Need a little advice here:

Have a '92 400E w/102K miles. The timing chain was rattling at start-up, but as soon as oil pressure jumped to "3" it quieted down to normal. Ran fine...

I took it in and had them replace the timing chain, tensioner, upper rails, etc...
Took it home with a big $800 smile thinking I was good for another 100K.

Next morning, SAME NOISE! Tested the smog pump clutch (unplugged), not that... Same symptom, after the car sits a hour or so, start it and it sounds like a diesel (sorry "D" fans) for the first second or two until the oil pressure jumps to "3" then quiet...

Once started, it will start quiet for hours, but once left to sit for a few hours or over night, the noise returns at startup.

Took it back, and of course, THEY didn't hear a thing. They took the valve cover off to check things out and all appeared to be OK. Picked the car up (and it didn't make the noise, making me look a little sheepish), go home, let it sit and ...YEP same thing....

HELP
Tks
BOBB