i have a 92 hatch cx with a d15b. lately i have been noticing that on cold starts my car begins to pop. it is not very loud but the whole car shakes slightly when it pops and the rpm's drop around 500-1000. it is wierd because i am not throwing any codes. is this normal?

 

sounds like a backfire or a missfire

 

check your iacv abd also your tps sensor connections. It may also be your o2? check for ecu codes

 

i am not throwing any codes and i. also i have already checked and cleaned my iacv and still nothing. If it was a misfire i would throw a code right? but i am not throwing any codes.