NEED SMOG HELP!!!!!!!!!!!!!

[naughtydawg]

hi, im new to this forum but not new to s13's. im stuck i dont know how to get my car better emissions and better mpg. i have a 90 s13 with a ka24de that i swapped into it. i get 20mpg every day driving mostly highway. the car runs great though, no sputter, it never dies and has lots of power. my spark plug wires test good, i have new plugs, new cap and rotor, my timming is where its suppose to be, new injectors, new maff, oil change, i sea foamed the car, i put guarantee to pass, my fuel pressure is at 40psi while running, my egr works(the test guy and i disconnected it at the station and the nox shot up an extra 1400) and i have a brand new cat but my emission readings are

hc co nox
max/measured max/measured max/measured
15mph 85/124 0.54/0.64 565/1802
25mph 67/32 0.45/0.15 522/811


any help would be much appreciated thank you.

[compactfean]

Even though your egr is working I would clean the ports in the intake manifold. Also check your air injection system (very commom to have problems) do you have a new couldnt temp sensor?

[naughtydawg]

cool thanks ill look at those... even if the temp sensor is reading the correct temperature could it still be bad? i have a new temp sensor on my sr i think ill swap them tomorrow... any other ideas by anyone?... could a pcv valve be doing this at all? or??

[compactfean]

Pcv valve is just to keep your crankcase from sludging up. As far as the cts, there us one for the gauge (single prong) and one for the ecu to adjust fuel according to temperature so the answer to that is yes. Also do you have an aftermarket thermostat? And also fuel pressure seems a tad high. Should be at 43 @ idle with vacuum line OFF.

[biggie]

^And 33-34psi at idle with Vaccum on.

[naughtydawg]

that might be the problem then... the fpr.... i thought it could of been it but when i looked online and saw different fuel pressure readings and i kinda just picked the one i had to be normal lol... i have an ajustable fpr on my sr so ill switch that too.. yeah i changed my thermo after i had the test and then tested it again with no change...i knew the main function about the pcv but i read something about it helping emissions in a way but i didnt know by how much. thanks for the specs and the help ill let you know if it works.

[compactfean]

The way it helps emissions is by sucking the crank case gases back into the engine to be reburned instead of letting it escape into the atmosphere. (blowby gases is raw hc.)

[AHall]

Your NOx still seams high to me, especially after all the work you have done. For a properly functioning EGR system, your NOx should be way down. Gas mileage is also low. I get around 30+ for just highway driving, but I drive conservatively. The new CAT may be covering up a lot of problems. High HC is unburned fuel but you have done what appears to be a complete tune up, including new mass air flow sensor. Are all your parts new? Also have you ever passed emissions before with this car? Search my post on emissions. I have battled emissions for years.

[naughtydawg]

ok well i have a new coolant temp sensor and new sparks plugs (just cause) i tried the denatured alcohol and i passesd co and hc but nox was still too high. the alcohol made my car have less power. i cleaned out my egr system and everything seams like its working properly.