Both do the same thing. The yellow one is just see-through so you can tell if it's clogged. The metal one would look similar if you cut it open.
I wonder if they failed to adequately tighten your distributor down after they did the timing. I would check the timing to start, since that's what it was before.
A word of caution: If the timing is off again, you could have a bearing in the distributor failing. I had this happen on my 83 2.3 Ranger and it ended up being the death of it. My distributor spun and the engine ran rough then died. I had just had the engine out to change gaskets and paint it, so I figured I had not tightened the hold-down bolt enough. So I redid the timing on the side of the road and took caution to make sure I tightened it well.
I didn't get another mile before it spun again, this time with a violent backfire. This time I could tell the distributor was shot so I got another at a parts store. When I started it up, it ran fine for a few minutes, but then made a terrible racket. After pulling the head, I found a piece of metal in the number 3 cylinder and it beat the hell out of the piston and marred the bore. My best guess is that the backfire had knocked something loose and it was sucked into the motor after I started it back up.
So inspect the distributor. Make sure there's no chirping sounds coming from it indicating bad bearings. It's not common, but it really bit me in the rear end.