Cannot figure this out - Emissions....

[bruceb]

If the O2 senors do not fix it, I would check the Mass Air Flow Sensor. If it does not report the proper amount of air going into the engine, then the air/fuel ratio will go very rich. The chances of the converter being bad are small and if you do need one, check out Mangaflow. They have very good high flow converters which are usually bolt in units and most of them will even meet requirements for use in California (for a car that is registered or inspected there)

 

[sontakke]

Replacing parts without spending time to diagnosis but just hoping to fix a problem is always a great idea I am sure eventually, OP will have it nailed. Let me give him the list of parts to replace

O2 sensor(s)
MAF
Catalytic converter
Charcoal Canister
VSV
PCM

Feel free to extend this list.

 

[cardiac]

The rear sensor is NOT supposed to switch often but it should switch slowly like once after few seconds or so.

Did you do the test I had requested you to do?

Yes, it is only showing the catalyst as not ready. Everything else is ready, and there are no CEL on or codes, and that is cold in the morning after sitting all night. With nothing else showing not ready, I'm confident that the ECU is getting and maintaining power.

I'm not a parts switcher, and don't like doing that. So I have it at shop that does a bunch of emissions work in our city (Friends son owns it). I just don't like admitting defeat and going to a shop.....

 

[cardiac]

Replacing parts without spending time to diagnosis but just hoping to fix a problem is always a great idea I am sure eventually, OP will have it nailed. Let me give him the list of parts to replace

O2 sensor(s)
MAF
Catalytic converter
Charcoal Canister
VSV
PCM

Feel free to extend this list.

I definitely don't need the list extended Thanks for the offer, lol

 

[sontakke]

So at this stage, is it only the catalyst which is NOT READY? My Maxima which took a month and thousands of mile to complete the CAT test. Fortunately, in our state up to two incompletes are allowed for 2000 or earlier models.

 

[cardiac]

So at this stage, is it only the catalyst which is NOT READY? My Maxima which took a month and thousands of mile to complete the CAT test. Fortunately, in our state up to two incompletes are allowed for 2000 or earlier models.

Yes, just the catalyst. At this point I have done the Ford drive cycle quite a few times. Indiana just changed it to ZERO incompletes last year. Prior to that it was the same criteria as yours....

 

[shabby]

Catalyst 7. Drive in stop and go traffic conditions. Include five different constant cruise speeds, ranging from 40 to 72 Km/h (25 to 45 MPH) over a 10 minute period. Executes the Catalyst Monitor.

Just keep doing this, btw how many miles ago did you reset the ecm/pull the battery?

 

[SparkyJJO]

This is the stupidest thing with e-check. You do stuff by the book and have no indication anything is wrong (no lights no nothing) but they fail you anyway because "incomplete." The heck are you supposed to do if it stays incomplete? Just throw tons of money at it randomly replacing stuff hoping it'll finally be happy, while hoping you can figure it out in time before your plates expire and you can't get to work anymore?

So glad there is no e-check nonsense here.

 

[cardiac]

Just keep doing this, btw how many miles ago did you reset the ecm/pull the battery?

Never pulled the battery. After the very first test I tried to reset the ECM with my scanner but that didn't do anything and we have driven it probably 500 miles since, including doing the Ford drive cycle numerous times.

SparkyJJO, I agree. We are being singled out and discriminated against where I live. There are 92 counties in Indiana, and there are only 2 that require emissions testing. In fact, I live about 1 mile from LaPorte county, which does not require testing. How is the air sooooo much better 1 mile to the east of me?

 

[sontakke]

Look at the mode 6 data and see if there is anything there which is suspicious. It is possible that one of the enabling criteria to run the cat test is not being met. Now one would think that the programmer was smart enough to flag it by setting some CEL but this may be such a borderline condition that (s)he might have overlooked it. Most in the programming field understand those kind of bugs. For example, suppose cat test can only run when the coolant temperature is over 200F but the CEL for setting temperature not reaching normal could be set at 170F. Something like this will keep cat test from running without any other issue.

Usually, when a county insists on emission testing, they designate few extremely sharp shops who can figure this out. Call the state EPA (or equivalent) and get few names.

If you own a good scanner/code reader, you might be able to go further but otherwise the time has come to get real professional help.

 

[LTC8K6]

Went to my buddies place and hooked it up to his Snap-on scanner and it showed no fault codes, which is no surprise. What it did show is that the downstream O2 sensor sat at 800 microvolts, and didn't vary much, where the upstream sensor went between 50-900 microvolts as the car ran.

So, that is showing a rich condition, but is it a bad sensor, but still within the specs of the sensor, and doesn't trigger a CEL, or is it showing rich because the cat is bad? It appears that the converter and the O2 sensors are original. As cheap as they are, I think I'll change the sensor #2 and see what happens. The cat isn't cheap, and it looks like a real bear to change....

What about something like the coolant temperature sensor being bad?

That could make things "not ready" permanently, since the ECU doesn't think the coolant/engine is up to temp.

 

[bruceb]

Some cars have 1 coolant sensor which works both the gauge / idiot light and also talks to the engine computer. Others have 2 coolant sensors, 1 for the computer and the other for the gauge / idiot light. LTC8K6 may be on the right track, but I still think if the O2 sensors do not fix it, that it may be the Mass Air Flow Sensor

 

[cardiac]

As sontakke said, I have opted for an emissions expert. I have been to them in the past for things that I just couldn't take care of. It's owned by a friends son, and has been in business since the 80's. He surely isn't the cheapest around, but he guarantees everything he does and it's done right. He can't get to it until Monday. I will keep everyone update on what he finds. You guys are awesome, and thanks for the help!

 

[cardiac]

This has got to have been the biggest pain in the ass that I've had in 40 years of backyard mechanics. Long story short: It was the throttle position sensor. The car was idling about 100 rpm too high and that was enough to not allow the catalyst monitor to "Be ready". Yet the TPS was not bad enough to trigger a CEL Dropped the idle, drove it an hour, and my mechanic got it to pass the test. It took him about 3 hours to get to that point though.

Thanks to all who contributed in my painful journey!!

 

[sontakke]

Wow, that is some screwed up programming! Your emission expert is very talented to notice the 100 RPM difference. I do not see how anybody else would have found it.

 

[LTC8K6]

Ford has some quirks.

If the fuel level is not at least 15%, there is no misfire monitoring on a Ford, for example.

 

[tortillasoup]

This has got to have been the biggest pain in the ass that I've had in 40 years of backyard mechanics. Long story short: It was the throttle position sensor. The car was idling about 100 rpm too high and that was enough to not allow the catalyst monitor to "Be ready". Yet the TPS was not bad enough to trigger a CEL Dropped the idle, drove it an hour, and my mechanic got it to pass the test. It took him about 3 hours to get to that point though.

Thanks to all who contributed in my painful journey!!

that definitely makes sense! Car needs to actually idle @ designed speed in order to conduct all of its tests. I've seen this issue on more than one occasion but unless you're looking for every little single problem the car can have, a 100 rpm difference is definitely easy to ignore.

 

[cardiac]

While there is no doubt that the engines today start easier, run smoother, and definitely last longer, I sure miss the days of points and condensors, one coil, mechanical fuel pump, etc. A 100 rpm change took me 2 weeks to have tracked down, and I am sure lucky he found it...

 

[JEDIYoda]

While there is no doubt that the engines today start easier, run smoother, and definitely last longer, I sure miss the days of points and condensors, one coil, mechanical fuel pump, etc. A 100 rpm change took me 2 weeks to have tracked down, and I am sure lucky he found it...

see there really is a God!!

 

[sontakke]

But think of this way. Suppose you did have the car with points/condensor/single coil etc and it flunked real tail pipe emission. Can you imagine what would it entail to find and fix the problem? After every try, you would have to put the car on the testing station. I suspect, it would have taken longer to find and fix problem if you had to visit (and pay) the testing station. I mean you don't have your own 3-gas analyzer, do you?

 

[cardiac]

Yes, there is a God.... Sontakke, no, no 3 gas analyzer in my garage, but I do have a few 4 gas monitors down at the fire station . Wrong gases, though!