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P0430 or P0420 codes, right?
catalyst below efficiency, right?
And it's not the sensor's fault?
and the fuel trim corections are affected?
and one bank is lean or rich as a consequence?
man, welcome to this thread.
Before being judged, allow me to express the following:
-I am passing my emissions tests.
-im not polluting.
-i am even burning LPG so i am green.
- And as far as I understand,
catalysts can work and these codes will still appear, as of a catalyst converter being under 95% of efficiency...
really? 95 is that far from 100?
i bet that 5% of a car's pollution is way cleaner that the waste done fabricating a new catalyst...
now depending on your countries laws bla bla... dont care. Emissions passed. Car works well. emissions are within standards.
anyways, fixed the cat issue with the classic spacer fix. And i just to confirm it works on a v6 stype.
how:
A spark plug anti fouler drilled to a 0.5inch interior, or
my custom made 35mm tall spacer (pic below), M18 1.5 threads, 0.5inch interior,
was installed to move the probe away a bit.
thats it, $7.
check the before and after catalysts o2 sensors readings below.
if you pollute, please fix it correctly
Last edited by elDariusVargas; Feb 16, 2022 at 07:20 AM.
yes, right allow me to add some quotes for the topic to me more specific:
from other forums: "My understanding of this code (P0420) is that the cat is not functioning at OPTIMUM level (meaning less than 95% efficiency) and by the use of the secondary O2 sensor the computer is throwing off code P0420. Doesn't mean that the cat is no good, just not at 'OPTIMUM' level (95% or better)"
as proof, after the CO and HC tests, my cat appears to be working at a 93% efficiency. temperature tests passed too
and from 1aAuto blog, credits to them for the list that can cause p0430 and 0420: "
yes, right allow me to add some quotes for the topic to me more specific:
from other forums: "My understanding of this code (P0420) is that the cat is not functioning at OPTIMUM level (meaning less than 95% efficiency) and by the use of the secondary O2 sensor the computer is throwing off code P0420. Doesn't mean that the cat is no good, just not at 'OPTIMUM' level (95% or better)"
as proof, after the CO and HC tests, my cat appears to be working at a 93% efficiency. temperature tests passed too
and from 1aAuto blog, credits to them for the list that can cause p0430 and 0420: "
Edit: Thank you haha 🤣 you got me there
my car is fine.
yes, i wanted to at least underline the fact that pollution is not the issue in my case.
and if pollution is the issue in other cases this is not the fix.
the only issue found was the catalytic converter is slightly bellow efficiency.
everything else is like new since it's been taken apart & reconditioned.
remember i told you guys the previous engine had issues with the headgaskets?
right... yes, that's the side where coolant was entering the exhaust. might have poisoned the cat a little bit enough to shoot the code.
cats were removed and cleaned, but the burned residue will only be removed after diving a while.
i the meanwhile i dont want to damage my engine with bad fuel trim corrections.
jaguar didnt invent the catalytic convertor, nor the lambda probe, so im guessing general info could still apply.
and this is the exact point of this post:
IF a v6 (at least) s type is WHITHIN emissions, works WELL, but this readings are present, a Spacer might work.
Thank you for the patience. hope it helps someone as these cars are old and can have random issues.
Last edited by elDariusVargas; Feb 17, 2022 at 07:55 AM.
Thank you, my car is fine.
yes, i wanted to at least underline the fact that pollution is not the issue in my case.
and if pollution is the issue in other cases this is not the fix.
Oh, pay no attention to me. You've been around long enough that I was just having some fun with you.
My '02 V6 also has a marginal cat. I'm too cheap to replace it, so have been running a similar extender doohickey for the downstream sensor on that side. Is it a "fix". Nope, not at all. Does it keep the code from appearing all the time? Yep, and my car (not me personally) is able to pass emissions testing without any trouble.
The other cat (without the extender doohickey) is occasionally throwing a code now. With over 350,000 miles, this is not unexpected for such an old cat. One thing I have noticed is the code comes and goes depending on where I get fuel. I am very persnickety about fuel, and only run Chevron premium. If I fill up near work, the code is less likely. If I fill up near home (different county), I see the code more often. All I can figure is there is a slight variation in the fuel chemistry between the two sources. I have experimented with this and the results are quite repeatable. Just for giggles, you may want to try getting your fuel from a different source and see if that makes any difference. Won't cost anything to try.
yup, old car business unfortunately, but im glad to hear your cats still do their work.
Not to defend these extenders, but i do not think its a matter of 'cheapness'... i think its just the fact that this method is quick and effective, if cats still do their job (like ours).
im also on Lpg and that obviously alters the car's parameters compared to gas. Similarly to your experience with different gas stations.
it does run and feel the same as gas though, but has different burning properties you know... therefore more reason to shoot that code due to variation in signal... and such, more reason for me to stop it from doing it.
(gas here is aprox $2 a quart, and i drive lots of miles, lpg is totally worth it)
and it's been modded, from 240hp to about 280. (i must find the dyno photo)
Interesting. I would like to do that to my 3.0. What mod did you do?
Hi!
so actually aj30 swap enthusiasts discovered these mods as being so efficient.
#1 Ford mondeo mk2 had two special models:
the st200 and svt contour, which have beautiful crossover inlets.
The one on the st200 is black and the one on the svt is red.
there are unpainted ones too on the regular models, but i am unsure about their diameters, as forums suggested using the painted inlets.
this inlet is a quick air route and so you will gain more power at high rpm, but as you know, this comes with slightly lower torque in the low end of the rpm spectrum.
Its like the rocketeer jazda swap, but its better since it can fit there.
#2 the controversial cold intake.
i have a rechargeable cone filter, separated by a heatshield from the engine bay.
the stock air feed is there, + i added another feed pipe that comes from the right of the fog lamp. (prefacelift model) there is a plastic pannel that i drilled a hole in very beautifuly. This plastic pannel is where the ring screws in on the other side. It came out so nice i will post pictures.
the feed comes up right underneath the filter, and ends below the old airbox in a oval opening where on of the AC lines travels through.
the heatshield ive made is sealed against the hood. Its a huge temperature difference in between the rest of the bay and where the filter sits.
#3 I really dont know if this helps that much:
sport exhaust.
BTW Ive noticed that the pipes are larger after the catalysts, than they are after the resonators!!
And i myself want to run the same thickness all the way to the end in the near future. but so far i only have custom made mufflers, that are not loud but they eliminate some back pressure.
#4 remap to teach the car about the new inlets and exhausts.
#5 this is for the future: i want to add the facelift hood since its alu.
but i will do a complete post with this stuff.
i did the mods because in this country that i live in, taxes are huge for v8s and my jag is very well maintained. Looks like new
Hi,
I have the code. I tried the spark plug non fuller with drilled hole, but the o2 sensor 2 bank 2 is still fluctuating 0.2-0.7 at idle and throwing p0430. Should I try longer spacer ?
if you want to keep the cats, put some steel wool in between the sensor and fouler. Probably at this point your emissions suck, so why not decat?
same diameter pipe instead of the cats.
if inspection is a problem, get those cheap catalysts and install them obky for inspection, then remove them as those suck, they help you pass inspection but they drive bad and would only resist 6 months.
if you want to keep the cats, put some steel wool in between the sensor and fouler. Probably at this point your emissions suck, so why not decat?
same diameter pipe instead of the cats.
if inspection is a problem, get those cheap catalysts and install them obky for inspection, then remove them as those suck, they help you pass inspection but they drive bad and would only resist 6 months.
so plug and play only for inspection if needs be
For now, I just need to pass emissions to register the car. And I’m not sure if it’s a cat issue or the cold start misfire that goes away after warm up. Misfire monitor is ready, but car still a bit shaky. I noticed it has three O₂ sensors per bank. Should I add spacers to both sensors 2 and 3?
For now, I just need to pass emissions to register the car. And I’m not sure if it’s a cat issue or the cold start misfire that goes away after warm up. Misfire monitor is ready, but car still a bit shaky. I noticed it has three O₂ sensors per bank. Should I add spacers to both sensors 2 and 3?
Each bank has 2 sensors.
First there are the Lambdas, before the cats.
they check fuel mixture. Imperative and absolutely necessary to be fitted into the gas flow.they set the fuel trims along with the MAF.
and two oxigen sensors after the cats, they just see if the cats work well or no. These dont influence the car's functionality themselves and can be tricked with these spacers. (Unless you have a melted or a clogged cat which ofc influences the car's functionality and fuel trims.)
yes your're right. I should have checked myself the manual first.
but i suppose they do like a maximul 0.something % correction... so fouling the downstreams would be fine. On mine after the decat, i just did some spacers with steel wool to keep them from shooting the error, but its done symmetrically if even if they apply corrections, they shall still be ballanced, as opposed to having a bad cat that will influence the trims
P0430 or P0420 Solved with Spacer or non fouler
