I have a weak idle and occasional misfire code (multi). The initial fault was the intake manifold gasket. I replaced it and this seemed to fix the problem........ but only for 3 days. I therefore suspect another leak but there is nothing obvious. - I've tried pressure testing by plugging the main ...

I have a T6 and when connecting to EOBDII it shows that even when the gas peddle is planted to the floor, the throttle position is max 85% .

Does anyone else see this ?

Hi , re the vacuum hoses , I only have the break servo hose and the boost control hoses. They all seem good. I also have various potential points for leakage as this car is converted to run on lpg but all these are also good ( no bubbles on the pressure test.)
With regard to fuel trim, I don't ...

Hi , I'm not familiar with the T5 but have done my t6. It's quite awkward to say the least. The actual one way valve (allows induction vacuum to pull in blow by gasses when no boost and closes when boost pressure is higher than blow-by, the blow by is then drawn into the induction tract of the right ...

Hi , re the vacuum hoses , I only have the break servo hose and the boost control hoses. They all seem good. I also have various potential points for leakage as this car is converted to run on lpg but all these are also good ( no bubbles on the pressure test.)
With regard to fuel trim, I don't ...

Hi , I think it's either a bosch or VDO. As you mentioned , I don't think the xc90 ever suffered from this issue.
One interesting thing is that on the Eobd the throttle never opens more than 85%. I think volvo may have reprogrammed to give the gearbox more of a chance. (After a new box was fitted ...

Hi All,

A slightly embarrassing discovery/solution.
Having checked every fuse an relay taken most of the removable dashboard panels off , pulled out the DIM, stripped the CEM down to PCB level, dismantled, tested and reassembled the ignition switch. Checked wiring diagrams from all angles ...

Hi , I guess and hope you have sorted this now.
From memory, you don't need to disconnect the turbo oil feed but you do need disconnect the coolant line from the left ( as you look at the front ) of the head. A banjo with copper washers. Also similar at the end of the head on the right hand side ...

Hi all. Update ,
I'm assuming that the battery is ok as there are no issues with starting.
I haven't replaced the ignition switch but I have tested it. It seems to be fine. I removed the white cover and checked each contact by pressing the "cam followers" no signs of wear etc.

Any other thoughts ...

Hi , thanks for the guidance , seems to make good sense. I will go digging an report back