I had both of my fuel pumps replaced a few weeks ago at All Jaguar in Longwood, FL. I drove the car the one hour back to my home, it ran great and I parked it for the next few days.

A week later, I took it out an filled the tank, as I drove away I could sense a faint smell of gasoline. About 30 minutes into the drive I got an on and off again Restricted Performance message.

Took her home and had a mechanic buddy come by and pull the codes - no codes at all. ??

That was about 3 weeks ago. I have been driving on the same tank of gas (I only drive this car once a week or so) with no problems, no gas smell and have not filled her up again yet.

Filled it up last night and the same thing happened, RP on/off. When I got it home the RP was not showing.

Chris with All Jaguar had called to follow up with me on the problem a few days ago and suggested that I go ahead and fill it up again and see what happened.

When I emailed him last night, he asked me to pull the codes, which I will try to do in the next few days, but if it is like the last time there won't be any codes stored, we'll see.

Any ideas what could cause this to happen? I am thinking that something in the evap system is not hooked up right or malfunctioning, but it should throw a code, right?
Vector

 

Being that it did it after getting gas my bet is o2 sensor going out. Same was happening to me.

 

Thanks for the suggestion, but how would an O2 sensor on the exhaust system know whether the tank was full or not?
Vector

 

I am betting the gas smell is just lingering from the fuel tank work.

Try to pull the codes when you are in resticted performance.

 

All i know is that I coudl refuel and then my car wouldn't even want to start...i had gotten to where i'd just leave it running while refueling...then the o2 sensor started getting worse...restricted performance after every refuel...rough idle started getting worse then finally horrible mileage, codes and transmission issues...changed the driver side upstream sensor, reset computer and all was well again.

 

Had a friend of mine who is a mechanic bring his code reader over.

When we first hooked it up we got P1111 - all OK?

I took it for a run and the first set I got was P0301, O0302, P0303, P0304, P0305, P0306, P0307, P0308 - Misfires on all cylinders?

I cleared that set of codes and then I got-
P0300 - Random Misfire?
P1000 OBD Readiness Test not complete?
P1316 Misfire rate exceeds emissions?

Cleared that and got the same set of codes again.

I could not get it to go into restricted performance mode tonight.

Should I throw a set of plugs in her and try again????
Vector

 

Hold off on the plugs. If you have a misfire problem you should be able to hear it. There is something else going on, but I am not going to try to second guess the problem. People like Whitexkr, Brutal, and others are much more qualified.

P1000 is okay, just means systems check cycle not complete, will become P1111 after a few starts.

 

Can't really "hear" any misfire from the engine, seems like it is running very smooth.

I took her out for another run tonight and finally got a "restricted performance" indicator light and message.

Pulled the following codes-
P0333 - Knock sensor 2 circuit high output bank 2?
P1000 OBD Readiness Test not complete? (I know what this is)

Cleared that and then got-
P0300 - Random Misfire?
P0333 - Knock sensor 2 circuit high output bank 2?
P1000 OBD Readiness Test not complete? (I know)
P1316 Misfire rate exceeds emissions?

The "restricted performance" indicator was going on and off while I was driving, just like before.

I bought some NGK BXR6E1X-11 iridium plugs just in case.
Vector

 

I suggest checking your fuel pressure, given that the fuel system was just worked on and the misfire affects all cylinders.

 

I did some searching.......

Looks like I may have a bad knock sensor on the left side.

I see that I have to remove the supercharger to get to it, right?

Oh my, this could take a while.

I should probably replace both sensors while I'm in there and probably all the hoses under the supercharger too.
Vector

 

Got a fuel pressure specification for me?
Vector

 

It should pressurize at the fuel rail to 43 PSI when you turn on the ignition without starting the engine.

 

if its telling you the knock sensor i'd change it as its putting it up for there for a reason...and yup i'd do all the hoses underneath while you are there.

 

Fuel pressure was fine at 43 psi.

Here we go..........................

If you need to know where the fuel schrader valve is for a 4.0 SC, it is right in front of the left bank under the wiring for the knock sensor. It took me some time to find it.
Vector

 

Brutal, who is one of the most respected techs on the forum posted this in the S-type forum today:

"Coils on the cylinders that show misfires and random misfires is normally from fueling issues like dirty injectors and/or winter blend fuel/ethanol. We have alot of issues here in houston with warm spells in the winter when winter blends are at the gas stations, even no starts."

Perhaps a fresh tank of gas might be in order before you dig too much deeper.

 

So when you guys get crap fuel down there, would adding a fuel additive, such as octane boost etc be helpfull ?

there must be some way to get around **** fuel....

Thanks
Gerry

 

Short of removing the fuel injectors for cleaning (which is a significant job on a supercharged engine) I think a can of BG-44K added to a fresh tank of gas from a different gas station would not be a bad idea.

 

It might be worth pulling a few plugs to see if they are oil covered. There have been posts about leaking seals around the spark plugs causing misfires.

 

Ever try to siphon gas out of an XJ? It doesn't work very well......lol.

I am going to put in new plugs and fresh tank of fuel with injector cleaner and see what that does.

This all started when I fueled up in my small town, they don't sell much premium gas here and I usually go to the interstate to get fuel because I think it is sold more often there and might be fresher.

It may just be some bad gas, but I have a full tank of it, gotta run it out, I guess.
Vector

 

best way to drain your gas tank in the xj8 is to remove the line going into the fuel filter, put a hose on the end and run it to gas cans, open the gas lid, remove the gas cap...gas will empty into cans... :-) Then add new gas and see if it was bad gas. Change fuel filter since you've already unhooked the line too.