I am starting a new thread so I can group everything together. My problem is that I have restricted performance and I can tell the car is gulping down the gas. I have been battling several issues over the past two years and I have not been able to get rid of the rich codes.

These are the things I have done:

-replaced all spark plugs
-replaced all coils
-replaced air filter
-replaced all four O2 sensors
-replaced fuel filter
-replaced the MAF sensor
-replaced water pump
-replaced gas cap
-replaced heater valve
-replaced climate control module
And most recently:
-replaced the catalytic converters (purchased from Rock Auto)

Now I am getting the codes:

P0172
P0175
P0400

Any help is appreciated.

2005 Jaguar S-Type R

 

PO172
System too rich, bank 1
Possible cause
Intake blocked, EVAP cannister purge valve, fuel pressure, EGR system, injector(s), H02S.

PO175
System too rich, Bank 2
Possible cause
As above

PO400
Exhaust gas recirculation (EGR) system - flow malfunction
Possible cause
Hose Leak/Blockage, basic setting not carried out (if applicable), wiring, EGR valve, EGR solenoid, ECM.I have taken the above from the Autodata system I use.
I may be wrong in this, but I'm sure the later spec'd 4.2's used a P1 prefix and not the P0 prefix.
In other words, where you are showing the code P0172, the later would show P1172.
But like I said, I could be wrong, so please don't shoot me.

 

What stevep10 said, plus look into investigating fuel pressure regulator and getting injectors cleaned (start with seafoam into air intake, escalate to ultrasonic cleaning and/or replacement).

 

There is no fuel pressure regulator as such. The S-Type uses a 'return-less system'.
Monitor STFT and LTFT and you will likely see negative numbers as the ECM is trying to 'lean-trim' the mixture.

Throwing parts at the problem can get expensive.

Could just be high fuel pressure from a faulty sensor but???????

bob

 

What codes did you have before all the part changes?

 

As far as I know that is NOT the case. It would break USA laws (also EU & UK ones). Jaguar once got fined for something much less serious and I cannot imagine theyd' do something so terrible. (They are not VW.)

 

On the actual problem... something like an elm327 and watch live data.

Watch fuel trims - see the vast number of threads about these!

Check fuel pressure and also use a physical gauge to see if plausible.

Check every other sensor/value whose meaning you can figure out (probably only a few) for plausibility.

Total cost almost nothing but quite a bit of time.

 

Thanks for the info! I need an autodata system. My car definitely uses the P0 coding.

 

Thanks! I'll check out the seafoam and see where that goes.

 

No doubt on the cost of parts. I'm hoping that I am finished buying parts for a while! Checking the fuel pressure may be my next plan of attack. Thanks!

 

Before I put the new cats on it I was getting the two rich codes and the P0400 appeared and went away on its own. I had the cats checked out and was told that they were borderline bad so I replaced them hoping that would solve the rich codes. Unfortunately after the replacement I now have the rich codes AND the P0400 code.

Prior to that I had several other codes that were fixed with the part changes. I can't remember the codes off hand. So far nothing has cleared up the rich codes, ugh.

 

Thanks!! This sounds like a good plan of attack. I especially like the low cost option...

 

Please avoid all such products. They are of no benefit. Jag specifically warns against them in the owners manual.

There is no history of faulty fuel injectors on S-types nor any history of miracle in a can snake oil fixes that actually work.

Seafoam works great for it's original purpose (unclogging tiny 2 stroke outboard motor carbs) but has no business in modern cars.

 

Thanks for the heads up!!!

 

There are reports of contaminated injectors but it was years ago. See the related TSBs about using chemicals to clean injectors.

bob

 

Thanks!!!

 

You have a vacuum leak. The P/B vacuum elbow is almost guaranteed to be leaking at this late date. All STR's have the same problem.

Get your ELM327 and set up monitoring your fuel trims. The P/B connection is on the passenger side on the intake elbow for the super charger. NOT real easy to get to. With the engine cover off you can get to it if you know where to look.

Spray carb cleaner on this connection while monitoring the fuel trims. You will know quickly the results.

Also check the plastic intake tubing and noise canceling chambers. The plastic gets old and you could have a hole somewhere.

These are not the only vacuum leak points but are well worth checking.
.
.
.

 

Thanks! I will buy some carb cleaner on the way home tonight to try this!

 

Careful with the carb spray. Avoid PAINTED parts as the solvent can dissolve the paint.
A small propane torch (UNLIT) can be used near painted parts without damage.

Carb spray has better AIM into deep/distant areas.

bob

 

Thanks!!