Car runs great, then runs like crap, then runs great again.....error codes

[luxbellmyer]

My 2K V70XC has been up and down lately. It will run like normal and then bog down for a while, and then check engine light comes on. The codes are P0014 exhaust camshaft position timing over advance and P0422 main catalyst efficiency below threshold. And then it will quit bogging and run fine again. And then it will run like crap again. There seems to be no pattern to when it does it. If the timing belt was off by a tooth it would stay running crappy all the time, right? I'm really hoping it's the sensor......any help would be much appreciated.

[burnout8488]

Sounds like it might be the VVT solenoid....

...and that's all I know about that! Hopefully others can help more.

[luxbellmyer]

O.K. Stupid question time, is VVT variable valve timing? And if so, I don't think that the 2K model had it yet. Anyway, is it under the #10 part which is part #4/6? And if so, is it as simple as just swapping it out for a new one?

[burnout8488]

'99 was the first year for VVT on the exhaust camshaft.



I've never disassembled one, so the picture you posted may or may not be it. Couldn't tell ya. But, since the code is for the exhaust camshaft, it sort of leads to being the VVT solenoid. I think it's a simple fix, but also, not sure on that. Something might need to be pre loaded.

[luxbellmyer]

I've owned this car for a dozen years and was unaware that it had VVT.......I guess you learn something new everyday. Is the picture you posted of the solenoid? Looks like it should be a quick swap........I might try to reseat the old one and give a good cleaning before I order a new........this car is really something else.........if I had only know then what I know now. I got this when my wife was pregnant with our first child and I had this great plan to keep the car for her for when she turns 16. Because Volvos last forever right? My 83 245 has 300K and just runs and never needs anything. Not the crosscountry. It's been an amazing adventure through the last dozen years with this thing........a turbocharged all wheel drive Swedish tank with glass and paper parts.....and I'm not talking about the windows or the air filter. I'm still on track for my 12 year old daughter to drive this car............being OCD helps if you own a P80

[luxbellmyer]

One more thing, is the P0422 main catalyst efficiency below threshold just a by product of the exhaust cam being whacked out, going away after the cam is back in it's happy place.........hoping it's not shot

[burnout8488]

Yup! Primitive Volvo VVT

At this rate, she should be driving it in a few years, and I agree about the OCD thing. It's the only way to keep these going without a check engine light.

Cleaning it may produce good results, and is definitely worth a shot. I hear they're very picky about the cleanliness of the oil, and if they get gummed up they can fail. And yes, the P0422 can definitely be a byproduct of misfires and poor timing. I'd be surprised if it didn't go away when the solenoid is fixed.

4-8mm bolts hold the solenoid on, and the spark plug cover is held with T30 torx bolts. Pretty easy.

[luxbellmyer]

I've seen it a few times while working on things so I know it's a just few minutes job to get it.........I'm heading out now to give it a cleaning, rub down and reseating followed by a test drive........

[luxbellmyer]

Well took it apart and found that the connector was not snapped all the way in. So I cleaned it and put it back on and went for a test drive and it ran great. Now my wife can drive it around for the next couple of days and we'll see if it really made any difference...........if not, I wonder if if I should order up a new one. Hopefully it's just that simple, if it still ends up having the same problems.........

[JRL]

New ones requires a minor modification
It's an upgraded piece, the electrical connectors have to be changed