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Good move on the smoke tester. There are way too many opportunities for air leaks.
Yeah, I figured I'd break down and get one. I bought one online for under $100. The more expensive ones seem to include the pump which I don't need. I've got a small pancake compressor that I can use, or I can run a hose from my big compressor, but either way the one I got has a flow adjustment knob to reduce the flow.
For smoke injection, look at the vacuum line to the fuel pressure sensor, at the end of the fuel rail.
Will do.
Your trims are somewhat ok. Codes trip at + or - 25, as in adding or removing 25% fuel as compared to the base fuel tables. For what it's worth, you can feel/tell the engine runs assisted with trims. It is less responsive to throttle input, it seems to "ping" going uphill at low rpm. Not super fun, not what driving a big v8 should feel like. That is why you want to keep your trims under, say, 5% on each bank (less than 10% total, in a way).
I'm not getting any pinging but the throttle response does seem to lag a bit. So it looks like my Long Term Trim on Bank 2 is high?
Also, remember that fuel trim numbers are really a matrix of numbers, indexed by engine load and rpm. Each bank has its own matrix.
Last point: normally, leaks will have more relative importance at low rpm and low load (high vacuum). When your trims are high at idle, it is a sign pointing to air leaks. If trims remain high at higher rpm/load, it generally points more to the air flow meter.
The trim levels pretty much stayed the same at 2,500 rpm as idle.
Best of luck, keep us posted.
I'll definitely post more once the parts and equipment get here and I'm back to being able to work on it. Thank you for the info.
Permit me, please, to jump in here. Not trying to hijack the thread, just piggybacking in order to avoid starting a redundant thread.
I fixed a vacuum leak, got weird rich errors on both banks. Installed new MAF and all the mixture and hard starting gremlins went away. I should have done this two years ago. But now I'm back to the same problem as @OCJoeR - the cat monitor won't set. Again.
I went to San Diego the other day, R/T of about 230 miles and the CAT monitor would not set. On the way back I monitored LTFT and Downstream O2 Voltage.
First question - at idle and low speeds, LTFT bounces from zero to low single digit numbers. At 80MPH they become rock steady, -10.2% on Bank 1, -8.66% on Bank 2. So, about 1.5% difference between the two, which doesn't seem like much. But are these numbers too high? The car runs great, plenty of power, nothing odd.
Second question - both downstream voltage numbers bounce wildly all over the joint. From 0.8 to 0.1, and all numbers in between. This can't be good. Could BOTH cats be on the way out? (BTW, the O2 sensors on Bank 1 are both new, the ones on Bank 2 came with the car and *might* be original.)
FWIW, all monitors are set except CAT MON, no error codes for anything else, like misfire.
Permit me, please, to jump in here. Not trying to hijack the thread, just piggybacking in order to avoid starting a redundant thread.
I fixed a vacuum leak, got weird rich errors on both banks. Installed new MAF and all the mixture and hard starting gremlins went away. I should have done this two years ago. But now I'm back to the same problem as @OCJoeR - the cat monitor won't set. Again.
I went to San Diego the other day, R/T of about 230 miles and the CAT monitor would not set. On the way back I monitored LTFT and Downstream O2 Voltage.
First question - at idle and low speeds, LTFT bounces from zero to low single digit numbers. At 80MPH they become rock steady, -10.2% on Bank 1, -8.66% on Bank 2. So, about 1.5% difference between the two, which doesn't seem like much. But are these numbers too high? The car runs great, plenty of power, nothing odd.
Second question - both downstream voltage numbers bounce wildly all over the joint. From 0.8 to 0.1, and all numbers in between. This can't be good. Could BOTH cats be on the way out? (BTW, the O2 sensors on Bank 1 are both new, the ones on Bank 2 came with the car and *might* be original.)
FWIW, all monitors are set except CAT MON, no error codes for anything else, like misfire.
There is an imbalance between the air flow metered and the fuel being injected, so the car is taking fuel away.
Have you tried adding a can of injector cleaner to you fuel? Was the MAF a genuine part or some cheap brand? Other obvious things to check/replace are spark plugs and air filter if they are old.
There is an imbalance between the air flow metered and the fuel being injected, so the car is taking fuel away.
Have you tried adding a can of injector cleaner to you fuel? Was the MAF a genuine part or some cheap brand? Other obvious things to check/replace are spark plugs and air filter if they are old.
MAF is genuine Denso. Filter is a couple years old, 5K or 6K miles on it, but I can look at it. Plugs same age, probably around 5K or 6K miles on them. I've owned the car for just under 2 years, but it's only really been reliably drivable for a few months.
Fuel pressure regulator is also less than 2 years old. Injectors are an unknown quantity. But no misfires. I can try some injector cleaner.
MAF is genuine Denso. Filter is a couple years old, 5K or 6K miles on it, but I can look at it. Plugs same age, probably around 5K or 6K miles on them. I've owned the car for just under 2 years, but it's only really been reliably drivable for a few months.
Fuel pressure regulator is also less than 2 years old. Injectors are an unknown quantity. But no misfires. I can try some injector cleaner.
So, you think those numbers are too high?
The numbers aren't too high because you aren't triggering a code - there is plenty of room left for the computer to compensate for whatever is going on. Obviously though the ideal is to have them as close to zero as is possible on a 20 year old car.
For the cat monitor not setting you probably just need to drive it more. My car has similar figures to yours for the downstream O2 sensors and the CAT monitor is set, although where I live they don't check OBD data, they just test at the tailpipe.
Joe looks painful, I have had hand issues also.
I recently got a 2003 XKR convertible, am in mission Viejo, where are you?
Hi Brian,
I'm in Placentia. I'm going to PT now to get all the fingers working again. Just have to do all the exercises every day so I'll be able to pull the clutch handle again.
My '01 is making me crazy because the system won't clear the CAT monitor. I've got a set of downstream O2 sensors coming in next week. With any luck I'll be able to get under the car and change them out and see if they were the problem. I'm going to run to the auto parts store today and pick up some MAF sensor cleaner and take that out and clean it. I found a video somewhere that said that might a problem, so while I'm waiting I figure I'd try that, along with cleaning out the throttle body with some carb cleaner. I've got an extension on my registration until the end of April. Hopefully I'll figure it out by then. There are just so many "fixes" out there but no one seems to have a real solution. I've gone through all the suggested "drive cycles", nothing. I've driven the car at least 800 miles since I cleared the original fault code, nothing. We shall see.
Just for jollies I cleaned the MAF sensor and it did not help clearing the CAT monitor.
The Downstream O2 sensors are supposed to be here Friday. The physical therapy is helping my hand/fingers get back to almost normal. At least I'm able to type now, lol. I'll see if I can get the car up in the air and change out the O2 sensors this weekend and see if that does anything to clear the CAT monitor. If it doesn't I have no idea what I'm supposed to do with this car. I have an extension until the end of April to get it registered. If I can't get the monitor to reset it won't pass the smog certification. I'm in the People's Republic of California, so it doesn't matter if I have pure oxygen coming out of the tail pipe, they only look at the readings on the OBD2 to do the smog test so I'm pretty much screwed.
I'm approaching the same thing. I'm going for a drive to TJ and back tomorrow to test the new set of injectors I installed. They seem to run leaner than the old ones. So much so that it triggered a lean condition. After my friend and I searched we found a few vacuum leaks that the smoke test didn't find - the T connection that plugs into the left side of the throttle body, that stupid little hose with the worthless, rotted out plastic sleeve on the right side of the TB, and, weirdly, the left bottom edge of the intake manifold, cylinders 5 and 7. Oh, and the dipstick tube. I fixed the dipstick tube and got the T connector securely plugged in. That seemed to fix the lean condition. Preliminary tests show that Bank 2 is running slightly leaner than Bank 1, probably due to the small vacuum leak on that side.
Anyway, my point is that if the monitor doesn't set this trip, after replacing MAF, injectors, vacuum leaks, and a poorly fitting "full load" breather tube, I'm also out of ideas. At that point I'm going to put spacers on the downstream O2 sensors and see what happens.
Just an FYI, we found an aftermarket cat that will probably fit in the areas the old cats occupy now. They would require an exhaust shop to weld a flange on top, and an elbow pipe at the bottom, along with sensor bungs. They are CARB compliant and, IIRC, under $400 each. This may be an option and I can send you more info if you like. If nothing else works, and the spacers don't either, mine is going onto BaT as an out-of-state sale.
The Denso O2 sensors should be here tomorrow, so says the tracking info. Right now the weekend looks to be open so I should be able to get them installed on Saturday. I picked up one of those smoke systems so I'll hook that up and see what it shows. I used the MAF cleaner on the sensors last week, maybe I'll give them another shot too, I've read in some posts it takes a few uses of the cleaner to get them to be clean. After that I'll hook up the OBD2 and see if I still get the INC reading on the CAT monitor. Do you have the link for those spacers? I thought I had it bookmarked but I can't seem to find it.
You would think there is someone who would know how to resolve this problem. Seems a shame to scrap a car because of a computer issue that no one can solve. Maybe I'll ask my 12 year old grandson to attach his game playing device to the car. He'll probably figure out how to fix it. Nothing like designing a car that absolutely can not be fixed.
The Denso O2 sensors should be here tomorrow, so says the tracking info. Right now the weekend looks to be open so I should be able to get them installed on Saturday. I picked up one of those smoke systems so I'll hook that up and see what it shows. I used the MAF cleaner on the sensors last week, maybe I'll give them another shot too, I've read in some posts it takes a few uses of the cleaner to get them to be clean. After that I'll hook up the OBD2 and see if I still get the INC reading on the CAT monitor. Do you have the link for those spacers? I thought I had it bookmarked but I can't seem to find it.
You would think there is someone who would know how to resolve this problem. Seems a shame to scrap a car because of a computer issue that no one can solve. Maybe I'll ask my 12 year old grandson to attach his game playing device to the car. He'll probably figure out how to fix it. Nothing like designing a car that absolutely can not be fixed.
Let me know how the TJ trip goes.
Put "Dorman 42109 Extended Spark Plug Non-Fouler" into Amazon and they should come up. About $12 for the pair.
The trip was fine but after 250 miles, more or less, the CAT monitor still hasn't set up. It's never taken this long to set and I think it's not going to. Everything I've done to the point has been a net benefit; the weird hard starting thing seems to be gone, it idles well, the LTFT is slightly leaner than before. But the downstream O2 sensor voltage is still allover the map on both banks and I figure that's why the monitor won't set. I note that on my old BMW the downstream voltages are pretty stable. They fluctuate a bit, but nothing like the Jag.
The spacers will be in today sometime, and I'll install them over the weekend. I'm helping a friend change the rod bearings on his S85 engine and that's taking up a bit of my spare time.
I suspect that I have two bad cats, a problem I've never encountered. Thanks to Kommiefornia we're supposed to use CARB-compliant cats which are double or triple the cost of the EPA-compliant ones. So, I'm not going to waste a thousand or two more on this car. If the spacers don't do it then it's going up for sale. It will make somebody a nice ride, as all the hard stuff has been done and I now have no problem driving it anywhere.
The O2 sensors showed up yesterday but I'm not going to be able to do any work until tomorrow, babysitting assignments today. At least the physical therapy seems to be helping my hand so I'll be able to use the tools to work on it.
I watched one more "how to clear your CAT monitor" yesterday and it claimed that running the engine (after warm up) at 3,000 rpm for 3 minutes will clear the CAT monitor. I'll give that a shot today but I'm not expecting anything. I've got the smoke machine ready to go so assuming this 3,000 rpm thing doesn't work that's where I'm going to start tomorrow morning. I'm with you on the bad CATs. I've only got 63,000 miles on this car. Although given what appear to be some of the other intentional Jaguar design flaws (those dumb headlight washer covers that fall off and cost a fortune) I wouldn't put it past them to use CATs with a 50,000 mile useful life.
Just for jollies I think I'm going to run over to the smog check place and see if they can check the tailpipe gases without the CAT monitor being cleared and see what is actually coming out of the tailpipe.
If I ever get this issue fixed to the point where I can register the thing it's going up for sale as soon as I get back from DMV. I recall hearing all kinds of bad things about Jags back in the day, electrical issues etc. I thought they might have fixed those issues but I guess I'm wrong. They still make what appears to be an unfixable car. Ah well, back to a pre 1975 vehicle.
Well so much for yet another internet theory on clearing monitors. I tried the 3,000 rpm for 3 minutes and still have the INC for the CAT and CCM monitors. I'm going to do the smoke test and see if I have any holes in that system tomorrow morning and then take the old downstream O2 sensors out and see what they look like. I'll probably replace them since I have the new ones and see what happens. In the mean time if anyone out there has a clue on how to get these things to clear do let the rest of the world know.
Well not another site says that there's a second part to the CAT reset "drive cycle". Apparently after the 3,000 rpm for 3 minutes I need to drive the car above 10 mph and 1,500 rpm for some time for it to clear. We shall see. Next thing you know I'll have to stand on the corner and bark at the moon three times and turn around in a counter clockwise direction facing west. Damn, just give me back my '46 Chevy truck!!!!!
I feel for you Joe. Last month my wife's 2006 XK8 passed the final emissions inspection it will ever need here in North Carolina. It officially turns 20 years old next January 1st and according to our laws, emissions will no longer be a part of the mandatory annual safety inspection from now on. For vehicles less than 20 years old, they will pass inspection as long as no more than ONE of the readiness monitors is incomplete....
Well not another site says that there's a second part to the CAT reset "drive cycle". Apparently after the 3,000 rpm for 3 minutes I need to drive the car above 10 mph and 1,500 rpm for some time for it to clear. We shall see. Next thing you know I'll have to stand on the corner and bark at the moon three times and turn around in a counter clockwise direction facing west. Damn, just give me back my '46 Chevy truck!!!!!
Refresh my memory. Did you say you'd measured the downstream O2 sensor voltages? Did you check the cat temps, inlet and outlet.
My cat temps at the outlet were between 420 and 450 degrees, which seems far too low. Also, the voltages are all over the joint. By contrast, the voltages on one of my BMWs are pretty steady.
