I need your opinion on lightened pullies/flywheels

Hello! I have a CEL that I was told was related to my lightened flywheel and crank pulley. My co-worker (motor-head) said that as every explosion in the combustion chamber not only pushes down on the piston, it sends a sharp vibration through the piston, rod, and into the crankshaft. The crank has a dampener on one end and a heavy flywheel on the other. The shocks and vibrations produced by the explosions would get absorbed into these heavy components causing little to no wear on the crankshaft/block/rods/pistons/etc.

Okay, so what if we're using this theory. The vibrations and shock that goes through the motor when a lightened flywheel and/or pulley is installed would cause greater wear in the motor and eventually cause enough wear to break down the motor in the long run. Correct? The lightened pulley and/or flywheel won't absorb the vibrations as well causing unnecessary wear to the motor.

I've had a lightened pulley installed on my old MY00 RS, and at idle, the crank pulley doesn't spin evenly... but as the motor is revved/driving, it spins easily, evenly, and has better response. I've even felt the motor feel a lot more smooth as the RPMs raises. Our motors have a 1-3-2-4 firing order: basically two combustions on one side of the motor and then two more combustions on the other side. I'd like to get your opinions on this issue.

 

That's an interesting theory. So in theory, if you lightened both the "dampener" as well as the pulley, it would balance out? I doubt that that is why the CEL is on however, my guess is that the engine just senses the less resistance from the lighter pulley and is saying, "Hey you modder! Quit foolin' around with me!"


Or something to that effect.

 

Noah, that's what I'm talking about!

Todd, I have not looked at the CEL(s) yet. I'll see if I can soon. Always gots things to do.

 

The combination of a lightened flywheel and lighter/underdriven pulley seems to cause misfire CELs, based on a few nasioc searches. I saw several people recommending that one mod or the other probably won't cause problems, but the combo does.

Here's just one of many example threads I found that seem pertinent:

http://forums.nasioc.com/forums/showthread.php?s=&threadid=452243

 

Thanks for the link, Zola. It seems like the CEL only comes on under light load or when the car is just starting to move. That may explain why at idle, the crank pulley looks like it's wobbling but as RPMs raise, the crank pulley smoothes out. Going too light for the pullies/flywheel may allow a bit more shock to the system. If I remember correctly, that's when my CEL came on after my battery was reset by Todd's shop. I may have to take off my Perrin pulley and replace it with the stock one in the Spring to see if the CEL goes away.

 

You know, you can rent an OBDII code reader from Checker? It's a fully refundable $200 rental fee that you could put on a credit card. You can check and clear the codes. Otherwise, disconnect the negative cable from your battery for 5 mins and it will reset your computer.

You might already know this though...

If so: [xx(]

 

Even easier is going to Autozone...they send someone out to the parking lot to scan it for you right then and there. No refundable fees or anything, just free.

 

Just done that. I have 2 codes; 4 total:

(2)P1139 -Front oxygen (A/F) sensor #1 heater circuit perfomance/range problem
(2)P1130 -Front oxygen sensor circuit malfunction (open circuit)


I might need a front O2 sensor. ! The car runs fine though.:???: It may be some wires that weren't connected when the car got reflashed. The previous owner said that the car never had any CELs when it was using the UTEC/Link.

I guess it's not related to the lightened pulley/flywheel?

 

Thanks, Russ. I have an ECUTek reflash to the WRX ECU for engine management. I will check out my connections, but it's gotta be decent outside before I go. My car runs fine even with those CELs, so it's wierd that I have CELs on the front O2 sensor.

I've owned a MY00 RS that had it's front O2 sensor go out (warranty recall). It would shake and gag under light throttle, and it would only drive better when the throttle is fully open. It wasn't very safe in public roads. }