How do you read timing in VIDA?

[jonesg]

[erikv11]

Fuel pump looks fine in VIDA.

Ironically the fuel pump in the S60R (different car, not this thread) started crapping out last week and that Pine Hollow fuel pressure video was perfect to diagnose. ECM-2900, almost an exact match to the video. So I'll be replacing that one, but no apparent fuel issues in the XC70.

So the 07 XC70 still has a steady, mild chug, everything else seems fine. No codes. If I can find time to re-time it this week I will, otherwise it goes to the shop on Friday.

[erikv11]

Report from Thursday (two days ago):

Put the crank on the mark, took it apart, put the cam tools one, pulled the timing belt: both VVTs were fully clockwise, timing was perfect. So I left the timing alone and put it back together.

Drove it, still had the annoying, minor chug.

Checked the STFT, LTFT, both looked fine, so presumably no hidden O2 sensor problems. O2 sensors are original (180k).

Pulled the MAF and saw that the filament was visibility dirty (pics to come). Cleaned it, reinstalled, took the car out for another drive - better! Still seems imperfect but much better, no chug at idle and engine is smoother.

So canceled the shop appointment for Friday morning, back to driving it now.

[jonesg]

Report from Thursday (two days ago):

Put the crank on the mark, took it apart, put the cam tools one, pulled the timing belt: both VVTs were fully clockwise, timing was perfect. So I left the timing alone and put it back together.

Drove it, still had the annoying, minor chug.

Checked the STFT, LTFT, both looked fine, so presumably no hidden O2 sensor problems. O2 sensors are original (180k).

Pulled the MAF and saw that the filament was visibility dirty (pics to come). Cleaned it, reinstalled, took the car out for another drive - better! Still seems imperfect but much better, no chug at idle and engine is smoother.

So canceled the shop appointment for Friday morning, back to driving it now.

it makes sense that in the absence of a timing fault code... its not that.

[erikv11]

Sure, yet it makes no sense that it ran poorly without a code, or that it went from throwing VVT codes to having a MAF issue …

Here’s before and after for the MAF filament:

MAF before cleaning, 180k

IMG_4452.jpeg (127.74 KiB) Viewed 349 times

MAF after cleaning

IMG_4454.jpeg (97.3 KiB) Viewed 349 times

[abscate]

That’s a dirty MF….wait,,,,MAF.

I think that’s potato residue

[xHeart]

That’s a dirty MF….wait,,,,MAF.

√ approved for subject line!

[erikv11]

Still had an annoying low level engine shake. Looked and looked but haven’t found any vacuum leaks. So I swapped front oxygen sensors with the other XC70; engine is now much better, did more than cleaning the MAF. Like butter at idle, big difference there. Ordered a new Bosch sensor, going to put it in this weekend.

This O2 sensor appears to be original, based on pretty exhaustive records that came with car from previous owner. We’re the second owners.

[dono]

VVT is new Volvo branded, bought from FCP.

Was super careful with the VVT rotation triple checked it etc., but I will check it again when I take it apart this weekend.

Did not lock the crank but had the harmonic balancer off, very sure it stayed on the mark.

Back of the cams did not break. Yet.

Those CAM hubs are tightened to 120Nm so when you loosen (or tighten) with that level of force Im not certain how you can do that without moving the cam shaft out of timing. Love to know if/how you ever found vida dice procedure for timing and cam adjustment...

[dikidera]

I did not tighten mine to 120nm, was too scared for something to snap.