I have removed the MA unit on my 03/2010 QV as I had rough idle and started loosing one cylinder. Fault code P0304 indicated that cylinder 4 was falling out.
Check out Ransoman's guide on removal of the unit, then I will take it from there.
I had valve actuator parts falling out of cylinder 4 unit as I lifted the MA unit off, just as Ransoman had warned. I will advise you to try to avoid this by sticking something under the unit asap as these are small parts and there are room for them to drop down beside the inlet valves. No fun trying to catch them with a magnet afterwards...
Here these inlet valve actuator parts. Parts at right side faces towards inlet valve top, i.e. downwards
Update: If these parts fall out as shown here below a very small lock ring is missing ! Try to find a replacement, I damaged the parts during assembly as they fell out and got jammed !
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Now you have the unit placed on your work table.
Remove the sheet metal MA unit top cover using a T25 bit. Around 20 screws holds this cover. When the cover is removed, the arms with rollers between inlet cam and MA unit can be moved away and spring and piston can be removed.
Now the 'could-be-loose' hollow nut (or cylinder) is accessible. My number 4 could be turned using two fingers !
A 17mm hex top fits. Thread is M22x1 if anyone should consider reparing it.
I tigthened the remaining 3 nuts/cylinders using a calibrated torque wrench and going up in steps from 20 Nm to find the torque they were tigthened with. All were tight at 40 Nm, 2 out of 3 moved a bit at 45 Nm.
I then degreased the threaded parts on the defective unit, added some Loctite 648 (strong thread lock) and torqued it 40 Nm.
As I had the sheet metal cover of the unit I decided to fill the voids in the unit with engine oil in hope that it would make the bleeding of the unit quicker. I'm not sure it made a difference, but it can't hurt.
Put pistons and spring back in nut/cylinders, move the arms with rollers back in their place. Place the sheet metal cover and make sure the rocker arms are inside the guide arms on the cover. Mount the many T25 screws and tighten. I use a T-wrench singlehanded, that will be around 10 Nm.
Test if all 8 inlet valve actuators is safe, i.e the lockring works. Use a light pull in the piston with 2 fingers. I strongly suggest you find other actuators from a scrapped unit or find replacement lockrings, if your pistons falls out. I tried to secure mine using a pinch of grease and ended up damaging an actuator during assembly.
You are now ready to return to Ransomans guide and mount the unit. I will add one comment though: First time I mounted the unit, I just pushed it down and tightened the bolts. That means the inlet camshaft will we interacting on all 4 units during assembly, and that does not help you getting it in place.
I was told on the danish clubs forum, that there is an assembly tool with E-per no. 2000043500. Ididn't have to think long to invent something, that would help during the assembly process: Rollers pushed in, 4 short bolts jammed between roller frame/arm and the sheet metal cover pins stopping the roller units from going too far out. I used M8 bolts on the 2 cylinders where the cam was 'active' and M6 for the other 2. This made assembly a lot easier. The cam interaction caused the bolts to be released during assembly.
This shows the M6/M8 bolts in place and unit ready for mounting.
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I tightened the 9 pcs T45-bolt 25Nm.
I did not remove the vacuum pump, instead I removed the stud bolt using two countered nuts. It is then possible to lift the valve cover vertically up with the punp in place. I also left the turbo heat covers in place.
More pictures:
Unit disassembled.
From top: 4 pcs spring/pistons, the many T25 screws, the sheet metal cover facing inside up, MA unit body with the nut/cylinders facing out. Number 4 (right) nut/cylinder is removed and is placed in lower right corner of the photo. The 4 arms with rollers are rotated out of the way to the left.
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Looking down into cylinder 4 sparkplug tube. Inlet valve tops are in top of picture, cam is in lower part of the picture. The rightmost cam lobe is actuating unit 4 inlet valves.
![]()
Check out Ransoman's guide on removal of the unit, then I will take it from there.
I had valve actuator parts falling out of cylinder 4 unit as I lifted the MA unit off, just as Ransoman had warned. I will advise you to try to avoid this by sticking something under the unit asap as these are small parts and there are room for them to drop down beside the inlet valves. No fun trying to catch them with a magnet afterwards...
Here these inlet valve actuator parts. Parts at right side faces towards inlet valve top, i.e. downwards
Update: If these parts fall out as shown here below a very small lock ring is missing ! Try to find a replacement, I damaged the parts during assembly as they fell out and got jammed !
Now you have the unit placed on your work table.
Remove the sheet metal MA unit top cover using a T25 bit. Around 20 screws holds this cover. When the cover is removed, the arms with rollers between inlet cam and MA unit can be moved away and spring and piston can be removed.
Now the 'could-be-loose' hollow nut (or cylinder) is accessible. My number 4 could be turned using two fingers !
A 17mm hex top fits. Thread is M22x1 if anyone should consider reparing it.
I tigthened the remaining 3 nuts/cylinders using a calibrated torque wrench and going up in steps from 20 Nm to find the torque they were tigthened with. All were tight at 40 Nm, 2 out of 3 moved a bit at 45 Nm.
I then degreased the threaded parts on the defective unit, added some Loctite 648 (strong thread lock) and torqued it 40 Nm.
As I had the sheet metal cover of the unit I decided to fill the voids in the unit with engine oil in hope that it would make the bleeding of the unit quicker. I'm not sure it made a difference, but it can't hurt.
Put pistons and spring back in nut/cylinders, move the arms with rollers back in their place. Place the sheet metal cover and make sure the rocker arms are inside the guide arms on the cover. Mount the many T25 screws and tighten. I use a T-wrench singlehanded, that will be around 10 Nm.
Test if all 8 inlet valve actuators is safe, i.e the lockring works. Use a light pull in the piston with 2 fingers. I strongly suggest you find other actuators from a scrapped unit or find replacement lockrings, if your pistons falls out. I tried to secure mine using a pinch of grease and ended up damaging an actuator during assembly.
You are now ready to return to Ransomans guide and mount the unit. I will add one comment though: First time I mounted the unit, I just pushed it down and tightened the bolts. That means the inlet camshaft will we interacting on all 4 units during assembly, and that does not help you getting it in place.
I was told on the danish clubs forum, that there is an assembly tool with E-per no. 2000043500. Ididn't have to think long to invent something, that would help during the assembly process: Rollers pushed in, 4 short bolts jammed between roller frame/arm and the sheet metal cover pins stopping the roller units from going too far out. I used M8 bolts on the 2 cylinders where the cam was 'active' and M6 for the other 2. This made assembly a lot easier. The cam interaction caused the bolts to be released during assembly.
This shows the M6/M8 bolts in place and unit ready for mounting.
I tightened the 9 pcs T45-bolt 25Nm.
I did not remove the vacuum pump, instead I removed the stud bolt using two countered nuts. It is then possible to lift the valve cover vertically up with the punp in place. I also left the turbo heat covers in place.
More pictures:
Unit disassembled.
From top: 4 pcs spring/pistons, the many T25 screws, the sheet metal cover facing inside up, MA unit body with the nut/cylinders facing out. Number 4 (right) nut/cylinder is removed and is placed in lower right corner of the photo. The 4 arms with rollers are rotated out of the way to the left.
Looking down into cylinder 4 sparkplug tube. Inlet valve tops are in top of picture, cam is in lower part of the picture. The rightmost cam lobe is actuating unit 4 inlet valves.
I will link this in my original thread as this is great help.
