Chirping 2014 Chevy Cruze

I have a 2014 Chevrolet Cruze LT 1.4L Turbo. Rebuilt title with rear damage
and undercarriage damage according to the title. When I first purchased the
car in 2017, a month into having it it began to make a chirping noise. I told
the dealership and immediately got it fixed, the mechanic said it was not the
timing belt, as another mechanic had told me it was. I didn't ask any further
questions due to lack of knowledge. The car did not make any noise for
about two years. Performance wise, it would sometimes feel like it hesitated
when I would accelerate, but I just figured it was because of the small
engine. Recently, about a month ago the car started making the same noise,
and now the engine jitters and is definitely not working at its full potential. I
had one mechanic tell me it was the timing belt and I immediately got that
changed. The problem continued. I had another mechanic run his computer
and tell me I had to replace mt MAP sensor and both the upstream and
downstream oxygen sensors. I did that yesterday and the car is still making
the same noise, nothing has changed. Please if anyone might know what
could be the problem reply to this. I have already spent more money than I
should have had to and my car still isn't fixed. Thank you all for reading.