So about 2 days ago my car definitely started feel like it lost a significant amount of power and the check engine light came on. after taking my car to AutoZone and getting the computer Scan they gave me a list of about 7 codes that I was wondering if anybody had any insight on what they might be and how I could fix it.
p0456
P0174
P2406
P0088
P0087
P0128
P0305
P0101

 

Download a free copy of the X150 service manual for you engine to find out what the codes mean.

In the meantime unhook your battery and charge it fully overnight. Then once powered back up drive it until it codes and see what new codes pop up.

report back with the new codes.

 

Or Google them. Most 4-digit codes are the same among vehicle makes.

https://www.google.com/search?q=p045...nt=firefox-b-1

 

The problem with Google is what the code means for a Hyundai might not be the same for a Jaguar. Chased my tail going that route in the beginning. Again, find a copy of the service manual and read it.

 

p0456 - Evap System Leak
P0174 - System Lean Bank 2
P2406 - Evap Leak Pump Sense Circuit High
P0088 - Fuel Rail Pressure Too High
P0087 - Fuel Rail Pressure Too Low (???)
P0128 - Coolant Temp Below Temp
P0305 - Cylinder 5 Misfire
P0101 - Mass Air Flow Circuit Malfunction

All Jaguar Codes. All from Google.

MOST referenced 'jaguarforums dot com'

I know what your saying though... just cuz 'same code' does not mean 'same problem'.

 

What's the voltage of your battery ?

These cars are notorious for spitting codes out when the battery is faulty

 

The advantage of the Workshop Manual decoder is the additional accurate information on possible causes. For example, P0456:




The 00 indicates there are no extended codes for this DTC.

Probably the greatest source of misinformation resolved across our Model forums are DTC decodes from generic OnLine lookups.

Earlier models in the JTIS days had separate DTC lists published by Jaguar which made lookup very easy. The XK era models have the DTC's integrated with the Workshop Manual texts and therefore require a search. It would be a great contribution if anyone was prepared to extract the DTC's from the Wokshop Manual and compile into a table. It it's a bad Winter, I may give this some further thought!

Graham

 

A bit more info on P0456 from the AJ133 EMS OBD diagnostic manual:

5.3.2 Description The evaporative monitoring system being used permits the detection of leaks with a diameter of 0.5 mm (20 thou of an inch) or greater.

This is achieved by means of a pressure test of the system. This is performed by the Diagnostic Module - Tank Leakage (DMTL), which is an electrically operated pump fitted to the atmospheric air intake of the charcoal canister.

The test proceeds in 2 stages:

Reference Leak Measurement - The pump operates against the reference restriction within the DMTL. The Engine Control Module measures the current consumption of the pump motor during this phase.

Leak Measurement - The solenoid in the DMTL is operated in order to shut off normal purge air flow into the charcoal canister. The pump can now pressurise the fuel tank and vapour handling system. The Engine Control Module again measures the current consumed by the pump motor and by comparing this with the reference current, determines if a leak is present or not. A high current indicates a tight system and a low current indicates a leaking system.

Fault Conditions That Can Be Identified:
Rough leak (1.0 mm >) - P0442
Small leak (0.5 mm >) - P0456
Reference current high - P2406
Reference current low - P2405
COV stuck open - P2450
COV stuck closed - P2451
Reference leak check too long - P2404
Noise fault - P2404
Pump electrical high - P2402
Pump electrical low - P2401
COV electrical high - P0448
COV electrical low - P0447
Pump heater open circuit - P240A
Pump heater low - P240B
Pump heater high - P240C