Safe to disconnect VVT while running the engine?

algopyguy · Post by **algopyguy** » 06 Nov 2020, 07:25

2002 s60 NA engine.. Just rather ask than try it and bend some valves...

Ty

Post by **abscate** » 06 Nov 2020, 09:16

Its fine. It is bad practice to disconnect electronic stuff, especially logic driven stuff, while it is powered up, but mechanically it can't hurt the engine.

The total cam flank range on the solenoid is only about 3 teeth on the sprocket at most.

Speculation - isnt the 2002 NA engine intake only VVT? Can the intake valves ever hit the pistons or is it only the exhaust valves?

algopyguy · Post by **algopyguy** » 06 Nov 2020, 15:59

VVT is on intake only on my NA engine.. I've got a rough idle /hunting and trying to ftrach down the cause.. A bad VVT shouldn't cause bad idle swould it? Ive taken it off and cleaned it, wasn't clogged..

Post by **jimmy57** » 06 Nov 2020, 20:50

I have not seen a Volvo CVVT that didn't set a code for cam control before it caused it to run or idle poorly. If the ETM goes wonky then ECM will randomly cancel injection on cylinders to keep idle speed down. No high idle and uncontrolled acceleration allegations that way. The randon cylinder cancel makes it idle bad.