2006 XC70 very cold weather: P0026 & P0027

[Herb Goltz]

My 2006 XC70 had a check engine light pop up this week while the kids were driving it. It has been very cold-- >-20C frequently. Since it was cold out, I just did a quickie scan with a generic bluetooth dongle rather than dragging the laptop outside and firing up VIDA.

It shows P0026&27, intake & exhaust control solenoids. The car has low miles for its age, it just rolled 160K km (~100K mi) a while back. The oil was due for a change and was down half a quart when I checked it. I had the oil done today and turned off the light.

It is running great, no degradation in performance is evident. Should I be worried about the solenoids? Should they be removed and cleaned out?

[abscate]

You just cleaned them with that oil change. Keep that interval 5000 miles with synthetic

I’m guessing the kids shuttle short trips??

[jonesg]

Mine does the same thing, it's my change the oil warning.

[Herb Goltz]

You just cleaned them with that oil change. Keep that interval 5000 miles with synthetic

I’m guessing the kids shuttle short trips??

Yes, typically out spending their inheritance on bubble tea! Glad to hear that others see these codes without immediate catastrophe-- I do have one solenoid kicking around here from my last u-pull day before things got cold for when the day comes, they are kinda pricey when new and OEM...

[- Pete -]

I don’t know if I would be worried, but I certainly wouldn’t be non-chalant about those codes. These are not an oil change reminder & could be clues that there is work needing to be done. If it was me I would absolutely change the oil/filter at abbreviated intervals (initially) & monitor closely (sounds, vibrations, odd idling, shudders, anything abnormal).

As Abscate said, it would be very wise to tighten up your OCI’s, especially if the car is being run short cycles between cool-downs. Use appropriate weight oil for your climate; I run Rotella T6 5-40 year round & pre-heat my oil pans in winter prior to startup (unnecessary, but 63ish degree oil = better than -20-30F).

Worst case scenarios -
1. Oil pan needs to be dropped, cleaned & new seals/o-rings installed.
2. PCV is clogged & crankcase pressure is making its way to the valve cover (air getting into VVT solenoids).
3. VVT solenoids are actually bad (highly unlikely that both croaked).

Best case scenarios -
1. Everything will work itself out with shortened oil changes.
2. PCV system overhaul.

Don’t pull your VVT solenoids just yet, though. Run a couple changes of oil through it first & observe closely it’s behavior. I don’t intend to freak you out, but I do think it’s smart to acknowledge & understand red flags when they pop up.

Edit: corrected my neglect for acceptable Oxford comma & semi-colon etiquette.

[Herb Goltz]

Thanks, this is solid advice! I haven't done a glove test on this car yet, my kids have been driving it since I bought it in August '20 with about 83K mi on it, it has gone about 20K mi more since then, so not a high-miler. It belonged to an 84 year old man before I bought it, but I don't know much about the maintenance history-- apparently the guy's son was some kind of fleet mechanic and he did the maintenance at work. Will up the oil changes on it for sure!

[- Pete -]

Snip… It belonged to an 84 year old man before I bought it, but I don't know much about the maintenance history-- apparently the guy's son was some kind of fleet mechanic and he did the maintenance at work.

I bought one of these kinds of cars a few years ago. The low miles and the fact that the old guy kept it so pristine tickled me. The thought that it was literally never revved high or driven hard was impossible to ignore & very alluring. The sad part was it was driven 2 miles to town, then 2 miles home. At the time, I had no idea this type of use in P2’s is detrimental. This was the course of its life for around 40k miles, oil changes done every 7,500-8,000 miles (according to his records).

I quickly learned that this is a recipe for disaster in these engines. They need to get hot and be driven mild-hard frequently. In my case, I happily drove it home (200 miles) from the sale & promptly got a “NO OIL PRESSURE, STOP IMMEDIATELY” message in the DIM. When you see this, you DO THIS.

I spent the next few weeks becoming educated by MVS members and educating myself as to the extent of the repercussions of long OCI’s & short drive/heat cycles on P2’s. Long story short, it took a lot of work to save my investment, but I’m very glad I heeded the advice & warning signs given to me.

Amongst a lot of other things, I ended up replacing the entire PCV system, dropping the oil pan for cleaning and replaced every replaceable seal/gasket & pickup tube.

I sincerely hope you can skate by with doing some shortened OCI’s, but I also want to be informative enough that you get a real good look at what reality might have in store for you.