MY 02 Hawk failed inspection an 1 hour ago due to (see below) I will post the sheet later when I scan it.


02 sens - not ready
02 sens htr - not ready
2nd sys - not ready
evap - not ready
catalyst - not ready


Everyhting else says ready.

mods are 2800 stall, GM crate LS6 engine, ported maf, cut-out, hypertech.
The car is rarely driven and all other pieces are stock i.e. complete exhaust, manifolds, and cats etc....

WHAT THE F***!!! The car runs fine and throws no codes...

2002 Hawk with 29,933 miles on car and 6,000 on new motor.


I have put the stock programming back in and disconnected the battery for 20 niutes and I am going to go cruise around for a while. Please post up and I will check back in a little while.

Thank You,
Drive Through...

 

probably just a bad O2 sensor, most likely one of the rear ones.

 

When you disconnect power to the PCM, or reflash it when tuning, it resets the readiness flags to 'incomplete/not ready'. You need to do a few drive cycles to get all the tests to complete. Every car is a little different, mine takes about 4 cold starts and ~80 miles of driving to reset all my readiness flags after a PCM reflash or battery disconnect. Even after following the OBD drive cycle to the letter, it still takes mine a little while to complete.

O2 heater, Cat test, and EVAP take the longest for me.

Have you done any custom tuning? If someone turned off the tests for those DTCs then your readiness flags will never set. You can turn off the SES light (set to Type X) for a DTC and be just fine, but never toggle the "test" to off otherwise it won't run that readiness moniter and you'll have a constant incomplete/not ready status for that moniter.

A bad O2 sensor will not cause an O2 DTC test to not complete, unless a previously set DTC prohibits it from running. If you have no codes, then this is not your issue. The whole point of the test is to run and identify any faulty components, if a bad O2 sensor caused a test to not run then no one would ever get O2 DTCs

I've also had issues in the past with my O2 heater test not running due to a low battery voltage. Is you battery old? Do you have access to a load tester?

Try a few cold starts, plus some regular driving for a week or so and all the tests should be complete unless you have voltage issues or bad tuning.

There are certain requirements for DTC tests to run. Usually, the ignition voltage must be between 10.0-18.0v, certain other DTC tests can not be running or failed, and some require the start-up ECT and IAT to be within 14.5*F of each other, and not above 122*F (mostly O2 heater related tests).

Hope that helps......

 

RPM WS6, great post!

 

I will try what I can. If not can I LS1 Edit the whole thing from MTI?

 

RPM WS6, you are exactly right! The drive cycles need to be done.......

 

The car only gets driven about once a month so I guess I should maybe drive to work a couple of days and see what happens.

 

I was thinking that you shouldn't of disconnected the battery before inspection. I remember being told that the car has to be driven at least 7 days before they can inspect it again, after disconnecting the battery. So the driving cycles make sense. Looks like you will be driving that beaut back in forth to work!
Hope it doesn't rain on ya!

 

I do ET in Ga. and we see this a lot,someone replaces the battery/alternator or has work done just prior to the inspection that requires disconnecting the battery and fails for "monitors not ready", we always advise them to drive 150 miles combined highway/city driving and return for their free retest within 30 days. In Ga. 96-2000 cars/light trucks can have 2 "not ready's" and pass, 01's and up can only have 1 not ready and pass(usually the cat takes the longest).

 

Somewhere there's written the official GM
driving cycle, and if you did this by the book
it should result in the minimum time to all-
systems-go. I know I've seen it but I can't
remember where.

 

I think I've found it.

A complete driving cycle should perform diagnostics on all systems. A complete driving cycle can be done in under fifteen minutes.


This is how to perform an OBD Type II Driving cycle:



1.) Cold Start. In order to be classified as a cold start the engine coolant temperature
must be below 50°C (122°F) and within 6°C (11°F) of the ambient air temperature
at startup. Do not leave the key on prior to the cold start or the heated oxygen
sensor diagnostic may not run.



2.) Idle. The engine must be run for two and a half minutes with the air conditioner on and
rear defroster on. The more electrical load you can apply the better. This will test the
O2 heater, Passive Air, Purge "No Flow", Misfire and if closed loop is achieved,
Fuel Trim.



3.) Accelerate. Turn off the air conditioner and all the other loads and apply half throttle
until 88km/hr (55mph) is reached. During this time the Misfire, Fuel Trim, and Purge
Flow diagnostics will be performed.



4.) Hold Steady Speed. Hold a steady speed of 88km/hr (55mph) for 3 minutes. During
this time the O2 response, air Intrusive, EGR, Purge, Misfire, and Fuel Trim
diagnostics will be performed.



5.) Decelerate. Let off the accelerator pedal. Do not shift, touch the brake or clutch. It is important to let the vehicle coast along gradually slowing down to 32km/hr (20 mph). During this time the EGR, Purge and Fuel Trim diagnostics will be performed.



6.) Accelerate. Accelerate at 3/4 throttle until 88-96 km/hr (55-60mph). This will
perform the same diagnostics as in step 3.



7.) Hold Steady Speed. Hold a steady speed of 88km/hr (55mph) for five minutes.
During this time, in addition to the diagnostics performed in step 4, the catalyst
monitor diagnostics will be performed. If the catalyst is marginal or the battery has
been disconnected, it may take 5 complete driving cycles to determine the state of
the catalyst.



8.) Decelerate. This will perform the same diagnostics as in step 5. Again, don't press
the clutch or brakes or shift gears.

 

I will try this during the week. Jeremy I disconnected the battery after I left the Inspection place.

 

Good thread. I have to getmine next month and not sure how it's gonna go since I'm not tunned with the new cam and running rich. I'll follow that cycle though.

 

Got my 99 Z IM/240 inspected yesterday, and the tech and I had a 30 minute conversation about exactly this, and he basically revealed the same info as posted here!

He said the IM/240 test needs a minimum of 3 cold start and drive cycles, worth of data to sample from, in order for the test to be considered complete.

 

No, don't flash the PCM or disconnect the battery. It's likely one of those caused it.

 

clearing emissions dtc's with efilive will reset some readiness bits too.

gotta drive her to get them back

 

Thanx for the help/info...

Since I have been only driving it around the block once a month I guess I need to drive it more before inspection time. Damn, the luck! You try to keep it put up and the car itself is telling you to drive her.