After installing aftermarket clutch and light weight flywheel, i noticed the RPM dropped during idle. It's about 500-400 now. When it gets to about 400, the car shakes as if its about to stall. But then, it bumps back to about 500 and repeat..
i don't think this is caused by light weight flywheel.. Is it either bad MAF sensor or fuel pump?
I cleaned the MAF sensor, and unplugged the battery overnight but didn't help. No unusual lights came up on the dash..

 

Might be an intake leak...

 

I have the same issue i checked the whole intake and cleaned the Maf with cleaner for it and the same issue, i just recently put a flywheel and clutch in, lightweight 12.8 lbs and stage 3, the rough idle was there before but now its WAY worse, i have to trn the AC on to get it to calm it down, also i have lost about 60 miles per tank...

 

exactly same here..except for the MPG part lol
Mine is still not fixed..

 

Check

Your

timing

 

ignition timing?

 

Gonna have a guy look at it with a snap-on box and see what comes up, if its a timing issue it should come. thanks for the help.