schickdog Posted July 23, 2008 Share Posted July 23, 2008 Well, i fixed my starting issues, now on to how-well-she-runs. Actually, she runs like a top, the a/c blows icecubes, and gets 22 mpg city. take that. The problem is she won't pass inspection. Take a stab at this one. The truck has too high hydrocarbons at idle. O2, Co2, and CO are good, and hC' are fine at 2500rpm, but again, at idle is ~330. All vacuum lines are accounted for. I ran Seafoam 1 month? ago. SHe has new NGK plugs, wires, cap, rotor, PCV valve, air filter, and the EGR valve and the AIC valve are working fine. So i am assuming that she's running too rich. any thoughts, and if so, how do you lean it out? Link to comment Share on other sites More sharing options...
mws Posted July 23, 2008 Share Posted July 23, 2008 A lot of the TBI'd pathies have this problem. Mine does. I sneak it through by turning the idle speed up a bit. Just 50 rpm above the recommended idle speed does it for me! I use a smog tech I know, and have him hook it up and I just turn the idle speed up in tiny increments until the HC reading plummets - just a few rpm makes a huge difference. Haven't figured out why yet.... Link to comment Share on other sites More sharing options...
Precise1 Posted July 23, 2008 Share Posted July 23, 2008 Yes, exactly as Martin says, my old D720 needed the same treatment. As a matter of fact, it was the smog guy who showed me the tweek... Better compression/less blowby/slightly different timing?? It does help... Don't bother sneaking, run it at the highest rpm allowable. Also, a fresh oil change can tip the emmisions a few percent in your favor. I generally time my tune ups every 2 years. B Link to comment Share on other sites More sharing options...
94extreme Posted July 23, 2008 Share Posted July 23, 2008 idle at 330rpm's is way too low.. it should be double that or so. Link to comment Share on other sites More sharing options...
schickdog Posted July 23, 2008 Author Share Posted July 23, 2008 (edited) oops. forgot, 88 v6 3.0. and the hydrocarbons were 330ppm @ ~850rpm, not 330rpm. it's an "electo-ignition". is the idle adjust screw the big one behind the throttle linkage? and tighten to increase? been a while since i jacked w idle. also the oil is fresh, maybe 150 miles on it, 10/30. 93 octane gas, otherwise it knocks a lil. and just like every other, it has the exhaust-manifold tick. and thanks for the replies. Edited July 23, 2008 by schickdog Link to comment Share on other sites More sharing options...
Alkorahil Posted July 24, 2008 Share Posted July 24, 2008 idle at 330rpm's is way too low.. it should be double that or so. Yeah, i think its 750 rpm. Link to comment Share on other sites More sharing options...
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