anybody out there have the test procedure for trouble shooting the egr valve and system. i'm getting a CEL and code that tell me the is a problem. either a vacuum leak or a bad egr valve, or even a bad gas cap. need help please.

chris

 

The 2001 XJ8 does NOT have an EGR valve so no test is going to help.
What DTC???????????????????
More info please!!!!!!!!!!!!!!

bob gauff

 

Nope, no EGR... must be looking at a non-jag OBD code chart. What was your CEL OBD code?

 

first off, yes, i have no egr. i was mistaken. i meant purge valve. testing. i found a test procedure from my saab and trouble shot the purge valve, 31 ohm reading and battery voltage at the supply pin.

however i'm no furhter off. i spent all day yesterday going hand over hand trying to find a vacuum leak. i had a p0171 and p0174 code as well as a p0443 code. i found what i thought was the problem and drove to new orleans (long story) in mardis gras traffic to get code cleared by a dealer. all wsa well until i got bak to batonr rouge some 60 miles away. i stopped to fill up with gas, got back on road, and after 3 or so mlies, the check engine came back on. pop goes the bubble. i take it to a zone and again i have the p0171 and p0174.

i thinking unmetered air (vac leak) or bad maf sensor. however, i think if i were to continue driving it i would again get the P0443.

i did previously to clearing codes properly clean the the maf sensor. sure i did not damage element.

I sure could use some help here.

 

chris:
Ok - it sounds like P443 was left over- probably from a gas cap leak. I realize you jave answered this, but I am going to ask again for effect! Are you sure about vacuum leaks? There is a small hose on the driver side too. And I suppose any leak to the crankcase like the oil stick and cap could do it. As you know, MAF could do it and there are some reported failures. Have you checked fuel pressure under load? If you know someone who has an OBD scanner that gives charts, you might look at STFT and LTFT to see if it codes at high or low rpm and load. And don;t bother with the dealer for code resets. I figure they told you at the Zone that they can do the reset. Or Advantage Auto Parts.
Good luck, and keep us posted.

 

The P0443 is a '2 trip' fault meaning it has to occur 2 times for the MIL to be illuminated.

Possible causes

EVAPP valve to ECM drive circuit:
open circuit, short circuit, high resistance

EVAPP valve power supply circuit: open circuit

EVAPP valve operating vacuum hose leak /
blockage

EVAPP valve failure

 

Since you say you're sure you did not damage "the (singular) element", I wonder if you cleaned everything... see attached pictures in this post:

https://www.jaguarforums.com/forum/s...8&postcount=18

Just a thought.

 

very interesting thought TTL. i certainly did miss that. i do as you say and clean these as well. i'll keep up the post.

by the way, do you know any test procedure specifically for the MAF sensor?

thanks

chris

 

Sorry, no... wish I did. FWIW, I was very leery of trying to clean those two components inside the case, but my MAF sensor cleaner spray can said it was safe so I trusted it. I'm not 100.00000% sure that I've solved the problem because I did my test drive in such cold conditions, but I'm pretty sure I didn't make the sensor any worse.

 

ttl, i found and cleaned the other parts of the MAF as you sugessted. good point. thanks

i had a check engine light on my son's xj8. it has p0171, p0174 and p0443 codes. i got the codes cleared and stoped them from comming back on by removing the vac line the draws vac on the cannisters and plugged it to see if it is the source of leak. now driving it and 6 of 7 sensors are clear. i now get the check gas cap warning when driving. i'm fairly certain that there is a vac leak either on one or both cannisters, a hose or there is a proble with the cap.

any ideas or thoughts out there.

chris

 

Well, you can trace every inch of the hose and remove the valve and check for leaks. The pros use a smoke generator to pressurize the system and look for, well, smoke.

 

I have seen the plastic canisters crack. I would check the 'O'rings for the plastic pipes that connect the canisters to the system. I have replaced them after a 'smoke test' showed one leaking. The only way to get them from the dealer is to buy the entire plastic line. If one is torn/damaged you can get an assortment of generic 'O'rings and find one of the correct size. Lube the 'O'ring wth silicone grease or spray lube.

You will get a fault if you block off the vacuum line from the purge valve. It is required for the system to operate properly.

Could be a faulty canister close valve or a poorly fitting fuel filler cap??????

bob gauff

 

Bob And Ross,

thank you very much for your response. i understand the car will code because of the evap purge vac line plugged. i did this to eleminate the maf (bad metered air) as possible cause. i fill confident now that the problem is down stream of the purge vent line towards the cannisters. I believe i will first replace the gas cap and wait for it to code again. the current cap apears somewhat corroded and may be the cause. form there, i plan to remove cannisters and do bench top leak check with vac pump. i'll be sure to check o-rings as you mentioned.

One thimg Bob, you mentioned "close valve" in your last response. that is this?

Also, i'm open for other of modifications to my trouble shoot plan.

thanks again,

chris

 

Here are some TSBs to look at.

The CCV TSB is for the XK but it works the same on the XJ

bob gauff

 

bob,

this is awesome stuff. wouldn't the items from the attachments be a recall type repair? it seems jaguar dealership should have mentioned this to me when i visited there service areas questioning about getting the car worked on for the CEL. my earliest date is 3/22/11. i even went to the parts people inquriing about a new gas cap. they did have the one for my car in stock so thought i would wait until i got it officially check out before i ordered a new one. this shows me me a lack of integrity by my local dearlership.

I plan to use this knowledge wisely. again you impress me. you remind me of a person i know of on a saab site a use. he very concise, direct and correct on all his post.

thanks again, i'll keep you informed of my progress.

chris

 

chris:
Although on an emotional level I feel like you do, think about things from a practical lrgal point of view.
Just because a car company finds that a particular problem occurs frequently enough to publish what is basically a help document for their internal service use, does not obligate them to recall and correct problems for free, unless the impact is of the type that would call into question the prioduct's "merchantability and suitability for use". Many safety items, or .by law, certain emissions issues are candidates for recall. Many TSBs are just hints for the repair guys on better ways to do something.
An automobile is known to need repair from time to time. There is a stated warranty and it states what parts are covered. The owner covers averything else outside or after the warranty.
And just because a manufacturer determines how to make a part better, it does not obligate him to offer that part, free, to everyone who bought the product previously.
Just my $.02

 

ross,
your point is well taken and i do understand it. like you said, an emotional thing. trying to fight these check engine is quite frustrating, especially for a DIYer.

thanks for your 0.02 cents,

chris

 

Does a North American spec 2001 XJR have an EGR valve?

 

plums:
I am not absolutely sure because my XJRs are both AJ26, but I am pretty sure they do. The EGR function in an XJ8 is apparently done with overlap using the VVT system, and since, of course, the SC has no VVT, it requires an EGR.

 

Ahh... that makes sense then. Thanks!