hi everybody
this is first time i am posting a thread to find a solution
never needed to before as searching always solved all the questions
i tried to search on this issue to but couldnt find any layman solutions i could understand

so here it goes
2003 s type r , 55000 miles or 87000kms
engine knocking and pinging when i give it throttle in any gear but stops as revs rise up or as it shifts to lower gear
i dont hear anything when full throttle and performance has gone down a bit since this started
not getting any codes , and idles and runs perfectly

getting 180miles to 220 miles per gas tank till low fuel warning so dont think i am running lean
but spark plugs had whitish deposit on them when i changed them recently
so they say a different story

cleaned the maf sensor with maf sensor cleaner but didnt solve anything

dont really know how to check vacuum leak
i do have access to obd reader let me know what to check but i am very new to obd live stream so please explain in layman terms

thanks guys
really a great community and have solved lot of my problems since i became a proud jag owner and website member

 

If it does live data that's good! Which tool is it?

Have a hunt to see if you can check the OBD monitors. All the supported ones should be marked as OK (aka set aka complete, no-one sticks to just a single term!).

It could be a critical sensor that's out of spec or it could be such as an air leak or a stuck actuator. A pic to get the kind of things involved is here OnBoardDiagnostics.com - Engine Basics

Or it could be a blocked cat.

Air leaks show as LTFTs being away from zero by more than a few (say 5) percent. Check them with warm engine in P or N at idle & about 2500rpm.

A bad sensor can be harder to see but you can easily check some of them such as ECT and IAT. (The STR also has IAT2 and your tool likely won't report it, but you'd be unlucky for it to be the problem.)

You need to find whether the car (warmed up) is running CL because various sensors are basically not used otherwise.

On some tools you can go round the sensors with engine cold, see if they're plausible, watch them as it warms up and/or watch it go from OL to CL.

There are sites all over the net that explain OBD II (OBD2) and it's way too big a topic to try to put such info here. google is your friend, as they say.

revised acronyms: https://www.jaguarforums.com/forum/s...-jaguar-78910/

 

hi
thanks for the reply helped me get going on diagnostics

1. the tool is genisys spx otc
the readiness test shows READY for comprehensive comp , fuel system , misfire monitor ,oxygen sensor , oxygen sensor heater , catalyst , evaporative system , egr system ,

and shows not available to secondary air system , heated catalyst and a/c refrigerant

no history codes found

pending codes :- p1111 manufacturer controlled fuel and air metering

fully warmed up
@2500rpm

ltft bank 1 : 0%
ltft bank 2 : -0.8%
stays around that and doesnt vary much , maximum i saw on ltft 2 was -1.6%

@ 697rpm or idle

ltft bank 1 : 2.3%
ltft bank 2 : 0.0%
and doesnt vary much either

stft jumps around a lot

ect showed constant around 207 degree and not moving more than 1or2 degrees
IAT was around constant 127 degree

ur right there is no IAT 2

fuel pressure stays above 55 psi

its shows 5 o2 readings
o2 sensor 1/2 stays around 0.80 v at idle
o2 sensor 2/2 stays around 0.80 v at idle
o2s11 current stays around 127 ma ( +- .4)
o2s21 current stays around 127 ma ( +- .4)
o2s31 current stays around 127 ma ( +- .4)

coudnt test from OL to OC
please do explain how to do that and what readings i should look for and what are normal or abnormal readings

thanks a ton jagv8 for getting me started

 

Pah. All P1 codes are (by definition) manufacturer-specific so the tool should not give you that wrong meaning!! (Sadly all too common.) Fail for Genisys.

P1111 is jag code for System Test Pass i.e. all (supported) monitors Complete. That's good news.

The tool also seems rather confused about O2s. There are 4 (each bank, pre- & post-cat). It looks like the tool doesn't support the pre-cat ones (they're the newer technology WB aka linear aka UEGO type).

Sorry, no idea where they may hide the CL / OL status. But all suggests it's running CL as it should.

The trims look good. No signs of an air leak

ECT & IAT look OK if it was a hot day (127, ouch!).

I suspect you'll not easily get much (or any) more from OBD unless you can collect live data as it makes the sound and then review it.

Has to be worth trying MAF cleaner.

If you can figure a way to test the cats (IR gun / whatever) I think that's where I'd look next.

Other things I suppose might? be causes: EGR, PCV, EVAP and coils under stress (usually oil/water on them).

Sorry but you don't appear to have a problem commonly seen on here

 

hi
i searched on p1111 code and everywhere on google it was said as cycle complete code or something like that and was considered normal or good
and the tool also states it as pending code
if i scan for trouble codes it says no codes found !
so i guess it knows its not trouble

yeah i was also confused about o2 sensors , i knew there were 4 and thought it was reading the pre cat ones but now i know it reads post cats

thanks god no air leaks and yeah very hot day with highest at 37 deg Celsius

i did clean the maf a month ago when i put in new spark plugs and the old ones showed lean running with white powdery deposit
and also cleaned the coils then , they was just a little touch of oil at base ,, nothing more

egr pcv ? i knew this was little over complicated for me
not that good with diagnosis ,

so left it at dealership friday morning , replicated the problem with tech sitting beside me and left it his hands and he said its detonation and asked me if i put in regular fuel but i only used 94 oct and tried 2 different pumps before going to them

they told me k&n not recommended (they said so many times ) so finally i agreed to pop in an oem filter
and they scanned the car and updated the software

picked it up an hour ago and thought might update the thread as well

problem is 80% solved but still there tiny bit
they recommended trying different brand of fuel and octane booster

lets try that and see

cheers guys

and

 

Run the highest octane gas you can get...

He is also correct about concern regarding the K&N filter. Oiled filters can wreak havoc on intake sensors if they are even slightly over oiled. This is VERY easy to do.

Keep us updated on it...

 

I think the dealer's comment about octane are way off the mark. These cars do not detonate on 91 or higher octane fuel. There's no need for 94 and especially don't need a (waste of money) octane booster.

If the condition truly is detonation, the knock sensors will cause the timing to retard, eliminating the condition long before the human ear can detect anything.

 

hi
i guess u r right in a way that knock sensors should do it but they cant control detonations as far as i think , detonations occur mostly independently to spark timing
but i checked live stream , it does retard timing by as much as 30 degrees during detonation and it reduced detonation but i think it was more than adjustment values
in ecm could take

i used only 1 pump near my old place since i bought the car and never had any problem ,

filled at new pump on my way to work and it started having detonation
and tried another pump and same thing ,

went to dealership and they updated ecm that reduced it but didnt make it go away
they analysed gas and said try another pump nothing wrong with the car

i tried another pump (3rd one ) and it solved the problem but i rarely heard something or i was just imagining it

so i went back to my old pump and got full tank and i tried everything from braking while accelerating to increase load while going uphill on hot day but cudnt make it detonate again

so end result :- it was most probably bad gas but not brave enough to try those pumps again

thanks everyone heartily for the help
cheers

 

godfatty, no mention of fuel pressure? Change that fuel filter bro. A clogged f/f or failing pump can cause a lean condition, leading to detonation.

 

I agree with changing the fuel filter now. Any idea when/if it has been changed? I have found several cases on other cars where people have paid for it to be changed but since it's pretty well hidden and not easy to check it was not done. I ALWAYS write the mileage on any filter I change. The date is also a good idea. I sometimes forget when it was done myself!

Maybe run some fuel injector cleaner for a tank or two just in case?
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@ bfsgross & clubairth1
Thanks guys , I already did the fuel filter before posting , sorry didn't mention this in my first post
It was changed after I started having problems and before I made my second post with all the live stream readings and it didn't change fuel pressure readings so I guess it wasn't clogged
I put in genuine jaguar filter and fuel pressure stays around 55psi as mentioned in my second post

 

Is 55psi fuel preassure ok?

 

I'd be interested in knowing the actual values you measured. At idle the timing is around 30* BTDC and even in idle with slight throttle this will advance to 42* or so. I'd be surprised that the knock sensors were attempting to pull 30* of timing from that.

It sounds more and more like you simply had 'bad' fuel that caused a misfire, not detonation.

 

55 psi is fine. When I monitor my 2005 STR I get between 45-65 psi with some fluctuation depending on throttle. It most definitely should be moving around some anyway.
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@Mikey
Usually the timing would stay above 30deg yo 45deg during driving on low throttle
Whenever I pressed throttle hard it would detonate and loose power for a second or 2 seconds and then down shift and then move but with still a little bit of detonation happening along
That loss of power came from ecm reducing spark advance sometimes I saw values as low as 5 deg