Hey everybody. I got my 94 FD a few months ago and added a DP and exhaust. I have upgraded to silicon hoses, gauges, and radiator as well, but my question is...when i'm idling or not on the gas...I hear a faint popping sound coming from my exhaust. It is a popping sound that pops like 3 times in 2 seconds real faintly. Is this normal with dp/exhaust or is something wrong? Help me out...

 

bump

 

Like a mild backfire?

 

very mild backfire. when i start the car in the morning...it revs to 3k for about 7 seconds and then lets out 3-5 louder backfires before idling normal...

 

Completely normal. Rotaries backfire alot. Especially upon a cold start when you start opening up the exhaust. I wouldn't let it rev if it was my car but anyways...no worries 100% normal

 

Mine does it too when its cold, just a normal thing that the Rotary does like everyone else says. I have DP and cat back. After its all nice and warm it stops backfiring almost completely.

 

so even after the car is warmed up, it's normal for it to backfire mildly when i'm not on the gas? in the morning on a cold start i can't help but to let it rev up. i'm not on the gas or anything...

 

oh ok...i was concerned b/c i was told that the backfiring puts a lot of stress on the seals and i just got a new motor installed and don't want anything else going wrong.

 

any backfiring is normal. To make it stop revving upon cold start, start it in gear or tap the gas upon starting it.

 

i dont think its normal to back fire sitting at idle...

 

It's not really a backfire per se, but just a rich misfire. Rotaries are prone to "spitting", and sometimes new plugs can help out quite a bit.

If you have a small exhaust leak somewhere, you will also get some weird noises from the leak area - hard to describe the sound.

Regardless, I don't see anything out of the ordinary. You're OK.

Dale

 

Mine idles with a soft paaaapapapaaaaaapaaaaa kind of sound until it's really warmed up. As far as I've heard, it's all normal.

Exhaust leaks tend to give the engine a real raspy sound or lawnmower-chainsaw sound.

Dave