So i bought a set of lightweight pulleys for my b5 s4, and as i'm installing the driveshaft pulley, it moved. Is this bad? Can I fix it? If so, how?
Thanks!

 

are you talking about the crank pulley? the pulley's involved in the lightweight pulley kit have nothing to do with timing. moving them shouldnt be an issue.

do you have the ecs pulley kit?

 

Yes, the ecs lightweight pulley kit, when loosening one of the eight bolts the pulley turned, I put it back together, and its been running a little rough, and threw a misfire code for every cylinder. Threw codes for fuel trim as well. What should I do?

 

I did the apr bi pipe at the same time, my tech says it might be boost leak, advice?

 

damn!

first and foremost definitely check your hoses for leaks just to make sure. also check your coil packs cause they create misfires when they go bad. i have no idea why turning one of those pulleys would do this.

did you do your timing belt as well?

 

No didn't touch timing belt. Would a boost leak at the tb do it?

 

this would have to be a pretty big boost leak to do this.
did you remove the tb during the bi-pipe install? if so did you replace the tb gasket?

did you do anything else to the car while installing the pulleys and pipe?

 

Yes to tb removal, no to gasket, I'm assuming I'l be doing that today to see if that does it. Apr snub mount same time, that's it.

 

the gaskets are only one time use. did you forget to plug something in? crank angle sensor?