Drove my Granddaughters 99 Blazer from Corvallis Oregon, to Southern California. Now I need to get it smogged. Did oil change and air filter in Oregon before trip. Noted a small leak in Coolant, but kept overflow tank to proper level, and it made it the 1000 miles easy. No overheating at all. As a matter of fact the temp gauge is marked at 100 and 210. It never seems to make it even close to the middle of those two marks at 155. It is always around 125 135.

Also the car had a new battery put in a while ago apparently.And the car needed a JUMP to start about a week before we drove it to Southern California.

This vehicle has a RECONSTRUCTED stamp on the pink slip, so not sure what history of vehicle is. Probably similar to SALVAGE title here in California.

Took it in for SMOG and all of the NO, CO, etc passed, but the FUNCTIONAL Failed because I had 3 monitors giving INC

Currently Catyalyst Mon INC
EVAP System Mon INC
Sec Air System INC

Have done the drive cycle where I start it up and idle for 2.5 minutes with AC on, and Rear Defroster. Then get to the Freeway and do 3 minutes at 55 and coast to 20, and then do 55-60 for 5 minutes and then coast to 20.

Have done the DRIVE CYCLE 2x now, and still have those 3 as INC. I have read it takes a long time, sometimes to get them to reset.

I had filled the tank with gas, and added some FI cleaner. So now the tank is getting down to the 3/4 level, and I have read that the EVAP test won't take place unless tank is between 1/4 and 3/4 approximately.

Also worried, that somewhere I read, and as I was told by the smog guy, that 2 of sensors can be INC and will pass but not 3. But if it fails the next time Catalyst Mon can't be one of them that are INC. If it gets down to 2 or less, that is.

Thanks for any ideas

Maybe there is no thermostat in this car, what is the normal operating temperature?

 

Normal operating temperature is 195*. Usually it will throw a cel with code p0128 if it is running that cold. It sounds like the thermostat is stuck open.

 

As mentioned, operating temp needs to be higher, (stat probably not closing all the way, needs new one). Stat begins to open at 195F and normal operating temp is very close to 200F.

Certain circuits and systems are monitored continuously by the powertrain control module, (PCM). There are other circuits and systems that are only monitored when a certain driving pattern is duplicated. All of the monitors will eventually run and complete under normal driving situations. Some can take considerably longer though, due to the complexity of the necessary driving pattern involved. To force all of the monitors to run and complete, the General Motors Driving Cycle must be performed exactly as written. You do not need to do the steps in order, but each step must be performed. If performed correctly, all monitors will run and complete their tests. Each step tests different things, and the drive pattern that it describes must be duplicated exactly as written. If not, one or more monitors will not complete. With practice, and careful planning, a driving cycle takes about 15 to 20 minutes.

You mentioned about fuel level needing to be a certain level... that is one of the requirements for the EVAP monitor to run. Fuel level must be between 15% and 85%, or the monitor won't even start to run. Once any monitor starts, if the drive pattern varies away from the required pattern, the monitor will stop running. The PCM will continuously "watch" for the necessary drive pattern to be duplicated, until the monitor runs and completes. Complex? Yes. Easy to perform a driving cycle? Not at first, but with practice, it can be done

 

Replaced the Thermostat with a 195 Degree Type, that if it sticks will stick open.

After the Blazer sat all day, and just before dark, I started the Drive Cycle. By the time I had idled and had AC on, and Rear Defroster on, and made it to the Freeway to 55 for 3 and glide to 20, and then 55-60 for 5 minutes and glide to 20, the Gauge was up higher than I had seen it during the whole 1,000 mile trip from Oregon. A tick or two down from 210. My guess 190-195.

Got home and now only 1 of the Monitors are INC.

The Catalyst Mon is now OK
The EVAP System Mon is OK
the Sec Air System is still INC

But if all stays the same this should allow it to pass. Especially if this has no effect on the low #'s that I got on NO, CO, and HC. already the first time.

Thanks.

From what I read the Sec Air System is something that happens at warm up??

Anything I should try to do to clear this last one to OK?

 

Temp is now where it should be! Running cold will destroy fuel mileage.

Sounds like you performed the cycle just fine, but secondary air should have completed during the driving cycle, (not sure why it didn't). Is the check engine light on? Is there a DTC in the pending file for secondary air? That system is prone to failures, and that's one of the reasons they stopped using it.

The secondary air system pumps fresh air into the exhaust during certain rich conditions to help the upstream catalytic converter do its job. The system was used starting in 99 and I think through 2002, to meet 50 State EPA requirements, (California). If the peoples republic of California allows one incomplete monitor, you should be fine, unless the check engine light is on. Most States that require emission tests will issue an immediate "fail" if any of the monitors are incomplete.

 

From what I have been reading and told by the SMOG guy that failed me, is that I must have more than TWO that are INC.

He said they allow TWO.

And from what I read ONE of them can't be the CAT.

So looks like were good to go. I still have Sunday to give it a go, and Monday morning on my way to the 7:30 am opening of shop.

It will be nice to have it pass.

Thanks, for suggesting Thermostat. Once you said it, it seemed obvious.

 

Success: Car PASSED California Smog Test.

Caveat: About 1/2 mile from Smog Station on the way home I look down, and I see the "Check Engine Soon" light on. I call back, and smog place says that it must have thrown a code.

So when I get home, I see that ALL 9 of the monitors are OK. But 1 Code Found.

So my guess is that the Sec Air System that was INC, went to OK, which it did.

And the car passed smog.

But on the way home the car thru the CODE P0410 Secondary Air Injection System.


I am just glad I can now transfer the vehicle and that it did not throw the code during the test.

Now to see if I can troubleshoot the P0410 Code Secondary Air Injection System.

Also, Autoclub on phone said that they will come out to car and check VIN and the California Emission Sticker, which I can see referring to California.

Thanks, again for Thermostat answer, and I am sure there will be lots of threads on P0410 and how I need to treat it.

As a Side Note: I just read that moisture or water could cause the pump which is below the radiator to freeze or act up. This vehicle does have a Coolant Leak, which is not enough to stop the car from going 1,000 miles but does leak towards the front. Guy at smog place thought it was coming from above the water pump. But I suppose if it has been doing it for a while, I will have to check this pump out.

 

Water in the air pump has always been a problem with the secondary air system. It usually gets into the motor and seizes it up, and then pops the fuse. There are two steel check valves with rubber hoses going to them from the pump. They should only allow air flow in one direction, from the pump to the exhaust system. If the check valve inside doesn't seal, exhaust travels back toward the pump and burns up the rubber check valve, and the rubber hose. Usually have to remove the valve to check it.

This link might help with diagnosis: https://blazerforum.com/forum/diagno...plained-35146/

The flow chart is 11 pages in length: not a simple, quick a minute process