Hey Guys,

I was driving my 01 XJR last night and noticed that the amber light would come on for a second or two with "Restricyed Performance" and then go away, then come back, then go away. I accelerated quite hard and the car backed off like it was being held back, but there was no check engine light. Later I put my foot down and the car fully accelerated but then the engine light came on saying restricted performance. Now the engine light is the only thing that displays. I have tried to go through all the posts to see if I could find an answer but could not find a definitive answer. What's all this about MAF sensors? Where is it at and is it easy to clean/replace. I have just bought an ODB 11 scanner - is there a website that displays the codes so I know what is wrong with the car? I've only had it two months and to tell you the truth I don't think the lady who had it before me has changed the plugs or air filter. The car runs great and Jaguar gave it a clean bill of health before I bought it.

Thanks in advance

Steve

 

IF YOU HAVE A SCANNER POSTS CODES AND ILL TELL YOU WHAT THEY MEAN

 

Hey Here is what I just learned at of all places AUTOZONE:
1) The MAF (Mass Air FLow) sensor is located just inside the duct that attaches to the air filter tank
2) I had a Dash Warning (Engine Safe Mode) that AUTOZONE tested/gave me for free of "P111" (restricted air intake)
3) I bought some MAF cleaner spray and cleaner for the reuseable K&N airfilter that I use
4) The air filter was a MESS after only one year (so it works wonderfully) I cleaned it with the kit cleaner and now...
ALL IS WELL no more dash messages and performance is back to top drawer GOOD KITTY.

Lessons learned:
A. clean the air filter every oil change
B. Use Local auto parts store to detect codes for free

I would be very interested on the code detector that you have purchased... but what good is it without the chart of code translations?

Scott
2001 VDP Owner For-Life
Mint condition British Racing Green

 

there are several places that you can get the code translated .. my obdII reader ($60) actually translates the codes in professor mode. Also, there a list of code translations in the JTIS electronic manuals. Also, in the past I've just googled the code and the word "jaguar" and I'm pretty sure a list came up - it's online somewhere. Glad you got your car running tip top again.

 

I checked the codes

P0328
P1642
P1111

Any help guys would be grand.

Cheers

Steve

 

here

seriously man......google will do it.

P0328 - knock sensor 1 circuit high input (bank 1 or single sensor)
P1111 - intake air temperature sensor circuit intermittent high voltage
P1642 - fuel pump monitor circuit high input

sounds like you have some electrical issues that are beyond my knowledge.. Or.... you may need a new air temp sensor - I believe the XJR has 2 - the main one next to the air flow sensor, and there's one near the supercharger (at least in a 98).

 

p1111 for jaguar is a readiness code that obd2 readiness checks have completed and can be scanned and pass a state insp, you need this code after clearing codes(you get p1000) and or replacing battery. I would only pay attention to the p0328 for the knock sensor. This will turn on restricted performance since detonation left uncontrolled will break an engine real quick, and when it reads this fault, it retards the ignition which is why it runs like crap, in addition to restricting performance and starting out in 4th gear. bank 1 passenger side US, drivers UK, unplug the black 2 pin connector to the knock sensor, actually just do both, clean the connectors and reassemble, if the codes returns, replace the knock sensor

 

Cheers BRUTAL - where is the knock sensor by the way? Does this sound strange - I was fidling about with the car trying to get the engine light to go off and I took my gas cap off and started the engine......the light went off straight away. I put the cap back on and the light stayed off. I turned the car off, then on again and the light has since stayed off. I brought the car to work this morning and no engine light so far. Do you think I need a new gas cap? Could it be this simple?

Cheers


Steve

 

THE KNOCK SENSORS ARE UNDER THE SUPERCHARGER/INTERCOOLERS, BUT THE WIRING CONNECTORS ARE ON METAL BRACKETS. 1 ON EACH SIDE IN FRONT OF THE INTERCOOLERS, 2 PIN CONNECTORS BLACK AND WHITE, AND BROWN AND WHITE, THERE'RE ALSO 6 PIN CONNECTORS MOUNTED TO THE BRACKETS AS WELL. THIS IS WHY I SAID TO UNPLUG AND CLEAN AND RECONNECT CONNECTORS. ON THE GAS CAP STATEMENT-NO! JUST COINCIDENCE, MUCH LIKE WHEN I DO BRAKES, OR AN OIL CHANGE THEN THE CHECK ENGINE LIGHT COMES ON AFTERWARDS, AND WE GET BLAMED FOR DOING ITTHAT WOULD BE LIKE BLAMING A PLUMBER FOR MAKING YOU BATHROOM LIGHT BURN OUT CAUSE HE JUST FIXED A LEAK IN YOUR TOILET!!!!!!COINCIDENCE, COINCIDENCE, COINCIDENCE

 

Steve,

The CEL is not some magical thing that just goes away from fiddling
I know a big thing people say is that CELs can be as simple as the gas cap not being on. That's completely true, but that's not your case. As you noticed, modern cars have error codes. Those codes tell you exactly where the fault is, which can be a great help in diagnosing things. There are certain tolerances for each part, and when the central computer notices something unacceptable, it triggers the CEL. You get it to go away by fixing what's wrong. I know all you see is a light, but the code reader tells you what's going on so you don't have to guess.

Like Brutal said about the plumber, your codes are for Knock Sensor & IAT. A gas cap won't have ANYTHING to do with your CEL right now.

Since it's coming and going sporadically, I'd lean towards a bad connection. Could be shorting out or something. After you check the knock sensor connection, clear all of them and check about 2 weeks later. Some codes will be stored in memory, but not actually throw a CEL. I don't know if the IAT code is like that or not, but it could be and may not really be a problem.

 

Cerebus - thanks for the response. I am kind of clinging onto it being a bad connection or something - we shall see. I can imagine taking the supercharger off to replace the knock sensor will be a complete pain in the ****.

Thanks guys

Steve

 

I don't think you'd need to take the blower off to get the sensor, but I'm just guessing from the fact that it sounds like you can reach the connectors without taking it off.

But, Brutal knows these cars, I think he's a Jag mechanic. I'm just another dweeb still learning about Jags....haha. Wait for him to reply again for definite answers about the sensors. Haha.

 

You may have a electrical circuit problem. The 1642 code is not the fuel pump, it is the CAN circuit, you may have a bad harness or connector. The 0328 is the knock sensor, but as has been said, it may be the harness or connectors or even the CAN circuit. If you are adept at chasing electricxal faults, get onto Alldata.com, go into the codes and follow the steps to check the circuits. There is too much involvedto type out here. My guess, you have a short in a cicuit or loose or corrodedconnector pin.

 

By the way, if you follow all the tests indicated, you will be testing the knock sensors, which you needto do before you even think of digging them out of there! It takes a long shovel.

 

yes it does, but the good news is I still lean heavill on poor connection at the 2 pin connectors for the knock sensors, rather than the sensor themselves. The connectors are numero uno for that problem, then is it keeps reoccuring, go from there, and you only have to remove the intercoolers on each side youre doing to change, not the blower. and yes Im a Jag tech

 

I am interested to see where this one goes.

 

Hi Sparkers/Steve,
if you are still around - how did this end? I have had the exact same symptoms on my xj8-99 so I'm curious. I have just gotten a code reader with live data recording, but unfortunately it's messing with the car, creating error codes itself, setting the car in restricted mode... so I'm not sure I'll be able to read the codes once they occur.

 

I was able to capture the code today - 0328. (For some reason this code is not stored, not even as pending, in the car after it's turned off, but I scanned it while the engine was still running). So I'll definitely be looking at the knock sensor connectors.

Much appreciated if someone can tell me where I find them?

 

Reading this post makes me think this is what is going on with my car like I said in another thread the shop changed the MAF the air cleaner and changed the air filter so maybe it is a knock sensor causing the restricted performance and the hesitation at full throttle?

 

get the codes, why are you still guessing.

put fuel treatment in, get correct gas, clear the codes and if/when they reappear get them read. report back here for more help