[quote="Lake_v2"]Crap...
High nox, passed 2 yrs ago when not on rollers, this time failed nox...
Only changes were fuel tank(which passed lol), hei dist, cold air intake
shop said possibly egr or pcv, currently egr isnt connected(wasnt last time), any ideas.
Im going to make an egr tube, but any other ideas before I take it back?
Fyi, 4.2 with 4.0 head, howell injection, hei, and new cat currently[/quote]
Well it passed with flying colors after hooking up egr, Becca had taken it there since i was working.
On way back from smog it ran outta gas and she coasted into gas station..
It wouldnt start after that, i bailed outta work to go get her and jeep, barely got jeep started, wouldnt hardly run at idle.
Started troubleshooting on the fuel side of engine, all lines were ok, fuel psi was good, changed fuel pump anyways because i had spare, still ran crappy, ran it out of a gas can no change.
Next i dug into the ignition and electrical, checked dist, coil, wires all ok.
Check sensors, codes, and timing all ok
At my wits end i took a guess and changed plugs and throttl sensor, no change.
Figuring that it cant be random and only change was adding an exhaust pot to egr, i pulled egr valve, found a tiny chunk of carbon holding valve open.
Cleaned valve reinstalled runs fine...
Maybe i should unhook it till next smog again lol