Hello all! I have my 1997 XJ6 vin # 803841 and I'm have a nightmare of a time getting it to pass inspection. I have it at an independent shop with a mechanic who specializes in Jaguars and he has been working over the past week to get the car to pass. When I brought it to him it had 5 codes (P0460,P0430,P1138, P13B0, and B30F4.) I was told the last 2 are dealer specific codes, if anyone could shed some light on what they mean that would be helpful. But anyway he cleared it and drove it around for about 140 miles till the computer reset and the light came back on for the catalytic converter. So after that he motorvac the engine and flushed the converters and tested to see if it's getting hotter at the output of the exhaust....they both were. He noticed the one oxygen sensor was giving a very slow response so he changed that at the downstream on the driver side. Now he's saying the engine is running lean and that may have been the problem from the beginning. He's saying it could be an EGR valve,or even a new injection pump. I could tell in his voice he was stumped too. Any ideas would be appreciated. Thanks. Btw the car has 143,562 miles on it.

 

The fuel trims need to be analyzed better than "very low response". A smoke test on the inlet plenum and crankcase will find an air leak. Is it lean on one bank or both? Did he clean the EGR? BTW, code 1138 indicate RICH reading.

I don't know what your guy actually said or meant, but based on what you report, I think you need a better guy.

 

The code that keeps coming back is the P1138 which means the 02 sensor indicates rich. Could this mean the secondary air injection pump is the culprit?Could that be the reason the other computer systems won't ready up for emissions testing?

 

Also he did a smoke test(no problems) and a motorvac/decarbonedthe engine. Also replaced a lazy downstream o2 sensor. That let that system finally ready up. But now there's 4 left.
Catalyst - not ready
Evap- not ready
Secondary air injection - not ready
Egr- not ready.

 

So, there are no codes now? How many miles do you have on it since reset. Generally, with a 3/4 full tank, a few runs of a few miles at steady 40 - 45 mph, followed by an idle of a few minutes, then a few more runs at 45 will do it. Usually, it will code if readiness is not passed in 50 miles or so.

 

. I drove it at 55 mph for about 60 miles and the CEL light came on with the code P1138. I'm going to check the injection pump for clogs. What else could it be ?

 

So, according to your initial report, the mechanic (?) changed the downstream sensor on the drivers side. Since it reported to be a XJ6, I am not sure what driver's side means, since the engine banks are usually referred to as front (bank 1) or rear (bank 2). Code P1138 is for the sensor on bank 1, downstream.

Why do you keep asking about the air injection? The code is for slow response on the sensor. I suppose it is possible, with some set of circumstances to get this code for an injection pump, but that is certainly not the first suspect.


The P 1138 code is slow response for S1,2 . If that IS the one he changed, then the wiring for that sensor circuit, including the pins on the ECU connector, need to be checked for shorts or open circuit. The voltage feedback for sensor S1,2 should be graphed with OBD software to see what it is doing. Troubleshoot from there.

https://www.jaguarforums.com/forum/x...8-code-112225/
https://www.jaguarforums.com/forum/x...e-p1138-32542/
I am only trying to be helpful and am not meaning to bust your chops, but you have been asking about this for five years. Have you (or your wrench) done the diagnostic procedures from the book yet? Did you do the re-orientation? Did you test the circuit for continuity? It is hardly a "nightmare" unless you get no results AFTER doing what the service manual tells you to do.

 

I did the live data from all the sensors and their switching as they should. It's not the sensors. I've tested the voltage and they are all grounded with no shorts. They are doing as they are supposed too. Something internal whether it's an EGR valve or secondary air injection pump has to be the culprit because the exhaust it running rich. Not lean I miss spoke earlier on that. The other problem is that I'm getting a P0460 which may also be causing the computers to not ready up. They are supposed to ready up in steps so if one isn't ready it stops the whole cycle and the CEL is illuminated.

 

Is there an injection pump on your 97 XJ6 ? As i recall, all XJ6 comes with the fuel rail controlled via pressure valve regulator and fuel injectors operate via signals send via electric pulse, EGR valve can be cleaned or replace, its a mahor cause to emission issue. Good luck and hope you get to resolve your issue.

 

Well, the code P1138 means the sensor is not switching. You say that the sensors are switching as they should, but is not what the code reports. When you say that, do you mean as measured by a meter, or by charting the parameters? If the voltages switch consistently and you have that code, then then that could mean the ECU is bad.

Since Code 430 refers to cat efficiency, which is a measure of upstream and downstream sensor correlation, I would guess that swapped sensors could be possible. That is one of the "possible causes" for P1138 from the service manual. How did you determine that they were not swapped? Have you done a "re-orientation"?


BTW, the EGR does not result in "running rich" The Air Injector pump could give a rich code, but you would not expect it to always appear only on one bank.

Another possible cause as defined in the manual is a leak in the exhaust system. At one point, you reported a lack of exhaust out of one side. Did you resolve that? That could be an indication of a plugged catalytic converter, which could play havoc with all of the diagnostics.

 

yes they use the same injection pump as the 93-97 corvette. And I'm going to check the EGR valve tomorrow as well as retest ALL sensors to make sure they are switching as they should. Also when they motovac the engine they also cleaned the converters out to make sure they were working. They used a heat gun to measure that the exhaust were much hotter after the catalytic converter.

 

So, you have had the problem for five years, but do not even respond to the question about re-orientation.
Good luck with it all, my friend.