i have a b18b1 and whenever i let the engine idle for about 10 minutes, tap the gas, blue smoke puffs out. i just installed a megan racing 4-1 header. still have stock cat but since i put the header on it sounds like a subaru wrx. i am thinking the cat is messed up. cylinder leakdown test checked out fine. i put 20psi each cylinder and had 10 or less leakage. im going to try to do temp readings on the cat tonight. any help or ideas is greatly appreciated. thanks!

 

You probably damaged the O2 sensor or the O2 sensor wiring during the header install. If this is completely new behavior since you installed the header, and nothing else has been changed since the header, why would you suspect that the cat is messed up?

 

i just put new ngk wires and plugs. new dizzy cap and rotor. and new fuel filter (it all needed to be done anyways). tonight or tomorrow i will be running the temp test on the cat and what readings the o2 sensor is giving also. i am suspecting the cat due to the wrx sound. plus once everything gets hot, it dont seem like much exhaust is coming out the muffler. im running a obx exhaust on it. i also just adjusted the valve lash this morning cause the motor has about 15k since the complete overhaul. the thig that still has me stumped is that it NEVER burned oil till the header install. if that cat is clogging up it could suck oil past the valve seals and guides for what i have read. mainly just trying to see if anyone has had this weird problem before and what their fix was. ive been researching for 2 days trying to figure it out.

 

you can hook up a vacuum gauge to see if there is a restriction in your exhaust and if you did have one you would have very pooor drivability.. also when doing a leakdown test you should be using way more than 20 psi

 

What psi would you suggest doing it? And cat was 260 inlet, 200 outlet.

 

260 what and 200 what? Teaspoons? Gallons? Donkeys?

 

i have a snap-on leakdown tester and use close to 100psi.. also u need to check to see where you leakage is coming from otherwise doing a leakdown test is pointless

 

degress. 260 degree inlet and 200 degree outlet on the cat. at idle and just letting it run for about 10 minutes. no drive time at all with those temps. and ill be sure to redo the leakdown test this weekend when i can get back to my garage.

 

Degrees F?