Hi, I have just got this lovely car ( X-type 2.5 petrol 125,000 miles )The engine management light came on a few days ago so i had it diagnosed today and all the guy could tell me was it was a cat, cat sensors were ok, or spark plugs, not very specific really, i think i can rule out spark plugs as they were replaced about 30,000 miles ago.Can anyone tell me if there is any way to check the cats whilst they are in situ,long shot i know but worth a try. would appreciate any helpful advice please.Thanks.

 

Other members have removed the upstream and downstream O2 sensors and inserted a bore-scope to check the condition of the Cats from both directions.
They are a coated ceramic honeycomb which can fracture and then some portions of the honeycomb structure can then bounce around and turn sideways giving you a restriction......replacement is the only cure.

If however the ceramics are intact, you might instead see heavy deposits on the upstream side that are creating exhaust flow restrictions.
Whether they can be successfully cleaned..........there have been a few treads discussing some treatment options that you would probably read first once you have diagnosed you have a deposit restriction issue.

 

Thanks for the info Mark.Cheers Phil

 

You want the actual code(s) really and a tool such as elm327 is very cheap.

 

Hi, Firstly, thanks for the info for adding more details about the Car, i had put all that info in my profile and not the signature part, i even managed to upload a couple of pics( 72 y o and a technophobe ) hence my inability to use diagnostic tools/apps. I tried the Elm 732 along with the Torque pro app,well,i connected the Elm to the obd plug and eventually managed to sync the 2 and all i got was the app being hi-jacked by ads that refused to go even after several reboots of the app,patience exhausted,i gave up.Anyway,as for the actual code that was showing,the mechanic did tell me what it was but unfortunately i've forgotten it but i'll see him in a few days so i'll get it from him then,thanks again for your help.

 

Hi Again. In my last reply i mistakenly put Elm 732 instead of 327. I have just spoken to the mechanic who diagnosed the car and the code was P0420,also he cleared the code but it's come back again.

 

Scally, based on the code, odds are, it is a sensor. Most of the time that is what it is. Replacing the upstream sensor is not that bad of a job. One tidbit of learning from here, spend the extra few dollars/pounds and get a sensor that is already wired up. There are some unwired sensors out there that "work" (yeah right) for your car. It is a 50/50 shot even if you wire it up right that the sensor will work. Stick with a Denso sensor and you should be good. You will need to replace the upstream sensor on the affected side.

If you want to try and clean out the cat, the thing you are going to need to do first is get the cat hot!!!!! This can normally be done doing a long, hard pull in the car a few times. This is as easy as getting you and 3 of your mates in the car and finding a long hill to try and race up it. Stop at the bottom and give it hell going up. Drive back down and do it again. Do that 3-4 times. That should get the exhaust pretty toasty. That will burn out a lot of what can be burned out. If you insist on a cleaner, then i recommend Seafoam. It will come in a 0.5L can. You will need to get some 4mm clear tygon tubing (about 1.5m long). What you are going to do is get the motor up to temp. You are then going to remove the vacuum line going to the top of the intake and put this hose in the hole and run the line over to the driver's door. About 30 cm back from the end, pinch the hose closed. You will have an open can of Seafoam with the end of the tube in the can.. You are going to start the car and using the gas pedal, you are going to fight to keep the engine running as you unpinch the tubing and let the seafoam start to flow. With about 1/3 of a can sucked into the engine, let the car die and let it suck in some more until it either stops flowing or you reach a 1/2 can. Pinch off the tubing again. Let the car sit for 5-10 minutes. After this time, start the car again. Get it started and not unpinch the tubing again and fight to keep the engine running until the can is empty. Pinch the tubing back off and now Rev the engine up to 3-4,000 RPM. After a few minutes and the car seems to be able to idle again, restore the vacuum line to the top of the intake and take the car for a ride. Use the J-Gate to get down into 2 and 3 gear and get the RPMs up. This is going to help flush out the Seafoam. After about 5 minutes or so, you should be good.

One thing I have not mentioned is that you want to do this away from anything else. Sometimes the car barely smokes, other times it will look like WWIIII. What you are going to experience is a guess. So, find some place away from everyone and use the Seafoam. The car will let you know if it worked or not.

 

https://www.jaguarforums.com/forum/x...sfires-245280/

P0430
Fault Description: Catalytic converter system efficiency below threshold – bank 2 (Bank 2 is the front one)

Follow Thermo's (the "guru") advice/guidance!

 

Hi Thermo, Well, what a great response. I really appreciate your excellent advice,however, when the car was being diagnosed the mechanic assured me that both sensors were working as they should, he even showed me on the screen how they were both in unison and said that if one was different then that one was faulty. So, if both sensors seem to be ok' would your seafoam remedy serve any purpose?.To be honest,what you suggest i do with this remedy really worries the **** out of me for 2 reasons,...1...i read a lot of warnings about putting cat cleaner in these cars,...2..just in case the process damages something else, not because of your remedy itself, it's in case i do it wrong!

 

"Both" sensors out of 4?

 

You guys,please don't think i'm trying to intentionally undermine alI your inputs,i really appreciate it and realise that you have much more knowledge and experience with working on these cars than me,i'm not a mechanic,i am just trying to rectify a problem myself or learn enough about the problem that heaven forbid, i have to take it to a mechanic to rectify and i'll have a good idea if i'm being ripped off or not.That said,i think the mechanic meant (though i might have misunderstood him!) that he pinned it down to the fault being with the 'bank 1' which has 2 sensors and the 'bank 2' having the other 2.

 

Scally, first off, unless you completely disregard what I say and just pour it into the engine, you are not going to make anything worse. The purpose of the tubing is to minimize the amount of Seafoam going in to prevent "something bad from happening". If it makes you feel better, I do it to my own cars. Did it twice to my X-TYpe. Lets say even worst case, you manage to hurt the cat. What you are saying right now is that your cat is trashed anyways. So, what are you hurting? I can understand doing something for the first time that gives you that pucker factor. I guess I call myself the King of Pucker Factor. I do a lot of things that I have seen where others have done something similar, I am just doing it with my own twist.

I say the sensor only because I have seen many like you come through hear saying very similar things and finding out in the end that it was a sensor. Could it be a bad cat. Sure. But, why drop $1000 for a new cat (which, with the mileage on the car, you really should do both to keep the engine load even), when you can replace a sensor for around $50.

I wish you lived closer to me. I would tell you to come over and we would do the Seafoam together and swap out the sensors.

 

Thermo, i get what you're saying about trying the cheaper option first,and the fact that the cats normal life is normally about 70000 miles plus and should really be changed as well because they are the originals i think as no service bills for replacing any of them.. As for the scary seafoam treatment you've reassured me,just one thing i'm not quite sure about is i think there are 2 vacuum tubes going into the inlet manifold, one near the brake servo and one by the firewall, so is there a particular one to feed the seafoam into?

 

Grab the easy one right off the top of the engine. No sense in making this any more difficult than it needs to be.