Hey Guys,

I am trying again to get help from the board. I am running out of ideas.

Ok a brief history.

In May my inspection was due. Took it to the same place I have used for years. This time it failed because I had the CAT and EVAP I/M monitors read as "NOT READY". The tech told me to drive it. I had replaced the CAI a few weeks before so I had the battery disconnect. Ok no problem. About 100 miles I take it back. Failed again for the same NOT READY on the CAT and EVAP. Took it and drove it for 200 miles. Failed I drove it some more and put 300 more miles on it. I don't drive every day so it takes time to rack up these many miles. So now I am in the middle of August, I take it to the dealer to get it inspected. I have heard that you might have to do a "force reset" of your PCM in order to get the monitors to reset. The dealer report shows the same Not Ready IM monitors. So I asked the tech if they can do a reset of the PCM. He had no idea what I was talking about. I talked to another tech and he had the same dumb look on his face. They told me to drive the car some more!!! Really! So now I decided to replace the downstream Oxygen sensors and pick up an OBDII code reader so I can check on the Monitors my shelf without having to pay $28.50 for another inspection. I give the car to my parents for a week to drive the hell out of it. They drover it for a week and ran it all the way down to empty and checked the monitors daily. No luck. Now I am pissed so I replaced the cats and the upstream Oxygen sensors. Drove the hell out of it again for over a week. Driving it multiple times a day. No luck.

I talked to Bill Curlee and he told me to check the battery and alternator. They checked out ok. Car is getting enough volts while running. 14.5v from the alternator at the back of the alternator and at the battery. The terminals are tight. The battery with a cold car has 12.5volts and during crank it drops to nothing lower then 10.7 volts. So the PCM is not reseting during startup.

I checked everything I can on the evap system and the lines to and from evap solenidor are tight. I cleaned the electrical connector with contact cleaner.

I have head that the evap system will only check once you have a full tank and you get below 3/4 full and the outside temp is below 80. Well if that last part is true then screw it cause this is the hotest summer in TEXAS in its record keeping history!!! Even at night it does not get below 80.

During the whole process from May to today, I have had zero DTC codes. I check daily and not one, never, nothing!!!

So what do I check from here. Battery is good. Catalyst system is brand new. Upstream and Downstream Oxygen sensors are brand new. I replaced the fuse in the battery compartment for the oxygen sensor system. I drive 3 or 4 times a week normally between 25 and 30 miles round trip. I have filled it a dozen times. What is left???



~~~~HELP~~~

 

Something else is wrong and until that code is cleared it won't let the monitors reset. I had the exact same problem with an Acura. I finally bought a 'code checker', saw the other code and cleared it. A few miles later everthing reset. I don't know what your problem could be but the Acura's was a mis-fire problem. I put in new plugs and when the mis-fire was gone, the rest of the monitors were able to reset.
Hope this helps.

 

Well, my autoenginuity software for my laptop lets me run tests on the EVAP system-to cycle it like the test the car does on itself. Thypically the car doesn't run the EVAP test till the tank is down on fuel some (so there is gas fumes to pull out of the tank). You need to get someone to try to actually engage the EVAP system to see if all the solenoids that control the system are working. I would think that the ECM would try at some point to run the test if not I would suspect an OBD code would get set.

You need to check you local laws, many states will allow 1 or 2 MIL tests to be NOT READY and still be OK.

 

I would agree however I am not getting any codes being set. So according to the OBDII reader and the in car DIC read out there are no codes on the car.

 

Texas will allow it to pass with 1 MIL NOT READY. Just trying to get one of the two to reset to READY.

 

Follow these steps to complete the readiness cycle:

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

To perform an OBDII Driving cycle do the following:

(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.

 

Sorry should have added to my long rant that I did this repeatly. while setting in my drive way and while driving out in the country. It was late last night when I posted.

 

Did you follow the exact order as listed?

 

Yup, though I must admit it is kinda hard to know if you are going 55mph when you are not driving down the road and living in a city does not make it easy to drive at 55mph for 5-8 minutes then coast down to 20mph then accelerate hard to 55-60mph.

 

The issue isnt if the alternator outputs the correct voltage when the car is running,, there could be a problem with voltage supplied to the PCM / BCM when the car is being started.

If the battery is checked/tested good, one last thing to try is to rebuild your ignition switch... If your NOT seeing a DTCs, your not resetting DTCs and have not disconnect the battery, the only other power disruption is a faulty ignition switch:

-C5 ignition Switch repair - http://forums.corvetteforum.com/c5-t...ch-repair.html

 

Those " readiness tests" are a pesky bunch---Any car around 10 years old will usualy have some of them fail or will take forever to set to "ready"
The Evap ones are the worst ! Also depending on your mods the "heated catalyst or 02 tests" are troublesome--Another one is if you have LT headers you will get false misfires and the misfire test won't set--

IF your car appears to be running fine---Ultimate PERMANENT fix would be to have a tuner with HP or EFILIVE--make all the readiness tests set PERMANENTLYto "READY" !!!! No more issues with them ever !!!--
(don't ask don't tell )

 

I am going through the same crap.

I had a crack in the evac solenoid, so it wouldn't hold vacuum.

Been driving trying to get the STFT B1 & B2 % to come up with a # so that Mr. Smogmans machine will recognize the rear O2 sensors are working.

I have an OBDII monitor, but it won't exercise the evac system.

I was throwing a P420 code before I replaced the evac solenoid.

 

420 is a vacuum leak. He's not getting a code, his test isn't running. I've been doing more reading on the test and the gas tank level has to be between 15 and 85% to run (as well as several other criteria). BUT, is the ECU can't determine the gas tank level, it won't run the test.

OP-does your gas guage read OK???

 

It threw a p420 code when I opened up the leak.

Before that, it would show up on Mr. Smogmans machine as evap circuit not working, but no code.

 

Yes, No problem with the gas gauge. I typically run Seafoam through the gas tank one every other month to make sure everything is ok.

 

I've had the switch out before and rebuilt it according to the post. I have not done it lately. I guess I will tear into that tomorrow.

 

P.M. sent

 

Thanks Dave, I will give it a try.

 

I had this exact issue with my 2004 Silverado. I could not get the OBD tests to set after repeated attempts at clearing codes and disconnecting the battery before running the OBD driving cycle. I had enough so I took a gamble and replaced the ECU.

Since replacing the computer the emission tests set just like they should. But now I started getting a CEL. Come to find out the knock sensor was bad.

The old computer was definately messed up as it could not set CELs or the OBD tests.

Hope this helps, don't rule anthing out.

 

Im just down the road from you, if you want to meet up just send me a PM. I have something that will plug into the OBD2 and clear anything going on, a scanner basically. Had to use it to clear off my PO410 before getting the BS inspection around here.