So my Jag died on me going doen the freeway the other day. I had it towed to a shop where they diganosed it as a crank position sensor. No big deal, they replaced it and now they are telling me that I also need a new fuel pump. They say that at idle, it runs, but when they try and move the car it dies and that must be bad.

It seems to me that if the pump is making pressure at idle, then it should be ok, or is it possible that the pump can make pressure at idle, but can't keep up with fuel demands at anything other than idle? I am hoping one of you jag experts can help me out on this one.

 

It sounds possible but unlikely - why would two unconnected things both fail at the same time?

But if it won't run.... why not has to be figured out!

 

Were there any engine codes thrown? The crank sensor should have given off an OBD2 code. Don't know about the fuel pump. I doubt that pump failure gives off a code.

 

Hey TX, is it too far to idle on over to Brutal's? Pretty sure bet he could fix you up!

If I DID buy their fuel-starvation theory, I'd be more inclined to change the $8 filter before I tackled the pump. But I'm throwing in with John....not b'lieving they've corrected the cause of the stall yet, despite they got it lit up. This shop have a real, live Jag module-reader? You said they report "when they try to move it" it dies....so can they rev it ok in idle/park and only when they shift into D or R? or does it die anytime it comes off-idle?

oops! just noticed you have a 5-speed...didn't even realize the N. American mkt got manual trans in S-types.....was initially "thinking-out-loud" that the electronic xmsn may be messing with the powerplant somehow...but I ammend my question: "does it come off-idle at all and only die under load?" or does any blip of the throttle whatsoever kill it?"

 

It looks like I need to get more details Tom the shop. They have a live monitor to watch the engine and that is how they found the CPS. It is a bit far from where I am to the jag dealer maybe they left the parking brake on and stalled the car? I will call the shop and get more details. Thanks so far guys.

 

Wait.... after replacing the bad sensor did they clear the KAM (keep alive memory)? It stores what the car has learned and may be junk due to the bad sensor.

Cheap but risky way to do it is disconnect battery BUT proper OBD tools will do it without the risks attached to batt disconnect (briefly, that car fails to set all monitors so then fails to flag any codes yet is faulty).

After clearing KAM, watch OBD status to check both banks got CL (closed loop) within (say) 2 mins.

 

I don't know if they cleared the computer, but I would think it would fire up fine in open loop until the engine warmed up. I will ask them anyways, I just really don't want it to be the fuel pump, and since it is building pressure, I can't imagine it being bad, but maybe I am wrong on this.

 

In case it's got the EPB then you can't accidentally leave it on
It auto-releases.

 

Actually with the manual the EPB doesn't release on its own, and it sets any time you turn the ignition off. When I first got the car I was going to show my wife how cool it is that the EPB will hold the car on a hill, and I stalled it out to a nice round of laughter.

 

alright the shop says it is just running really bad and it is not building fuel pressure to spec, but tey couldn't tell me what it was building too.....

 

It auto-sets on the auto when you take the ignition key out (unless you hold the EPB paddle down). It auto-releases when you put the car in D and give it gas.

Does it not auto-release on the manual when you put the car in gear, lift the clutch and give it gas?

Not that I want a manual (no way!) but not auto-releasing would really be a negative for me.