My 2004 X type, 114k miles, has had issues for over 2 years, hesitating, throwing codes, check engine light, and lately going into limp mode more and more frequently. After researching the issue on the forums and paying a worthless shop to find the issues, (they didn't) I finally determined it was a Throttle Position sensor and Throttle body problem. I bought a TPS (probably Chinese) on Ebay and tried it but the car wouldn't run at all with it, in any adjustment. So purchased a throttle body from Parts Geek ( not the cheapest one but one they recommended for 3.0). With the new throttle body on the car and all faults cleared, the car started and ran PERFECTLY. Prior to fix, throwing codes for TBS 1122 and even trans fault, and more. All cleared and none coming back. So relieved to have this issue behind me. Thanks to Thermo and all who contributed forums on this issue. They all contributed to my success with this repair. Hope this helps others.

 

Well after driving the X Type around it runs great but still occasionally, and without warning goes into limp mode and shutting it down and restarting is the only cure. This car has had all vacuum leaks checked and plugged. A new battery (AGM), battery cable grounds checked and cleaned, Still is throwing the 1122 and 1000 code when it goes into limp mode. Any further suggestions? It must have a connection loose or dirty somewhere, but where. It went to limp mode once when brakes were applied. Go figure? A shop could not find the problem and it appeared the throttle body cured it but only for two days. Ideas?

 

I would not worry too much about P1000. I think I got P1000 on all of my Jags and nothing is wrong with them.

I googled P1122 and I VERY quickly few over the contents of the following thread, which is about P1122 on the X308:
https://www.jaguarforums.com/forum/x...il-safe-57600/

Flying over that thread and remembering, what you wrote above, especially your sudden P1122 problem, which then disappears for a while:

My bet would be that you have an intermittent contact issue with a connector to/from the TB or the TBS. That would explain everything.
Intermittent connection issues are the most difficult to find. I found one on my X-Type: One of the MANY pins inside of the big blue connector to the ABS module had some kind of intermittent connection issues, which caused the ABS light to on again and again. And there was no fault on that connector to be seen.

I just measured for continuity with a multimeter again and again, until I found that bad pin and I replaced the single bad pin in that connector.

My approach for your problem would be the following:
Spray CRC 2.26 onto of the the possible suspect connectors (i.e. open connector (have a good look, too, if you can see something), spay it and reconnect it).
If that fixes your problem, no need to spray the next connector. Just remember, which connector you sprayed, and if then after a long time the issue returns, you know, in which connector you need to investigate even more thorough regarding those pins.
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PS: While "talking" about connectors and how critical they are...: I am following Tavarish's flooded P1 (EVO) rebuild. In Part 11 he showed, how he "cleaned" the harness (loom). Now that was silly, and accordingly I left a comment about that on his video,,,:

I am kind of worried that you consider reusing the harness (loom). I worked for automotive manufacturers, I specialized in switches and contacts. Also, I too use vinegar only (no salt) to clean off oxidation, I mean like the worst rust ever, but I would never do that on electrical contacts, but I do that on thick rusty metal parts, which I then coat with paint - sometimes just clear coat. Note that I once left a scythe submerged in vinegar for 3 days and the biggest part of the blade of that scythe had disappeared! I know how perfect utterly rusty parts come out of vinegar after 1 or more days, especially if you use a water-pressure cleaner next. But I also know that if you then just let the parts dry and sit around, it will be rusty again soon - very rusty after a few days. Hence the paint. But you cannot paint contacts. And I do not see you applying a new coating of silver onto the contacts (e.g. via electrolysis) after removing the oxidized layer. Oxidation means that part of your contacts top surfaces were converted via oxidation, and you removed that unwanted oxidized "material", i.e. at the end of the day, some of the original top surface has been removed and is missing now to protect the contacts - while at the same time I think it is unlikely that you have succeeded in removing all the vinegar and salt after your cleaning - it will still be hidden in small gaps and it will continue to "dissolve" your contacts in the time to come. So to sum it up: your contacts and fuse box may look nice in this brief present time, but it would be a very big mistake to even consider reusing this loom in the P1 EVO, as the self-destruction of this loom in the near future is pre-determined and finding a failure in an electrical system that is playing up is no fun. I just found after a very long search the reason for my ABS warning light being lit up on one of my cars, on my X-Type: It was in fact one silly pin in a huge connector to the ABS module - than pin connects a cable to one of the wheel speed sensors. Plus, that fault was an intermittent fault - the worst kind of to find. And mad failures like that (including intermittent) are pre-programmed for your P1 EVO, if you actually to reuse the old loom! Cheers, Peter

 

Peter: I think you are correct. On one of the connectors to the throttle body, (the two wire one that goes to the gear mechanism,) the locking plastic has cracked and broke off. It appeared the plug was still tight but I taped it and then put a zip tie to hold it tightly attached. The car has not gone into limp since! I would like to replace the plug but I am not seeing the plug and two pigtail wires as a small harness to splice in for sale any where. Parts Geek has several plug harnesses for sale that go to several different locations on the car but I can't tell if any might work. If you or anyone has a part number and place to get one let me know. Thanks for the pointing this out.

 

Good to hear. Yes, zip tie is the way to go with those old connectors (that's what happens to plastic in the hot environment of an engine compartment: It breaks...)
Sometimes I even apply black roofing silicone to a connector (and zip tie, or at least sticky tape, while the silicone dries out).