The fuel additive will take a day or two of driving for it to clear up any issues with fuel persentation.

As for the vibration @70 it could be a number of things from balancing the tires to bushings. Checking one wheel at a time by jack the wheel up off the ground then take a 2x4 or pipe under the tire and lift up and down and see if you have any movement then take the wheel and try to move it vertically and horizontally and see if movement takes place. If that does not yield any movement take it in to a shop that is willing to check it for you and see what they come up with.

An engine mount is easy to detect. Look at the engine mount and see if you have any evidence of a black color fluid leaking from them. If you want to check it further open the hood of the car put it in “D” and accelerate gently with your foot on the brake. As you are doing this look at your engine and see if you have any lifting of the engine. If the mount is broken you will see the engine lifting. Now remember not to do a quick or high acceleration to do not want the car to move just the engine. Also it is best to do it in the driveway or open space and do not stand in front of the car in the event it moves.

 

I would for sure swap the O2 senors while you have it jacked up. That will tell a lot.
.
.
.

 

Owning a 2003 S-Type 4.2 V8 i had codes P0171 and P0174.

Replaced the MAF and checked hoses, codes did not disappear.
Next check would have been a smoke test since most problems on these codes seem to be vacuum leak related.
Euro 95 i normally fuel my car up with btw.

However after about total 2200 miles (3500km) to Italy:

1st Fuelstop (Germany) codes became less frequent.
2st Fuelstop (Italy) codes became even less frequent and P0174 disappeared.
3st Fuelstop (Italy) only the P0171 popped up a few times.
4st Fuelstop (Italy) no more codes.
5st Fuelstop (Germany) no more codes.
6st Fuelstop (Holland) until today no codes pop up

Did hook up my ELM several times and saved the results so gonna analyze them next maintenance with my Jaguar specialist and then also gonna do a smoke test just te be sure.

In my case fuel related or was the V8 finally in his element on the German autbahnen ?

 

Check fuel trims. Stop clearing codes as they're there to warn you to fix the fault(s).

 

Today I replaced all the spark plugs with NGK Iridium plugs. All of the old plugs were very old, if not the originals, other than the spark plug and coil on cylinder 7. That had an aftermarket coil with a newer plug.

I read posts earlier saying you cant ohm through these coils. I did anyway, and they all had very similair readings other than the new coil on cylinder 7, which was reading higher risistance. A few of the plugs were very loose, and one was hand tight, but i dont see that causing a lean condition.

While i was under there I swapped the O2 sensors, and then cleared the code. I drove it a bit, but the code hasnt come back just yet.

I have found a local place that sells BG44K, however they were closed today due to labour day. So tomorrow ill go grab a can of that, and the OBDII reader should be here too.

Thanks for the help, and ill keep you updated.

 

The code has come back and its still p0171, so I can eliminate the 02 sensor.

The OBDII reader came in today, I'm just still trying to figure out the app and getting used to it.

I have put a can of BG44K in along with a full tank of gas.

I think Im going to swap all the coils from the left to the right to see if it follows and go from there.

 

See what takes place first.

Gus
www.jagrepair.com

 

Go to Advance auto or Autozone, get their code reader and check short trim (search internet)

 

After a ton of reading online, and a good amount of messing with the scan tool and app, the car is deffenitly running lean on bank 1.

I am hoping the 44K will help clean the nozzles and fix the problem. But if not ill start taking a look at the individual injectors, which did not look fun to change. (Im assuming the superchager needs to come off first.)

As for the vibration, its deffentitly coming from the front right. At higher speeds it gets very noticable, and much easier to diagnose. All four tires are getting replaced monday along with an alignment. While I was under there i found both tire rod end bearings completly shot, and i have both of them on order and will be swapping them out next week also, (before the alignment). If it continues after that ill try the wheel bearing, the brakes seemed fine, and in all honesty the wheel bearing seemed fine also with the car on jacks.

 

More likely an air leak - did you check? (post #24)

 

I did look for leaks, and cant find anything, at least anything obvious. Where are the common places they leak? There a bunch of guides, but i couldnt find anything for this engine, they all seemed to be for the V6.

 

The advice in so many many threads is to watch the trims and use a burnable gas (like propane).

The freeze frame data gives big clues as to when the condition occurs.

And before doing any of this you do what the threads say and rev...

 

Heh heh heh, bet you wish I had a V8....

 

It's probably long past the time when you should've swapped to one...

 

I had a P0171 without a P0174. I found the catalytic down pipe to the exhaust manifold flange loose - probably left that way by someone working on it previously. I tightened it up and the code went away.

 

Spark plugs last almost forever. You have platinum plugs, they don't wear out.

 

And what did we find on this?

Gus
www.jagrepair.com

 

Just wanted to give an update on the car.

After checking everything, and the help of Gus, I traced the problem down to the cylinder #7 injector.

I purchased the injector and over the course of three days, probably 10-12 actual hours of work and half a dozen trips to the auto parts store, I pulled the supercharger, and changed the injector. While I was there I swapped all of bank 1 injectors to bank 2 and vise versa just to verify for troubleshooting purposes, and changed the fluid in the supercharger. Im kicking myself for not changing the coolant line under the supercharger while I was under there, but I was under time constraints and just wanted to get everything done. Its definitely not a job I want to have to do again!

Throughout the process I found multiple things wrong and corrected them while I went to include a torn seal between the intake manifold and throttle body that was duct taped together. (Before anyone says that was the problem, I fixed that prior to pulling the supercharger and the code came back) I also found that the knock sensor had gone bad at one point and the previous owner just installed it on the strut tower! I originally knew it didn't belong there, but didn't know what it was until I got the supercharger off where both were clearly visible.

After the install, between work and my days off, I traced vacuum leak after vacuum leak seeing how a lot of the vacuum lines broke during removal, literally crumbling under hand pressure, they were just old and brittle.

Amongst all of this, I started to have transmission problems, I became too frustrated with the car that I too a good 2-3 week break without touching it, and drove my second car in the mean time. I found the transmission to be serviced improperly and with the wrong fluid. Luckily just servicing the transmission with the correct fluid and changing out the filter/pan solved the problem, and in-between that randomly a coil decided to take a ****.

It has been a very long process, but I am happy to say that after the past week of constant driving the transmission is running flawlessly, and I have not gotten a CEL. I finally got the computer to reset allowing me to get a inspection sticker tomorrow morning.

With a lot of work, and patience, I am happy to say the car is running good, and it feels good knowing I did all the work myself (I almost gave in at one point!), but I have learned a ton about the car, and am confident I could have that supercharger off and back on in half of my original time.

I appreciate all the help, especially from Gus, who took the time to give me a hand in troubleshooting over the phone!

 

A horror story with a happy ending!

 

Great job and similar to what I went thru. Always glad to hear the details as it will help others.

Did you replace the vacuum elbow to the power brakes? That factory O-ring is hard as a rock by now. You must have since no lean codes.
.
.
.