You did mention it but we are on page 2 now and close to 3, the number of people that will be bothered to go back and check your model details is small, they are more likely just to move on.

Just my

 

Norri, I updated the signature. Hopefully none of the folks who have been chiming in will lose interest yet. Still need help.
FYI guys...for the heck of it I just plugged in the elm to my gmc truck to scan it for comparison and immediately noticed that the fuel trims on that vehicle are very stable and close to 0 all around (+- 3). They do not jump up and down all over the place either, whereas the jag trims are very erratic and constantly bouncing up and down.
The other big difference I noticed was that mafs flow on the truck was at 25 g/s at 2500 rpm, yet the jag mafs flow is only showing as 11.6 g/s at 2500 rpm. Even though 2 different animals, does this tell us anything?
Thank you.

 

Truck has worse mpg.

Honestly the truck is irrelevant.

 

folks, I know some of you may be tiring of this thread, but I am still not quite done troubleshooting this issue. If anyone can jump back in, I'd appreciate it greatly.
Currently the situation is this.....I got rid of the cel after replacing the now repaired climate control module, but still have incomplete 02, evap and comp monitors.
The fuel trims at 2500 rpms in park look good from what I know. The stft's are below +10 and the ltft's hover around 0.
But at cruise speed in overdrive on freeway (65mph, 2,000 rpms) the stft's seem to go to +25 and stay there for extended periods, occasionally dropping down to below +10, while the ltft's stay barely above 0 at up to +3.
I am curious why the stft's are so much lower at 2000 and 2500 rpms in park, but in gear and driving they go up to +25?
Also, I can hear a repetitive clicking noise somewhere in the engine area that sounds a little like the a/c compressor kicking in and out, but it is not that. It clicks about every 2-3 seconds. What is that?

 

Possibly the EVAP check valve? That clicks when doing the system leak check. Mine was bad which caused a P0456 (IIRC) and incomplete monitors

 

With time you can expect it will move the LTFTs and reduce the STFTs. May also start setting codes, probably pending ones to start with.

However, with unset monitors it is much harder for it to set codes because there is so much it cannot trust.

Have you followed the drive cycle info with care?

 

Jagv8......I trust your input a great deal. This is so puzzling to me. Frankly, the drive cycle is so hard to perform completely in traffic congested so california, it is nearly impossible. ie....decelerate from 60mph to 0 basically coasting to a stop. I have tried doing that on freeway by pulling over to the right shoulder with hazards on, but when doing that, you are freaking out everybody else on the road and attracting highway patrol attention, which I dont invite with my expired registration due to smog. If you can resend me the drive cycle link specific to the vehicle, I will try again.
The car is behaving as if I am making progress but just can't past those 3 incomplete monitors. I drive the car with elm on in the morning to check for reset progress and no lean codes pop up, but each day in warmer afternoon, wife reports that the "restricted performance" momentarily appears then disappears. I check her car when she gets home and find 0174 pending. Clear it and do the whole thing over again next day.
I have gotten the 02 monitor to reset to complete once or twice, leaving only the evap in the way of probably clearing p1000, but when it reappears, I seem to have no control of clearing it.
Last thing I can think of is to replace new mafs with a different brand and see if I get lucky.
Jaguar s type 3.0...cant live with'em, cant live without'em

 

Remember that the fuel level in the tank must be above 1/4 tank and less than 3/4 (approx.) for the EVAP test to take place.

 

As previously reported, off-brand MAF sensors have been known to throw various codes on these vehicles. I understand your unwillingness to cough up the necessary cash to purchase an OEM MAF sensor at this point, but that may indeed solve most of your issues. If you could arrange to "borrow" one from another willing S-Type owner in your vicinity, that could be your next step. Ask for that favor here on the forum and see if any willing participants respond....

 

DO NOT CLEAR IT.

Every time you do that you also CLEAR all the monitors.

BTW, you probably have to fix the cause of the P0174...

 

yes, I am trying to find the cause of the 0174. new mafs, new maps, new fuel filter, new gas cap, new imt orings, new 02 sensor on bank 2 upstream, all new coils and plugs, smoke test performed with no leaks detected, several doses of fuel injector cleaner........what am I missing?

 

EVAP & Purge system along with injectors on bank 2

 

not sure what to check or replace on the evap/purge system, but the prospect of taking the upper intake off again and messing with fuel rack is daunting to me. Not sure if the injectors are beyond my level of confidence. Today the 02 monitor reset. Hoping it stays that way. I am not erasing the ecu until I see if the evap will reset by itself for a day or two. I just reread the fuel trims at 2000 and 2500 rpms in park, and for what its worth, they are much improved since this morning. ltft's are reading 0 and the stft's have dropped all the way down from +25 to -7 and -8.... not sure how that happened but i did have the battery disconnected last nite to replace the climate control module. Maybe the computer is relearning???

btw, air conditioner working great again. I found a place on ebay that takes your climate control module and repairs any circuitry or components for $99 and ships t back to you with a 5 year warranty.

 

I have no experience with the EVAP / Purge system but I can tell you that after I replaced my purge valve in my XK8 my fuel trims came in back in line with each other my one side was way off. No Codes! As for the injectors hard to say they are the problem that is why I suggested using the BG44K. Yes you can get it in your area but mostly sold at dealerships or your better auto repair shops. It is the best I have found! Correct me if I am wrong but it seems that after you used the other fuel additive you code did not come up as often. Just my thought!

 

Was a proper smoke test done, including EVAP etc? It looks like no.

It's possible of course to let it settle down, set codes, and look at freeze frame data to see when it's unhappy then watch what activates at that time. But you do need someone who has a clue about modern engines (the last 30 years or so). They're rare than you might expect.

 

Gus.....the fuel trims have improved for whatever reason, and it is not setting the hard code for 0174 with cel in last few days. There is a "pending 0174".
Jagv8...re the accuracy of the smoke test, I have no idea because I dont know how to do one myself. It is a local shop with couple of youngish mechanics who always have a full lot of customers waiting their turn so I take that as a positive sign that they are popular. I watched them to the smoke test. they used what appeared to be a specially designed device, pulled off the air intake and mafs, plugged the throttle body with a big stopper and forced smoke into the engine for at least 20 minutes all the while peeking closely all over, and I helped. There was no visible smoke exiting anywhere except when they removed the throttle body cork, and smoke did escape from the throttle body. They declared "no leaks evident".
I have contemplated getting a second opinion smoke test from another shop.
Drove the car again just now after all night in garage, and trims about the same. stft high but ltft low. Only p1000 and evap monitors incomplete. PENDING P1000 AND 0174......does anyone know with certainty if the vehicle can endure a smog test if codes are only PENDING? Somewhere I read that PENDING codes are invisible to emissions testing. True or false?

 

Both Gus and I have left valuable clues on this issue above. Smoke test won't find it.

 

ok Mikey, I take it you push me to the evap purge valve? I will gladly purchase and install a new one........can someone please tell me where it is on a 2005 s type?

 

Search on this forum reveals:

https://www.jaguarforums.com/forum/s...y-45876/page2/

Searching here, JTIS and JEPC all make life easier

 

Jakesdad, Here's to long shots . . . .but one bank lean can be an exhaust leak right before upstream 02 sensor.

I chased all kinds of things on top side of engine, until I checked the downpipe flange right before 02 sensor on bank 1. And bingo! A small exhaust leak was pulling extra air in right before 02 sensor and throwing lean on bank 1.

That was problem . . . after a bunch of messing around with MAF, injector cleaner, searching for vacuum leaks, etc. (all worthwhile perhaps, but not the solution).

Schrodinger explains it all very well: