Hay everyone hope all having a good day. I have posted on a good few forums but never had luck. I'm new to this one.
Right the car is a xtype 2.1 v6 53 plate sport. 86k on clock never had a problem full service history. Theses problems started after I had to jump start a friends old vectra deisle (sorry about spelling) the night prior. Next day went to see the in-laws car ran fine up there 50 miles mixed driving with low fuel got there on way home refuels car at she'll in Fraserburgh and about 15 miles down the road went to overtake a jeep and car just splutterd at 4500k so abandons that as we were driving problem got worse and 5 miles from home the max revs I could get was 1500 with little throttle. But only when under load.
Hear is the original problem I posted on anothe forum
Hi all my jag has taken ill. All happens after refuel in shell. When cold everything is fine but when up to tempruture and after about 10 minutes at operating tempruture the car will not take more than 25% to 50% to WOT with out bogging spluttering and the it's almost like to much fuel and a missfire but it reminds me of my bike that would to the same thing with to much air car will just slow rpm and speed right Down to almost a stall. But if when driving you shut the ignition off then restart the car il will take all throttle inputs and WOT but it will get to about 4000 rpm and just won't go past in any gear then it will start to take less and less throttle to bog and the max rpm slowly drops to 2500 but in neutral rolling or sitting will rev upto the limiter no problem and car starts really easy all the time. Although it dose not lock all the time with the fob There are no codes apart from P1000 This only happens when hot.

I posted this as a reply as I thought the problem was sorted turned out not I will copy and paste.

I have checked all fuses replaced all sensors on engin and vvt solenoid and manifold tuning thingys fuel pump plugs coils oil and fuel filter everything makes an emprovment but the problem still comes back. I plugged into a mates MOT PRO eu908 scanner and it pulled some codes that my laptop couldn't now some may be codes from what I have done when doing the wheel bareings but the problem was well before I did them. car car then went for mot passed its mot fine. Compression test all six pots are 145 -150 psi.
Hear are the codes that were pulled from the eu908 scanner
B1676
B1262
B1263
B1239
B2141
U1900
B1681
U2510
U2511
P1260
P1582
P1629
Some data
TPS track 1 0.80V
Vvt duty cycle 9.30%-9%
Mass air flow 0.01lbs
Mass air flow ground 0.00V
Mass air flow meter 1.37V
MAP 6.2 psi
All at operating temp

Theas are some extras from almost at temp to full temp
Not at temp yet in open loop mode
Calculated engine load 21.961%
STFT bank 1 0%
LTFT bank 1 -7.031%
STFT bank 2 0%
LTFT bank 2 -3.906
Timing advance relative to no.1 cyl 2 degrees
AIT 31 degrees C
Takes 7 seconds to scan threw every all on my kit took 3 scans then car went into closed loop the only thing that changed when in open loop is that STFT bank 2 went to +1.563

Now data at temp in closed loop mode
Calculated engine load 20%
STFT bank 1 0.781
LTFT bank 1 -7.031
STFT bank 2 0.781
LTFT bank 2 -3.906
Timing advance relative to no.1 cyl 2.500 degrees
AIT 29 degrees C

Now some other info.
o2s1_wr_lambda(1) equivalent ratio current 1.066 , -0.195

o2s5_wr_lambda(1) equivalent ratio current 1.057 , -0.681.

Now the codes I got from the eu908 I cleared as on saterday I had to go to Aberdeen for a family gathering. The car was back to normal if not better so 50 miles there with some fast and slow mixied driving the car was fine. But 6 hours later I get in to come home and just as I leave Aberdeen and put my foot down the problem came back normally takes 1 hour to get home took me 3 as I kept having to stop shut car off restart and would run fine for about 2 miles then same again.

I don't know if there are any codes as my mate is away for the week and has his scanned but my laptop says they're are no codes but it said that last time so waiting for friend to get home. I did dry my ecu out as it was under water and cleaned all earthes under Bonet. Car has not been flooded just the ecu with the bad wether but as said when I cleared the codes the problem went away to come back though. The problem happens every time though..
The o2 sensors have not been replaced. the car pops threw air box only at idle and if you put load on I.E turning the steering wheel slowly. Not driving But not any time else. Also when driving some times when you let of throttle it has a knack sound or slight pop in the engine bay but again only under load. All these problems are only under load. But won't do it when engine cold or warming up.
Hope you guys can help me out please

 

The fact it will rev up in neutral and not under load is a classic symptom of fuel starvation, most engines will rev freely on a small amount of fuel, but as soon as you load the engine the flow rate required rises rapidly. I have experienced this on both petrol and diesels in my 37 yrs in the workshop. I would get the fuel pressure checked to see if it falls off under load.
I had these exact symptons on a Golf GTI and it lost power after driving a while, and switching it off and on cleared the fault for a few miles until it did it again, I got quite good at switching it off and on while at 80mph on the motorway to save stopping!
I eventually found the fault was a tiny conical filter in the fuel line just before it entered the fuel metering rail on the engine, it was full of fine fibres from the main filter under the car and under pressure it was collapsing in and choking the flow, switching the engine off killed the pump pressure allowing the filter spring back to its normal position. I replaced it and it was as good as new, I don't know if our X types have anything like that fitted but I'd definitely get the fuel pressure checked before going and deeper. Connecting to a decent 4 gas analyser and revving under load would also give a good indication of what is happening during combustion.
If it checks out then I think your lack of fuel must be caused by a sensor or electrical problem affecting the amount of fuel being delivered.

 

Id replace the fuel filter (again?) and see what happens

 

Hi I have had the whole fuel system on and cleaned. She takes longer to develope problem if running on 99 octane. But hears one for you guys I unplugged the front bank bank 2s lambda upstream left downstream pluged in and car ran perfect up to the in laws not a problem. But when coming home I unplugged the rear bank aswell before leavening now it's a 50 mile drive home car was fine but felt a little bit hesitant but about 2 miles from home the problem started to come back. So I'm going to plug rear bank back in and see with just front bank unplugged she runs fine again. But also I pluged car into laptop and new bit of info engine not running live data showed the throttle percentage at 0.374% it used to show 0.000%

 

Hook all the 02 sensors back up and try disconnecting the MAF sensor, unplug it.
My car suffered the same symptoms, tried to stall on heavy acceleration, hated big hills. Car ran good once I disconnected it, eventually super cleaned the MAF, reconnected and problem never reappeared.

 

Thank you for that info. I'll try that tomorrow. I have fitted a maf and made a little difference but no I'll try that tomorrow. Did you're car run perfect when cold just as it was at operating temp and then longer you drove the badder it got. Thank you though I appreciate all help. Will post tomorrow results

 

Yes, at start it was fine and then the problem would get worse while driving.

 

Well tested the car yesterday and car was a lot better than having one lambda unplugged. I have super cleaned the maf just to test today. Hoap it works. oh did your X go into limp mode aswell.

 

It never did it, but I got various lights on the dash that may have been that.

Last thing I did, after maf clean worked, was hit the highway and floored it from 30 to 80 to get a good clean burn thru everything. Suck excess oil from intake, burn some of the bad running buildup off the o2's, injectors, plugs etc..