JSAautomotive

Hello all,

Hopefully somebody can help me with this one. I own an automotive repair shop in L.A. California where we have a loaded mode (dyno) smog check. I've had a few cars that have come in here that were fairly modified that have passed the smog test on OBDII systems. The current pain is a 99' Vette with an A&A prepared LS1 and procharger. The car runs great and passes the tailpipe emissions if held in the right MPH/RPM band, but since California required that the car have all of it's emissions flags (also known as Diagnostic monitors) set, I cannot get this thing to pass. I've turned on all the logics for code loading and it will not perform the catalyst efficiency and O2 heater tests. These are the last two tests it must run in order to set all the flags so I can smog the car. Usually all it takes is a few drive cycles to get all the monitors to run, but it won't on this thing for some reason. I've also run the official "drive cycle" too to no avail. The car has it's cats, AIR system, O2's all in place. I've been fighting this one for around 2 weeks now.

Thanks in advance everybody!

John
John Stevenson Automotive
10158 Canoga Ave.
Chatsworth, Ca 91311
(818) 772-1737

ss rally red

iTrader: (8)

Yeah it sounds like you have covered all the bases, Georgia's emissions program is based on Cal. setup, I have done over 30K ET's in Ga. since 98. In our OBDII testing we dont have any visual inspection and 96-2000 cars/light trucks can have 2 "not ready's" and still pass, 01 and ups can only have 1 not ready and pass, If you have followed GM's drive cylcle to a T and still have not set all readiness monitors I would like to see how this is resolved, please update.

wrencher

iTrader: (2)

Someone has likely tuned the car with LS1 EDIT.
They turn the codes off for the rear O2's & the heaters so it will not turn on the ses light.
This in turn causes the PCM to not run & pass the readiness test for the affected system.
Your gonna need to get some info on the PCM if it was tuned (procharger?=likely)
Like who tuned & what was done.
You prolly gonna need to get the PCM re-done.

ss rally red

iTrader: (8)

This is possible but as I understand it the monitors can be set set to permanent ready but malfuntions will not be reported i.e, no P0300 random misfire for larger cams, is this possibly the case?

WS6FirebirdTA00

iTrader: (33)

i have my rear o2s and well everything deleted and it still passes all the tests. we had the same problem at my work with a porche, it had a bad computer. that could be the problem, or liek said might wanna have the tune checked in it.

wrencher

iTrader: (2)

It can be tuned so the monitiors pass, but it can also keep the readiness test from being run if not done properly.

WS6FirebirdTA00

iTrader: (33)

so your saying it could have been tuned wrong then, and some things set off?

RPM WS6

iTrader: (3)

Yes, if they mistakenly toggled the test to "off" then it will never pass the test. The tests and the DTCs are set/tuned independently of each other, but some tuners (for some reason) turn both off and it will create this issue.

JRL96TA

With ls1/lt1_edit you can turn off the codes, or the tests, or both correct? So if you turn off the tests when the emissions monitors are set to pass, will they always read pass, and hence always pass the enhanced emission test?