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:bulb:Hey. Im new to the forum (post wise) ive read a lot of stuff on here over the last year, never had to post until now . So hello, Anyways. i have an issue with my 78 280z l28 (cold air intake, 2.25 exhaust glasspack muffler) 5 speed (straight gears). It is an arizona car and i need to pass emissions here so i can get my plates and registration. I can get the car to run great under a load and WOT with no miss or studdering. but my issue is idle. It has a rough idle. clearly a miss and rich exhaust. Ive taken it to emissions twice. The first time i took it was bone stock. no cold air intake, no exhaust. nothing done to it. and it passed everything within spec at the load speeds. BUT didnt pass at idle. it failed only with high hydrocarbons. pass is around 250 and it was putting out 890. so did a full tune up. plugs 45 degree gap, wires, cap, roter, cold air intake because my boots were broken and leaking air after the AFM. and 2.25 inch exhaust same cat (exhaust guy said it was still good) and same muffler (glasspack). did some tinkering with timing (which i cant get the white mark on the pulley to show up on the scale on the block so i assume the timing chain jumped, stretched, or someone did something wrong in a repair) and replaced one of the coolent temp sensor connectors (one closer to driver side) because it was totally destroyed. also tinkered with that big screw that is on the throttle body that lowers or raises the idle (also seams to make it idle smoother the higher the idle is, more rough the lower the idle is, its at about 1200rpms right now for the smoothest idle.. still has a miss and rich exhaust) i took it back to test again and it failed WORSE. passed everything under a load just like last time, but at idle instead of it failing at 890 PPM's HC it failed at 1300 PPM's. Please help me with any suggestons. i dont have a lot of tools or work space, and not a lot of money to take it to a mechanic.. if there is something i did wrong, or something i missed that is easy to check or needs a cheap tool to fix, adjust, or anything please let me know. I have to get this thing passed by the 16th or i cant drive it! and its my only vehicle.. Thanks in advance!!!!