Strange new noise when starting 94 SL2
 

Our 94 SL2 for a brief moment sounds like a diesel as the car starts.
I replaced the engine in 1999. It must have about 90k on it now. The odometer stopped working at 216k last year.Any clues as to what to look at?
Thanks, in advance.

Ray

I'd start with all of the pulleys. Remove all of your belts and start the car and see if you hear the noise. If not, add one at a time back on and see if the noise starts. Then you determine which is making the sound. If it does it with all the belts off, then it might be the timing chain. IDK, I'm not much of a mechanic. Just been wrenching on my own cars for over 40 years.