HELP!! 2000 xk8 90k miles- will go restricted after a drive then parked then restarted. it will clear itself over nite and do it again every day. runs great other than that. most of time it will show p305 sometimes 301 have changed plug and coil. occasionally will clear it self while driving and rarely will come on will driving. but every morning it shows restricted dive a mile or so it will turn off go to work come out after awhile and and start car her comes restricted again.
i know someone here has the answer.
thanks

 

First make sure that everything that you UNDID in changing the plugs and coils is ReDid.. Could be the car is trying to tell you something? 301 is 305 are two separate cylinders I believe... Something ain't right there. OR

If those areHare codes you were getting before you did the work of plug and coil, hard reset the car. Take a pair of vice grips, undo the POS and NEG cables at the battery, use the vise grips to clip them together, back away and leave overnight or for a couple of days if you can. I've never had any problems being locked out of my radio,,, or anything like that, but if you have a radio code keep it handy. Honestly I don't even know if that applies.

Anyways, reconnect the battery, positive term first (others please correct me if I'm wrong) then the negative in one fell swoop. Don't be messing around jiggling the cables on the posts,,, or kinda connecting them. Have the 10mm wrench in hand and tighten right down.

Fully recharge the battery first, of course. Then give it another try.

 

yes did the 2nd easiest thing when the trouble started was the change out plug and coil, mostly cyl 5 is the code. did not think about the reset/flash.
had leaking valve covers and had those replaced. before that it was cyl 8. will try the hard reset. 301 and 305 are on the same bank. they were both wet from valve covers leaking before but are dry now. this error is hilariously reqular. there is no miss (till restricted kicks in) at any rpm.
thanks

 

Can you, have you, cleared the codes?

 

Also, and I just redid mine on an xk8, inspect the harnesses to the coils. Look close. A crack in the insulation might be a sure sign of something a bit deeper. Also, and important, make sure the pins did not get misaligned or bent when pushing the harness/plug BACK into the coil. Because of the heat and stuff going on under the air tight coil covers, I leave the off in the summer. Its just too punishing an environment for electrical stuff IMHO... Anyways

 

Cyl 1 and 5 are not on the same bank on a 2000. They are both at the front on opposite banks.

 

Also, I have no knowledge or information on such things,,, but is there a ground point for the ignition systems on these cars??? A one main ground for each bank, both on one ground? I'm not sure on that...

Why did you suspect the coil and plug as needing fixing, if you don't mind?

 

P0305 / P0301 do not always mean what you mean and even when they do it is uncommon that a human can feel the misfire.

If you keep getting the error(s) you do really need to find out why or you can expect worse (e.g. destroyed cats).

Generally Jaguar list the known causes for each code and the list is most useful.

You may also find it worth checking the fuel trims with care.

 

yes sometimes it wont set. sometimes i have to turn it off and restart to get codes. when the restricted clears its self it will leave the code behind most times. but miss goes away and all is well till drive park and restart just when i think i might get thru a whole day (a couple of restarts) it generally will come back don't miss many days since this started. if i clear the code usually it will come right back but always clears itself overnight. it will be there in morning go about a mile and turns off and purrs like it should. it i could jump around restricted car runs great. no issues. a little issue with cruise catching now and then but dont use it much.

 

the cyl 5 error code.

 

easiest thing besides the flash idea. and easier than going to the injector.

 

hmm that is what a cyl map i saw had and that is how the coils were marked by someone. brings up good point someone had been in there before and marked the coil tops. they wouldn't do that from factory i wouldn't think but they looked like original units.
so that would eliminate my thought that it is the same bank.
thanks

 

yes aware if cat is getting flooded there goes another set of $$$ and smog time is coming up in a month or two, usually passed with flying colors.
thanks

 

yes not the miss- there is no perceived miss i can tell from listening or feel i ment the rough running that restricted installs at 3k rpm
thanks and a good point was going off code and restricted performance. only thing i think i know it does not appear to be mechanical and that is a good thing
thanks

 

i used a wood skewer to move wires around and try and get it to fault no luck. dont lose those cover screws i think they are $6 each if you can find them. my local jag dealer said he couldn't find them but got me the part number. was missing a couple.
thanks going to drain the memory to nite.

 

Hang on - are you revving it parked to 3K? You'll trigger the rev limiter. It'll feel rough.

It's to protect things such as trans.

 

no the 3k is where the bad performance starts on the restricted. below that runs fine. flashing the system today. but starting to think it is dropping the error over night and needs a couple cycles, time, or all of the above to go restricted. somewhat intermittent, but happens most days the same. if i clear it while restricted will usually put back on quickly. the check engine light will flicker often as if trying to decide to code or not. and sometimes won't set but mostly will. strange that the code won't show till i turn off and back on even if light is lit. it is at an indy shop now who knows car well. frustrating him also.
question are there seperate wiring harnes for both banks? i think i read that there is ecm but 2 spark enhancers(probably not called that)
thanks for your help

 

Flicker may be the signal that catalyst damage is occurring.

 

it seems to dither sometimes than go out or go on. not flashing though. maybe should look at injectors trims seem ok though.
i see there is another here with similar but almost backward from my issue. they could have used a scene from my car in the movie.
so had wrencher checking battery and flashing memory we shall see. found out why i think the coils were marked had all plugs changed awhile back.
thanks for keep mulling it over. it is my second most daily driver. and have not really had any problems with it. other than people keep dinging it.
just got it all painted up again so try to keep miles down but take it out at least once a week usually.

 

well the flash did't work but the wrencher tells me he did get an error to valve train sensor so we are going to replace those?
make sense?
thanks