89bulletlx

Ok i started my car up last night and every time i rev it it backfire .Has any one had this issue 89 mustang 302

91hatchgt

It backfires? Or the exhaust pops as the idle unwinds?

89bulletlx

it backfires when reving up not when it drops

91hatchgt

Wierd.. What are your mods?

89bulletlx

5.0 Edelbrock Performer 5.0 EFI Intake Msd 6AL MSD blaster coil March Performance under drive pullys a/c ELIMINATOR smog ELIMINATOR cam bbk cold air bbk70mm THROTTLE BODY 73mm mass air ford raceing headers and H pipe 40 flowmasters T 5 TREMEC 373 9' ford rear end

89bulletlx

could bad spark do it

aode08

clean your MAF with electrical contact cleaner.

Then check your spark plugs.