I am due for a VA emissions inspection. I have been driving and trying for weeks now to get my P1000 code to transition to P1111. All the tests have run except the catalyst efficiency test.

According to the DTC summary in the JTIS the conditions for the catalyst efficiency test to run are:

-Normal operating temp
-IAT > 18degF
-varied driving for 3 minutes
-Steady throttle for 30-38mph (1100-1475 rpm) for > 25 seconds

I have tried this many times.

I am getting concerned that either my 200 cell high flow cats, Mina exhaust, 3 lb pulley, K&N filter, low temp. thermostat of some combination of these may be the issue on my 2001 XKR.

If the temp. was too low, I would think the other tests would not run, because they all require normal operating temps. I guess that cats are most suspect, but I really do not want to put the factory ones in unless I have no other choice.

Anyone with insight into this?

 

Cat efficiency is determined by comparing pre- and post- O2 sensor activity. The pre-cat sensors, at a steady state above (typically for most OEMs) 2000 rpm, will produce a sine wave type voltage pattern ranging from (again, typically) 0.3 and 0.7 volts. The post-cat sensors typically reort a very narrow sine wave, almost a flat line voltage. If the post-cat voltages mimic the pre-cat sensors it is considered a fail as the cats wouldn't be doing their job ('lighting up' and burning off unused fuel, etc. which uses up the remaining O2 in the exhaust.) However, if the voltages were mimicking each other a fail code would be generated, rather than not having run at all.

My guess is that there are more parameters required to be fulfilled/satisfied than what you've/they've listed. And it's not unusual for many different makes of cars to have difficulty closing this particular test. It is (again, typically) the last test to be closed in the series. I don't want to be Capt. Buzzkill here but I have seen some cars go weeks and weeks before closing up this test. You may want to consider resetting (clear all codes) and taking a drive for a couple hours that includes driving in traffic and on the expressway - no huge or repeating hills, on and off the gas, etc. I know it's frustrating, I've been there more than a few times over the years.

 

Did you see the Ford driving cycle for the catalysts? (In case its similar) It mentions four different cruising speeds, for 10 minutes each, between 25-40 mph. Couldn't hurt!

 

I am having a similiar situation with my car, I am unable to pass the catalyst as well as evap test. The only thing I don't have is the lower thermostat you have. I drove my car over 650 miles earlier this week & still the tests did not pass so on friday we reprogrammed the ECM & I am tring it now. Please keep us posted as to your progress as I for one am very interested.

 

Tried a bunch of steady driving at different speeds today...still no joy.
VA supposedly allow one not ready monitor...I might have to try to take advantage of that if all else fails.

Jaxkr- This is what seems to work repeatedly to run the EVAP test:
-Gas tank about half full.
-Drive around for 10-15 minutes and get the car well warmed up.
-Turn off engine for 5-10 minutes.
-Restart engine and idle for 13 minutes...do not touch the gas pedal during this period.
-Then as soon as you can, get on the highway and drive at a steady speed for over 6 minutes.

 

Don't confuse the difference between 'passing' a test and 'completing' a test.

 

I am strictly speaking of completing the tests here.

 

Sorry, I meant that for Jax'.

 

has the catalyst monitoring ever been successfully completed since you installed the new high-flow cats?

 

Well, when I installed them I was at P1111, and remained there (with no faults) until I reset the system to do some Evap. system repairs. So I guess the answer is none that I can definitely say occured.

 

One possibility here, is that the non-continuous catalyst monitor is not running because of another fault present in the system that a generic scantool cannot see. Some faults make the system stop running some obd monitors if the fault MIGHT render the monitor results questionable. In that case, it just doesn't run it. It may well be related to the cats you installed.

You might have it interrogated with the Jag IDS/SDD.

Just a thought.......

 

She still reads P1000, and still shows catalyst efficiency not run....but it was good enough to pass Virginia emissions testing !

Yippee !

 

Personally, I would want to get to the bottom of what's going on that prevents the monitor from running.........

Cheers,

 

My first priority was to keep the car on the road, but you do raise a good point. Ths car gets fairly light use, so I wiil first just give it some more time.

I have no codes, and she runs very well. I have done some looking at the OBDII real time monitors and nothing that seems out of line.

This car has has some moderatelty significant mods, especially when you take them all together....I really suspect that is the issue. I am definitely going to keep the original parts in safe storage.

One thing I might look at a little further, though, is the EGR. I have an Autoenginuity scanner and though there are no fault codes, it reports a fail on the EGR test. Now according to Jag doucmentation, the EGR test is not a standard Mode 06 test for this car (and if it truly failed, it should not have passed emissions). Also on another forum someone posted that a 2002 XKR also report a test failure of EGR with Autoenginuity with values similar to mine and he believed it was bogus also. But it is still a possible clue and worth a little more investigation.

 

I just can't get passed the idea that your AutoEnginuity isn't telling you everything. If it tells you the EGR monitor failed, that's a fault, and it should record a fault. Likewise, as I mentioned before, there may very well be something there [a fault] that is preventing the catalyst monitor from running. Just to refresh, here is an excerpt from something I saved some years back.
**********************************
The typical approach when checking a vehicle for codes is to plug in a code reader or scan tool
into the diagnostic connector on the vehicle to see if there are any codes present. If the scan
tool can also display history or pending codes, the next step might be to check for any old codes
or pending codes in the PCM, especially if you didn't find any current DTCs. From here, you
might then use a scan tool to read the freeze-frame data if a DTC is present, to read live system
data while the engine is running, to perform various interactive system tests and/or to clear
codes.
Most technicians are very familiar with Modes 1 through 4 because these are the scan tool
modes that are most often used. You check for codes, you look at system data and freeze-frame
data to figure out what's going on, and then you clear codes to turn off the Malfunction
Indicator Lamp (MIL) and to verify a problem has been fixed. If the MIL stays off after you've
made repairs, you assume everything is fine and send your customer on their merry way. But if
the MIL light comes back on, then you're back to square one and get to repeat the process over
again to rediagnose the fault.
One of the main drawbacks of OBD II is that the PCM won't set a DTC and turn on the MIL light
if a fault is still present until after the vehicle has been driven. With most faults, it takes at least
two consecutive trips to set a code and turn on the MIL light when a fault is present. The reason
why OBD II is set up this way is to reduce false codes and to make sure there really is a problem
before it sets a code and turns on the MIL light. The downside of this approach is that you get a
lot of comebacks. You think you've fixed the problem and have returned the vehicle to the
customer, but several days later the MIL lamp comes back on and the customer is back in your
face. What happened?
OBD II non-continuous monitors will not run if a fault has already occurred in a sensor or other
system monitor that is needed to perform an accurate test. For example, the catalyst monitor
won't run if there are any oxygen sensor codes. The catalyst monitor needs a good signal from
both the upstream O2 sensor(s) and downstream O2 sensor(s) to verify the operation of the
catalyst converter. If any of the oxygen sensors involved are misbehaving, OBD II will suspend
the catalyst monitor until the oxygen sensor codes are gone.
The catalyst monitor compares the switching activity of the upstream and downstream O2
sensors to see if the catalyst is operating at peak efficiency. If the converter is doing its job
effectively, the downstream O2 sensor signal should be flatline with little switching activity. If the
catalyst is getting old and isn't working so well, OBD II will detect the increase in switching
activity and set a code once it exceeds a certain threshold.
The catalyst monitor requires specific driving conditions (enabling criteria) before it will run, so it
make take several days or even a week or more of driving before all the conditions are just right
to run the monitor. As a rule, the engine must be hot (170 to 230 degrees F), the PCM must be
operating in closed loop and the vehicle must be cruising at part throttle from 25 to 35 mph.
There also must be no DTCs present for the oxygen sensors. Under these condition, the catalyst
monitor will usually run within 15 minutes or less.
The story is similar for the EVAP monitor. The EVAP monitor checks for vapor leaks in the fuel
tank and EVAP canister plumbing. The EVAP monitor also has a long list of requirements that
must be met before it will run, things like a certain number of hours of "cold soak" with the
engine off before it will run a pressure or vacuum test to check for fuel vapor leaks, the ambient
temperature has to be from 40 to 90 degrees, the fuel tank must be 1/4 to 3/4 full, etc. When all
of the required enabling criteria have been met, the EVAP monitor will run and check for any
faults. As with the catalyst monitor, an EVAP problem won't set a DTC until the same fault has
occurred twice under nearly similar conditions.
**********************************
Keep us posted, I'm really curious how this plays out. Do you know anyone who has access to the Jaguar IDS/SDD?? That may be the only way to completely put this to bed.

Cheers,

 

Thanks for posting that info. It might take a while, but I will try to get to the bottom of the issue.

 

Well, had not had the car on the scanner in several months. Put it on today and....P1111...all tests closed.

Soooo, I am happy to say that my aftermarket Nameless cats passed catalyst efficiency...eventually!

 

Cool! Thanks for reporting back to tie this up.

I'm convinced now, that the new cats probably were causing the component monitors to fail to run. There is a "burn in" period for the catalysts that can cause issues; I'm finding that more and more as time goes on. Even some of the new cars are showing some instances of 'sub-feedback' faults at really low mileages. Once we dog them for a few miles the cats burn in and the faults stop. Even noticed the monitors being lazy on a couple of replacement cats since last summer.

Learning curve just never stops, does it??

Cheers,