help reset the transmission shift logic a bit.

[Larry_Dean]

The fluid level reads slightly above the hot full line when it is hot. The transmission fluid doesnt seem burnt or really dark. I wouldnt say its bad, but its been used for a while now im sure. I thought, because of the clutch material that is usually in the fluid, that is it a bad idea to drain and use new fluid? Or do you mean drain, refill, drain, refill with the old fluid? Thanks for the reply.

[FlyingVolvo]

Yeah, so there's a lot of opinions on the best way to replace ATF. I think the general consensus is that a series of drain and fills is the best way to transition to mostly new fluid. That is, drain the fluid (appx 3.5 quarts will come out) and refill the same amount with new, drive a little bit, then repeat the procedure until you feel good about it (usually 3 times total). Most people will suggest avoiding any shops that "power flush" the transmission.

Not sure about the clutch material in the fluid... but it's perfectly safe to replace old fluid with new, so long as the new stuff is meeting the right specs. Volvo advertises their ATF as "lifetime", and it's true... by reducing the lifetime of the transmission! I switched over to Mobil 1 Synthetic ATF and also installed both an aux cooler (in addition to the cooler integrated in the radiator) and a Magnefine transmission filter. I credit all of that with keeping my trans happy through high heat, heavy loads, and towing conditions that I put it through fairly regularly.

Best of luck with yours. Hopefully others will chime in about your situation. Being stuck in 3rd gear sort of also sounds like maybe a PnP switch issue, but I'm not positive on that.

[Larry_Dean]

I wish i couldve done the same, but when i got her she was a parts car for years. The entire rear end is now a v70 and replaced a bunch more on her. I will do the 10qt drain and fill. I appreciate the help. I will also look into the pnp switch if anyone else comments. I tried doing the shifting from P to Low dozens of times. Seems to help a tiny bit. Not noticeable really.

[FlyingVolvo]

Sounds good. I would still try disconnecting the battery after at least the first drain/fill to try and reset the transmission computer. I like to try easy stuff first!