cars fast for a week then slow again

[byebyev8]

I've noticed that sometimes my car will be fast then one day its just slow for no reason at all
I can't figure out what the problem is either. like it'll be quick for a week then a few days later its back to slow again :thumbdown

 

[GalantGst]

the weather has alot to do with it

the colder it is the denser ur air will be meaning more power


whats teh weather like where ur at?

check for boost leaks, check for timing retard and knock with a datalogger.

 

[Tallen]

Check for leaky capacitors in the ECU.