[cheesefries]

My car was running perfect untill a week ago. When the car holds full boost (12psi) it will make a VERY loud bang sound comming from the exhuast and the whole car would hesitate. The nexy day I changed my spark plugs and the problem went away 100%. Well a couple days later it started doing it again. Now it rarely makes the loud bang sound but the whole car hesitates. My LINK ECU is saying there is 0 knock. Its a 1990 FM2. Any suggestions?

 

[slevin]

i don't know how relevant this is, but my car started to do that once.... after i upped boost and upgraded to bigger injectors.... i found the problem very quickly when i popped the hood while running. which was an injector o-ring that busted and was spewing fuel down the engine block and toward the hot exhaust which ignited it.

 

[DRFT MX5]

I'd suggest changing your plug wires, they are known to go bad very easy on our cars... its a relatively cheap option... thats where I'd try.