I've been waiting and watching to post this on SL for quite sometime now so here it goes:

I have an '05 Auto with Injen CAI, Strupp headers, a Tanabe axle back, and the NST pulley kit ... other than suspension mods thats it. Starting around 45,000 mi I started to get a stutter in my acceleration (read "engine stutter" for full story on that). While in iraq I had mechanic buddy take a look at it because i was getting some crazy answers. What he found was that my engine was firing on only three cylinders randomly ... he still doesnt know why ... and when it was doing that it was throwing fuel into the exhaust which ended up melting my cat, so he removed the cat and left it a straight pipe. Now, it runs perfectly smooth where it used to stutter, however I've noticed that prior to 4k I am seriously lagging in power once I hit 4k the car takes off. It honestly feels like turbo lag ... but way delayed. If anyone can give me any sort of diagnostic that would be great

 

Did he install some Vtekz in it?

 

no he didnt install anything just replaced the cat with piping

 

No CEL? Which cat was replaced?

Any ECU monkeying going on?

 

im not running any cats right now due to the headers ... so yes a CEL is being thrown cuz the O2 sensors are confused ... havent touched the ecu ... anyone think it could be the vvti

 

typically, random misfires mean either an ignition coil is bad or the ignition control module is bad. chevy's from the early 90's have this problem, especially the 3.1L and 3.4L. As for the lag, its probably your cat. The ecu scans the o2 22 mins after start up. if you get a CEL elimenator it should fix it.