Volvo V70 VVT-solenoid trace

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volrem
TwoWaves
TwoWaves
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Location: Estonia

Re: Volvo V70 VVT-solenoid trace

Post by volrem »

Do you still get fault code ECM-6400 Signal too low ?

There is no information in technical pubication how this condition is checked (voltage or current). But it is electrical for sure.

If there is position problem then code ECM-640A or ECM-640F is stored.


Your current and voltage trace is different indeed. However I can't say that it's the cause for your problem.

Is this code stored often?

kukushka
OneWave
OneWave
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Joined: Sat Feb 18, 2017 6:30 am

Re: Volvo V70 VVT-solenoid trace

Post by kukushka »

Hello,

The code is now ECM-640A. The non-oem valve does not adjust the cam properly, so the difference in actual and measured advance of the cam triggers this?

volrem
TwoWaves
TwoWaves
Posts: 243
Joined: Fri Jan 03, 2014 3:43 pm
Location: Estonia

Re: Volvo V70 VVT-solenoid trace

Post by volrem »

ECM-640A is stored if cam position deviates too much (over 10 degrees for longer than 15 seconds).

Put Pico aside for a moment and use your scan tool.

There are two data PID-s to check. Camshaft actual and camshaft desired value.

At idle check that these mach. And then do this when driving.

When values at ide deviate too much (more than 5 degrees, but should be close to 0) then first thing to check is cam physical timing. Belt may be jumped or VVT unit incorrectly installed on camshaft.

kukushka
OneWave
OneWave
Posts: 34
Joined: Sat Feb 18, 2017 6:30 am

Re: Volvo V70 VVT-solenoid trace

Post by kukushka »

volrem wrote:ECM-640A is stored if cam position deviates too much (over 10 degrees for longer than 15 seconds).

Put Pico aside for a moment and use your scan tool.

There are two data PID-s to check. Camshaft actual and camshaft desired value.

At idle check that these mach. And then do this when driving.

When values at ide deviate too much (more than 5 degrees, but should be close to 0) then first thing to check is cam physical timing. Belt may be jumped or VVT unit incorrectly installed on camshaft.
The actual timing won't change. It stays under 1 CA, even when the desired is 10 CA.

Check the timing first, and if that is OK, then the VVT unit is broken?

volrem
TwoWaves
TwoWaves
Posts: 243
Joined: Fri Jan 03, 2014 3:43 pm
Location: Estonia

Re: Volvo V70 VVT-solenoid trace

Post by volrem »

If it shows actual to be around 0 degrees then timing should be ok. I don't remember exactly. To check you have to lock crank and cams.

If you have PWM tool to control VVT solenoid then use it. And if you don't have then get one or you can try to apply 12 directly. Engine running of course.

There could also be oil pressure problem.

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