Hello Matthew just been looking back at the posts , I'm still not sure on the vaccum readings at idle , most modern engines with higher compression ratios and the volumetric efficiency they run most of em can pull 20 inches Hg of vac .
I test vaccum in engines quite a lot and I normally see on good engines 20 or 21 inches Hg .
Yes the emissions test looks good , but sat still whilst on test at a certain revs is not the whole picture of the engines map , when ecm sees road speed things change ..load changes , cam timing had to be ruled out .... I know this is a bit of a task stripping it down .....but what's the option .....buy some more parts on a whim and hope they fix it ( like I see near enough everyday in the workshop )
My next tests as I have said before would be cam timing checks with the correct tools , if all other possibilities of inlet manifold leaks have been ruled out its the next step , very often with diagnosis it's a case of rule it out then move to next step .
If this shows to be good then my next step would be pull all the injectors out and flow and pattern test them .
On vcds on the camshaft position actual and camshaft postion phase position , actuator duty and so on data block page , could you screen shot it , take a picture or whatever and post it up , one at idle one at say 3000 Rpms .
Another possibility.....could your next door neighbour be sneaking out in the night and syphoning a couple of gallons out of your tank for his scooter .......
Last edited by Mechcanico Lee; 22nd January 2017 at 12:18 PM.
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