I really do not think it's an air leak.

 

These codes are not there to tell you what specific accessory is at fault, but that the engine is running lean on both left and right banks of cylinders. There could be several causes: an intake leak, a fuel supply problem like a fuel pump not making pressure, or even a bad fuel pressure regulator bypassing too much fuel. I am not talking theory: this happened to my car, and I replaced the fuel pump..which was burned at the connector and it cured my problem. If you want to know for certain about the condition of your fuel pump, spend 5 minutes checking the pressure. If the pressure is good....at least you can check this off as a cause. FYI, I am an aircraft mechanic and I don't assume anything !

 

The next best question is will we ever find out? Aircraft mechanic a good skill!

 

Thanks for all the input. I will check the fuel pressure first. I did replace the fuel filter when I first started having this issue. Figured it was time to replace it anyway! That didn't fix it. I did try the sea foam fuel system cleaner for the injectors and that actually would clear the check engine light until I had to refuel. I will report any updates.

 

I do have same error but only on Bank1. A year ago I had same problem and cleaning the MAF fixed it but this time did not. I smoked the engine through the Break booster vacuum line and I see a small leak of smoke around the bank 1 area of intake manifold. That is the only leak I have found. I like to replace the intake manifold gasket and hoping for someone to provide information on Do’s and Don’t s of this DIY project. (2004 XJ Vanden Plas, v8, 4.2. Not a supper charge). The car is running fine but my California required smog test is due in two months. If not fixed by then I won’t be allowed to renew my registration. I di appreciate any help.

 

Take your car to a "veteran" mechanic... after they charge you a couple thousand dollars looking for leaks, replacing fuel filters, replacing intake gaskets, they might decide a need to verify fuel pressure. DUH ! It a very easy thing to verify. If fuel pressure is good, it eliminates a blocked fuel filter , a bad pressure regulator, a faulty fuel pump or a fuel pump sock filter that might be clogged in the tank with dirt and rust.

 

Well.... sort of. You can have good pressure with poor flow in many of the situations you just described.

 

So I have a fuel test kit that I borrowed from OReilly's but I am not sure where to find the test valve for my car. Can anyone give me some input?

 

Try this link

Link.http://jagrepair.com/FuelPressureTestingxk8.htm

 

I saw this on one of the other threads but when I removed the plastic cover from the driver side of the engine there isn't a valve to connect the guage. I guess the s type is different. It sounds like the s type r has a valve in the front but I haven't been able to find out where the standard 3.0 has the valve.

 

This is for the 3.0

Link http://jagrepair.com/FuelPressureTestingS-Type_sl.htm

 

Gus, your links are not working

 

Thanks it works now

 

Here is what I see when I look for the valve that is shown in your link. I am guessing my car doesn’t have this option. Any other ideas?

 

Sorry I do not have a 2005 car to look at but i thought all the 3.0 were about the same. However, I am not convinced it is a fuel problem and I was an aircraft mechanic.

 

I am thinking I will try to clean the maf sensor and see what that does.

 

Hi,
04 Jaguar VDP, V8, 4.2L.
To fix the Bank1 too rich fault, I cleaned the MAF sensor and tightened all vacuum hoses. Disconnecting battery did not reset the fault. Took it to the shop, they verified the code, reset it, ran it for an hour, no engine fault. They inspect the system , ran vacuum test, could not find any leaks or issues. Ran Drive Cycle and drove around for about a 100 ml, all monitor status ready except the Comprehensive Status. They won’t allow smog check until this signal is ready. I got an extension permit for 60 days ($50) and after 600 miles, no engine code but the Comprehensive Status monitor still Not Ready. I now have to go to DMV every day and get a daily permit as though I have no life!
Would this monitor ever set driving around? What part of Drive Cycle is responsible to verify Comprehensive Status readiness?
Is there a way to speed up the process (if there is a process) that would make this status ready? Thank you in advance for any advice or comments.

 

If it's not setting it's due to something that's not right. I'd get an OBD tool (one with live data) then:
1. check for any pending codes
2. check fuel trims
3. look at the sensors for which you can figure plausible values (try hard, it saves you money) and see if they're OK

Running rich was never a sign of a vac leak - that would be when running lean. You're really not helping anyone by tagging on to a LEAN thread.

So... what codes exactly did you have?

 

You have lean or too much air...These code will normally be triggered by a lose air cleaner box tab, or the hose clamp lose after the maf sensor, or also the induction elbow leading into the throttle body which is a dual clamp set up at the rear. I can assure you it is not a maf sensor, rule of thumb 14.6-1 is your ratio, and at sea level you kilopascals will be 101 which is perfect or barometric should read 14.6 at the map sensor if you have a scanner to read this data. Now if you have the means the absolute best way to check this is via smoke testing...The breather line from the pcv that runs to the lower back driver side absolute manifold pressure plate could have a crack,(its two hoses there one smaller one larger, the larger runs from pcv valve) its is made from loom material, and the small indentments seems will crack as they age. You also have a vacuum line that runs from brake booster to the passenger side of the pressure plate that sometimes will leak. The supercharger to plenum gasket usually seats well and hardly leaks...because it is pressurized...My advice is to smoke her and it will lead you to the promise land..smile...Let me leave you with a final caution, as this leak goes on ,the pcm will respond to the oxygen sensors as they sense more oxygen exiting the exhaust and they increase voltage, the pcm will command the injectors to dump more fuel to compensate for this. This extra fuel will ultimately damage your catalytic converters but first will be the calcium build up on the 02 sensors and the codes will be p1647 bank 2 and p1646 bank 1 upstream sensor failure. The sole purpose of the oxygen sensors is to sense air, NOTHING ELSE. They drive your injectors, so usually if you get a skip the codes will be p0300,p0301,p302 etc...its normally the 02 sensor has failed.. If you have any questions feel free to email me..Hope this helps... and forgive me for the long response...

 

912guy, on a '04 s-type 4.2 are the upstream sensors "wideband" 02 sensors a/k/a air fuel sensors which sense both fuel and air. I was told by a jag mechanic they are.