How to find proper frequency peaks within a frequency spectrum?

Hello there,

I am trying to detect any mechanical issues these require maintenance by observing the feature's frequency spectrums created via data taken from accelerometer calculations which are made axial and radial (saved as .mat). I have to measure peak frequencies properly by using the code given by my instructor -he also insisted that I am obliged to use the code as it is- in order to get an idea about the condition of the system but I can't make programatical data tips that automatically detects peak frequencies in a reasonable threshold and margin. How can I get those data tips? My code is shown below, thank you for your time already.

clc
clear
load  BR.mat %%%data file
x=BR; %%%%%%Data file name
sp=fft(x);
nn=length(x);
sp(1:2)=zeros(size(1:2));
sp(nn-1:nn)=zeros(size(1:2));
x=real(ifft(sp));
fss=5000;
T=1/fss;
upfreq=fss/2;
p1=length(x);
z=(2/p1)*abs(fft(x));
z=z(1:p1/2-1);
z(1,1)=0.5*z(1,1);
nff=length(z);
nf1=round(2*nff*upfreq/fss);
z=z(1:nf1);
freqspec=plot((0:nf1-1).*(fss/p1),abs(z)),

freqspec = 
  Line with properties:

              Color: [0 0.4470 0.7410]
          LineStyle: '-'
          LineWidth: 0.5000
             Marker: 'none'
         MarkerSize: 6
    MarkerFaceColor: 'none'
              XData: [0 0.1163 0.2325 0.3488 0.4650 0.5813 0.6975 0.8138 0.9301 1.0463 1.1626 1.2788 1.3951 1.5113 1.6276 1.7439 1.8601 1.9764 2.0926 2.2089 2.3251 2.4414 2.5577 2.6739 2.7902 2.9064 3.0227 3.1390 3.2552 3.3715 3.4877 3.6040 3.7202 … ]
              YData: [0 1.4019e-18 0.0011 5.5658e-04 3.8345e-04 4.5997e-04 0.0019 0.0036 0.0020 9.3827e-04 3.8793e-04 0.0013 0.0024 0.0032 0.0012 6.2368e-04 0.0020 9.6836e-04 7.2553e-04 4.0302e-04 8.8694e-04 0.0016 0.0011 0.0030 4.2645e-04 5.2585e-04 … ]

  Show all properties

set(gca,'FontSize',10), xlabel('Frequency (Hz)'),ylabel('Amplitude')
axis([0 2500 0 0.05])
zoom on

[Mathieu NOE]

hello

look for findpeaks

you can also use text to create annotations inside the figure, once you know the x, y coordnates of the selected peaks