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Discussion Starter #1
I hope that someone can help me with this.
Tried to remove vanos unit because I'm failing bank 1 vanos test.
Ran into a problem rightaway...cannot reach vanos assembly position hmmm
Solenoids and CPS are fine because I swapped banks.
Is it possible that one piston on bank 1 is stuck?
 

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How are you trying to get the cams in initial position? Easiest way is not the TIS way, but rather just to remove the solenoids. Then go through the regular process: turn engine to TDC overlap and lock crank, loosen the six visible bolts on each cam, unlock crank and turn engine to TDC firing position, loosen the six visible bolts on each cam, then use a machined 27mm wrench to move the cams into initial position and lock them in place. Then you are ready to unbolt and remove the vanos.

--Peter
 

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That screen shot of the first DIS assembly position screen shows strange cam timings on both banks. For an engine up to temp and idling normally, the intake cams should be around 54-56 deg and the exhaust cams 3-5 deg.

Was the engine up to temp when you did this?

Was this right after an attempt to to get to the assembly position?

Are you getting to the second screen where the values all go to 59-65 deg and the engine stops?

And the first thing to do if you are failing VANOS tests is do the solenoid board mtce before getting into the VANOS system. Have you done this?
 

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No fault codes?
 

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Discussion Starter #5
That screen shot of the first DIS assembly position screen shows strange cam timings on both banks. For an engine up to temp and idling normally, the intake cams should be around 54-56 deg and the exhaust cams 3-5 deg.

Was the engine up to temp when you did this?

Was this right after an attempt to to get to the assembly position?

Are you getting to the second screen where the values all go to 59-65 deg and the engine stops?

And the first thing to do if you are failing VANOS tests is do the solenoid board mtce before getting into the VANOS system. Have you done this?

Solenoids were cleaned and o-rings replaced. Bank 2 passes normally bank 1 fails even if i swap boards and CPS.
Engine was not warm when I tried to put VANOS in assembly position - DIS allows this unlike VANOS test.
I will try it again with engine up to temp. If it fails I'll have to open everything up and do it manually.

No fault codes only symptom is low-end power.
 

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OK, I see why you are going after the VANOS mechanism now.

The first screen below shows the cam timing at hot idle before DIS moves the cams to assembly position. The DME is calling for 55 deg intake and 4 deg exhaust under hot idle conditions so it's pretty close.

The second screen shows the timing after the cams have been moved to assembly position.

What I don't get are the bank 2 readings you show above in the LH screen, even though B2 passed the VANOS test. It's like they have already gone to the assembly position. I would expect the engine to be running very rough with those B2 readings at idle.

DSC01746.JPG

DSC01747.JPG
 

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Discussion Starter #7
Ok so I just did both VANOS tests and assembly position again with car up to temp. Assembly was successful, bank 2 passes and bank 1 fails.
It appears that I really have timing issue on bank 1.

When VANOS test was doing its thing on bank 1 chain was rattling very loud.
Tensioner was replaced 500 miles ago.

I think it is time to check timing :Thumbdown:
 

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That's useful. One of the problems with the DIS test is when it fails like your B1, it just stops at the point it failed and doesn't complete the test. But your going to assembly position shows how to get the missing exhaust retard for B1. Just use DIS to go to the assembly position. It shows your exhaust retard is 69.3 degrees. (Assembly position is the same as fully retarded.)

Your B1 VANOS is failing the test by maybe 3 degrees. An exhaust advance of 1 deg would have passed and and exhaust retard of 66 deg would have passed. So I wouldn't expect any obvious difference in performance when you do the timing.
 
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