Greetings to everyone here,
My vehicle is a W176 2014 2.1 cdi.
fixed a DPF fault and an exhaust pressure sensor fault since I purchased it; still working through a few other difficulties.
I was a heavy-vehicle mechanic for a while, but I left that field years ago. Lately, I've been thinking that maybe a boost fault is to blame when the car goes into limp mode at higher speeds and boost levels, albeit it happens less frequently while idling. I have examined the vacuum lines and air intake lines for signs of wear, but they appear to be in good condition.
Last night, I conducted a smoke test. I started by checking the vacuum line that goes to the brake cylinder on the bulkhead (I forget its name), and it came back clear. Then, I moved the air intake unit to the area after the air filter to see if there was a problem. To my surprise, I discovered an oil leak that I had never noticed before. It was discovered that the leak was caused by loose screws on the rocker cover. After I snugged them all, I did a smoke test once more, and the leakage stopped. My question now is whether smoke should have been present there initially. I can't recall why smoke from the air intake pipe would wind up in the rocker cover; it's been so long since I played the game. After tightening the screws, I put the car through its paces on the road, but it still goes into limp mode when I apply too much boost pressure or rev too quickly.
Has anyone ever smoke-tested anything before, so I'm not sure if there are certain points to test or if I should use a variety of pipes. Would be eternally grateful for any assistance.