Today I jis purchased Motul Turbolight 4100 after a few mates recommended it, as soon as started my baby was the whole engine began to shudder, it settled down after reaching temp (which is at exactly half, same as previous oil) however when driving under 2.5 - 2K revs would still shudder, my presssure has dropped also to below 4, and wait for it, turbo doesnt boot in at all, jis feels gutless and runs ruff as rocks. What would be the best thing for me to do to fix this?
Thankyou.