I bought the Autel MP808 and got a bunch of error codes. The relevant ones were P0171, P0174 which said both banks were running lean which suggested why it went into restricted performance when pushing the car. I presume it kept enriching the mixture thinking it was running lean, until it exceeded the specs, thus triggering the Restricted Performance (amber) message. Surprisingly, it still got 9.6 l/100 (24.5 MPG US) on the motor tour.

Rather than spend time under the hood, I booked a pressure test at E&H Motors in Pukekohe, a place that specialises in performance tuning and advertised a $55 smoke test. In about ten seconds they found the PCV hose had popped off completely - oops, how did I miss that one? Anyway, they did the pressure test and found no other leaks so I bought peace of mind. I cleared the codes, took it for a drive, no errors (except P1582 "Flight recorder data is stored" which is not an error, but a notice... why it does not clear is a mystery since all the other DTC codes are gone).

The first time I ran the scan on 22 Jan I got 18 errors. I cleared them and on 31 Jan got 9 errors. Back up to 16 errors on the same day.

ECM (Engine Control Modules) 5 faults
TCM (Transmission Control Module 1 fault
ABS (Anti-lock brakes) 2 faults
IP (Instrument Pack) 1 fault
EPB (Electronic Parking brake) 1 fault
ASU (Air suspension module) 2 faults
ATC (Climate Control Module) 2 faults
DSM (Driver's Seat Module) 2 faults

DTCs were

01. ECM P0171 System too lean on bank 1
02. ECM P0174 System too lean on bank 2
03. ECM P1642 CAN link circuit malfunction
04. ECM P1260 Security Input
05. ECM P1582 (Flight Recorder data is stored (the same error that survived)
06. TCM P1797 CAN transmission control module to engine control module malfunction
07. ABS U2523 CAN message timeout from the engine control module
08. ABS B2141 Control module configuration failure
09. IP U2523 CAN message timeout from the engine control module
10. EPB U1027 SCP (J1850) invalid or missing data for engine RPM
11. ASU U2523 CAN message timeout from the engine control module
12. ASU U2518 Rear climate control module missing CAN messaging is missing
13. ATC U2516 Air Suspension module bus off
14. ATC U2523 CAN message timeout from the engine control module
15. DSM B1940 Seat memory position out of range
16. DSM B2309 Seat motor out of range

I cleared these today after the pressure test and none came back but the P1582.

Some may be related to the hose off. Other items not yet addressed include the yellow air bag light coming on from time to time, then going off, and the front air shocks drop in 2 days, but pump up in 20 seconds before driving. The prior owner replaced one of the shocks, but that did not solve it and he could not find the leak.


BELOW: The offending hose, reconnected

 

I get RP during a cold start. For some time, got only the yellow light. Now both yellow and red are on. Idle is super rough! Suggests appreciated. Thanks

 

I see you live in Sacramento California.

Choose the nearest O'Reilly Auto Parts store in Sacramento (there are 14 - see link). As them to hook their OBD reader to your Jag (google where to find it... hint under the dash above the footwell - I can tell you where it is on a RHD XJ6, which may be different than your car). It's free (read this Link). This will give you error codes.

Think of your Jag as a mobile computer. It has sensors throughout. The RP is to protect the car. The rough idle is probably why but you don't know why it is running rough. The OBD computer in your Jag should tell you. If there are a bunch of error codes, ask the store rep to clear all of them (after you take a photo of them), drive around the block and hook the OBD reader up again. If nothing comes back, take the car home, park it overnight, then drive back to O'Reilly and hook it up again. Odds are the errors will be there.

Note that in addition to generic error codes, Jag has some unique to them. The ultimate way to get all the data is either a Jag dealer or a Jag independent shop that has all the Jag codes.

At that point you can

1. ask O'Reilly for their opinion
2. Visually inspect the car. Follow the tips in this thread. (In my case, I had a filthy MAF sensor, but when that did not cure it, we found it had a hose that had popped off and was adding fresh air downstream of the MAF sensor which confused the computer system)
3. Get on your computer at home and go a Google search on X350 and the error code and start learning.
4. Post the error codes to this forum thread to see if anyone had a similar problem and fixed it.
5. Find an independent Jag shop - see this link that lists them and pay them to track it down and fix it.

Do remember that automotive computer systems have an expectation set. When something exceeds that, the computer attempts to adjust, but if something is wrong... like a filthy MAF sensor or a hose popped off, it may do the wrong thing until the specs exceed the programmed min/max that triggers RP, and amber/red lights. Like the fuel injection system enriching the fuel-to-air ratio when it should be making it lean (or vice versa) because air is entering downstream of the MAF sensor.

When you get an amber warning light, don't wait until it turns red. The longer you delay the more damage that could be happening.

When you do get the OBD codes and have fixed it, please post details (and photos) for future owners with the same symptoms.

 

Hi CA Jag,

Welcome to the Jaguar forums! It's great to have you with us.

The yellow and red lights and rough running suggest you have one or more cylinders misfiring, and the lights and Restricted Performance are warning you to not run the engine until the misfires have been resolved. If you continue to run the engine, one or both catalytic converters may be ruined, valves may be burned, or other engine damage may occur.

As x350 recommended, you need to have the car scanned for diagnostic trouble codes (DTCs), but you really should not drive the car in its current condition.

An inexpensive setup for scanning codes yourself is an ELM327 OBDII adapter and an app for your phone. If you use an Android, you need a Bluetooth ELM327 and the Torque Pro app. If you use an iPhone, you need a WiFi ELM327 and the DashCommand app. With one of these setups, you can scan and clear powertrain-related codes (P-prefix), monitor Live Data, and perform other actions.

If you can't wait for an ELM327 to arrive in the mail, Harbor Freight Tools sells inexpensive OBDII scanners. But please do not drive your car while it is misfiring or more serious damage will occur.

Cheers,

Don

 

Thanks for the help. All of it makes complete sense. My BIG problem is that the car isn't drivable. Still starts instantly and sounds good but after a couple of minutes RP/yellow/red kicks in. The other BIG problem is that I can't pull codes.

1. I have an Innova 3100 reader. Powers up. Says "Read". No codes. Other JagForum members mention using it. Works perfectly in my other cars. Also borrowed my neighbor's basic to test. Powers up. Says "Scanning". No codes.
Checked (w/ DVOM) 2 OBD port specific fuses. OK. When I get the car running, plan to buy an expensive reader to get real time, Jag specific codes, etc.
2. Nothing obvious visually but I need to learn the car. Engine compartment is clean, hoses and lines look good.
3. Good advice. Plan to learn the codes.
4. Will post.
5. Completely agree! That was the game plan. British Car Services my first choice but he's booking 2 months out. Have an appointment. Wish I could drive. He'll do an SDD anytime but can't keep the car overnight. At this point, getting codes is the first step. Maybe I can make it drivable. At least I can talk to other Jag garages w/ a list of codes and see when someone can get to it.

Thanks for computer system details. This seems to be a progressive failure. Car ran smoothly for 15 minutes then RP/Yellow. Ran smoothly several times for 5 min then RP/Yellow. Still starts instantly, sounds good and runs smoothly for 1-2 but now RP/Yellow/Red. Haven't started it since red showed. Idle is horrible and It's an interference engine. Fix may be simple (MAF or O2's for example) or difficult (long list). Last time, still started smoothly and rev's came down. Without codes, I can only guess. Have a high quality battery that charges to 13.5. Holds that if disconnected. Drops to 12.5 (or lower) overnight which is a problem. Failed module? Short? It's a CA car. Super clean, no rust, always garaged. Seller always used Chevron.

I will post info and pictures on everything. Hope I can help other owners. Thanks again.

 

Probably the most common cause of your symptoms is a failing ignition coil. The original coils were made by Denso but those are hard to come by today. Other brands known to work are Airtex (the ones dealers sell in Jaguar boxes), Delphi and NTK. If the car has more than 60K miles, it's probably also time for new spark plugs.

Cheers,

Don

 

Thanks. Def a possible cause. Thanks for the brand recommends. Seller claimed new plugs and wires but nothing on the coils. Car has 75k miles.

 

This is useful for any British car owner in the Sacramento CA (and surrounding area). Thanks for the list of possible garages. One possible is Stewart's European Auto Specialists (focus is Jaguar and Land Rover). General Mgr took the time to answer all my questions. They're scheduling a week out. They work on these cars all the time. First step is to solve the "can't pull codes" problem. They also work on Ferrari, Porsche etc so will be expensive. British Car Services is booked two months out. They recommended I do a compression test to see if chain timing chain(s) has skipped a tooth. Got better advice from Stewart's. To start, solve the OBD access problem and they can figure that from codes.

 

Good suggest. Stewart's European Auto found the problem in less than an hour. Had no problem pulling codes (I couldn't). The restricted performance/horrible idle is related to problems w/ the ABS. They disconnected and car actually idles smoothly. They're having it rebuilt from a reliable vendor for about why I'd pay (400). Estimated time is 7-10 days. In the meantime, they're storing the car indoors. European worked on 3 XK8's last month. Also has access to parts cars as an option. So far, so good!

 

Hi CA Jag,

You could help us understand what is wrong with your car and what is being repaired by posting the codes that Stewart's European Auto pulled from your car. I understand how certain ABS problems can trigger Restricted Performance, but I'm scratching my head wondering how an ABS issue could cause the idle to be horrible...? Could that have been due to a leak in the brake booster vacuum pipe?

Cheers,

Don

 

Thanks for your feedback. I'm wondering too. I'm going to drive over and ask for codes. Also ask that they start it. The general manager did say the car runs normally when ABS disconnected. Maybe they fixed something else to make it possible? Good thought on the brake booster pipe. It's interesting that they had no problem pulling codes w/ Jag diagnostics. I tried w/ several good quality readers. No luck.

At least the tensioners don't seem to failing yet. No chain slap or noise at idle. Yes, need to be replaced very soon but I may be able to drive the car a few miles to see what I've got. Fire sale price. Many compliments on how attractive the car is (sound familiar?). We'll see how it plays out.

 

Hi Don

Have the codes. C1095 (ABS Hydraulic Pump). P0300 (Multiple random misfires?), P0305 (Cylinder #5 misfire?), P0308 (Cylinder #8 misfire?). Looks like replacing the ABS module could solve the ABS/traction warning message. I can't see how it relates to the obvious misfire problems. Seller says wires and plugs are recent. Need to check. Testing coils is the next step. Headed to the garage tmrw. Be interesting to see if/how the car runs. He did say it ran normally. Unless they did something else (like the hose, other vacuum or minor electrical), doesn't make sense. Garage has a great rep (also super clean) and deals w/ Jag, Land Rover and very high end cars. I don't think they're billing for unneeded work. Also total cost for diagnostic, ABS remove/rebuild/reinstall is less than dealer quote (800) to just do the diagnostic.

I've started the car several times over the past 2 weeks. Car always starts instantly. Has a fast idle but smooth. Initially could drive the car around the block. ABS/RP/yellow on. After that, less and less time until it goes rough. Now ABS/RP/yellow/red. Car still starts instantly. Still fast idle (cold start) and smooth. As the idle starts to slow down, the rough idle suddenly starts. Why aren't the misfires always happening?

Jim

 

email from the garage.....The C1095 is a hydraulic pump motor fault for the ABS which is thrown when the control module craps out. Engine ran smoothly with ABS module disconnected,

 

Hi Jim,

I'm not sure you've ever told us the year and model of your Jaguar. It is helpful if you go to your User Control Panel and edit your signature to include the year, model and engine of your Jag so this info shows up in all of your posts.

On X308s, late X100s and earlier cars, the C1095 code is typically caused by cracked solder joints on the ABS Module circuit board at the connector pins for the ABS pump. Reflowing and supplementing the solder at these joints (and others on the circuit board) is usually a permanent fix. I assume the same may be true on the X350s, so that is probably what the shop is having done. The motors rarely fail.

But I cannot think of any cause-and-effect relationship between the ABS Module and cylinder 5 and 8 misfires. Ignition coils are a common failure point. You have misfires in both banks. Were there any diagnostic trouble codes related to lean running? Air and vacuum leaks are very common on the X350 and can cause misfires.

BTW, unless your Jag is an XJ40 or XJS, it doesn't have spark plug wires. It has individual on-plug-coils.

Cheers!

Don

 

Misfire sound like small vacuum leak. Small enough not to affect higher rpm but large enough to run too lean at idle. Fuel trims should point to that. STFT should be high at idle and drop as RPM increases.
ABS must still be at least partly functional. It supplies the keep alive signal - vehicle speed - to the ECM which transfers it to Instrument panel which then broadcasts it to every other module. Even the radio is not totally happy when that signal is lost. Modules go into default mode at that point until vehicle speed is returned.