<![CDATA[Need help interpreting VVT (Variable Valve Timing) live data - Unusual values?]]>I am currently diagnosing my engine's VVT system and I am struggling to interpret the live data stream I pulled from the ECM.

I’ve attached a screenshot of the current readings at idle (867 RPM). Could someone with experience please help me understand what these specific parameters represent and whether these values indicate a potential issue?

Thanks in advance for your help!
Screenshot 2026-06-18 160035.png

]]>https://forum.d5t5.com/topic/341/need-help-interpreting-vvt-variable-valve-timing-live-data-unusual-valuesRSS for NodeFri, 19 Jun 2026 15:04:02 GMTFri, 19 Jun 2026 09:11:47 GMT60<![CDATA[Reply to Need help interpreting VVT (Variable Valve Timing) live data - Unusual values? on Fri, 19 Jun 2026 13:42:57 GMT]]>@T5-T6-Schnappi Thanks for the advice. The error code I’m getting is P0420, related to the catalytic converter. My engine has recently undergone an overhaul, with the pistons replaced due to oil consumption. Since the rebuild, the engine doesn't behave like it used to— there’s a tingling sensation on the steering wheel, and it feels like I’m driving a diesel.

Besides the comfort issues, fuel consumption has increased to about 9.5L/100km (before the repair, I averaged 7.5L/100km). Now (20 000km after rebuild) I’m also getting errors related to the lambda sensors. I know that the mechanic unfortunately didn't assemble the engine according to the official Volvo procedure—they didn't use the required locking tools and just relied on timing marks. Therefore, I am certain the balance shafts are incorrectly installed, but I’m also worried about the timing and the VVT settings.

I also know that this car can be quite tolerant of certain issues... for instance, when I had a faulty PCV system, no error code appeared, even though the crankcase pressure was clearly compromised.

]]>https://forum.d5t5.com/post/1315https://forum.d5t5.com/post/1315Fri, 19 Jun 2026 13:42:57 GMT<![CDATA[Reply to Need help interpreting VVT (Variable Valve Timing) live data - Unusual values? on Fri, 19 Jun 2026 11:24:25 GMT]]>@DanForester If any off these values would be out of range you would immidiatly get a CEL, limp mode and one or more DTCs. You can also look the values up in VIDA. If you don't have VIDA, ask for a copy here.

]]>https://forum.d5t5.com/post/1313https://forum.d5t5.com/post/1313Fri, 19 Jun 2026 11:24:25 GMT