DaleGrib
Dedicated LVC Member
I bought the entire harness for $80 and will be changing it when I get some free time. I spliced in some wires from the junk yard to get me by for a little bit but I would rather have good wires with no splices.
2001 Lincoln LS V8 Catalytic Converter question
- Thread starter DaleGrib
- Start date
04_Sport_LS
Dedicated LVC Member
Whatever works... But splices done right are just as good as factory. Keep in mind too that that the used harness that has been in the boneysrd is just as old as your original... And just as prone to the same issues.
By the way..... Thank you for your service!
By the way..... Thank you for your service!
2005_LS_V8
Active LVC Member
I've been getting the P0420 code for a while now, about a year I guess. Recently put in new OEM coils (2nd time), based on a code for that, and P0420 still comes back. Bought a new code reader and the O2 sensors test OK. One of the CAT banks, 1 I think, tests bad. It took 150 miles on the highway for the code to come on recently. Theoretically, I might be able to pass an emissions test this summer if I clear the code and take it in right when it becomes I/M ready.
My question is, if I do replace the bad CAT, what brand and vendor does the board recommend? Should I replace both at the same time or just the bad one? I guess there is no way to clean a clogged CAT or everyone would do that, right? I can post a screenshot of the code reader test values if that will help, once it is I/M ready again.
My question is, if I do replace the bad CAT, what brand and vendor does the board recommend? Should I replace both at the same time or just the bad one? I guess there is no way to clean a clogged CAT or everyone would do that, right? I can post a screenshot of the code reader test values if that will help, once it is I/M ready again.
DaleGrib
Dedicated LVC Member
You need to go to a CAT shop and have it pressure tested that will tell you if the cat is bad most likely. I would not replace both at the same time. This is one of the few things aftermarket that is normally ok if I am not mistaken for the most part, take the suggestion of the muffler shop that does the work. But the bigger question is do you have any other codes besides the P0420? Because CAT's don't usually go bad for no reason. If the cat is bad you need to make sure there is no lean or rich conditions present or you will be replacing that CAT again. Also have them check the 02 sensors out make sure they are doing what they should. I did have a bad downstream 02 on bank 1 that was not detected by the cars computer so it's possible but not very likely. Also what year is your car and how many miles? Also I see that you say you replaced the COP's. Did you replace the spark plugs as well and if so how did they look?
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2005_LS_V8
Active LVC Member
I'm at 105,000 miles now, 2005 V8. Pretty sure I changed plugs with Coils, will check my receipt, did not look at old plugs. There are no other codes. This has been going on for a while, there was a bad coil code that led to replacing the coils the second time. The marginal coil(s) had plenty of time to affect the CAT. I've run ODBII tests on the O2 sensors and every other test that seemed applicable, no rich/lean codes or values.
DaleGrib
Dedicated LVC Member
Gotcha if you did not change the plugs then you should start there first by at least checking. I hope that you didn't have a bad plug causing the COP to fail. But if you changed out your plugs and COP's then go to the muffler shop and have them test out the CAT, and if it's bad replace it and you should be good to go. Also when you replaced the COP's did you notice any oil ?
2005_LS_V8
Active LVC Member
Yes, the mechanic said there was a minor oil leak from worn manifold gaskets, which were replaced during the coil job.
joegr
Dedicated LVC Member
That would have to be from valve cover gaskets (specifically, hardened o-rings for the spark plug wells). While some minor amount of oil does get sucked into the intake, there are no oil passages in the V8 intake manifold and a leak there couldn't make it to the plug wells anyway.
2005_LS_V8
Active LVC Member
Thanks, Joe, I'm weak on engine nomenclature for sure. Too tired from work to dig out the invoice, but they said a leak we thought might be coming from somewhere else was fixed during the coil replacement.
2005_LS_V8
Active LVC Member
Got new CATs at a Meineke shop. $1,400 installed. He said it comes as three pieces, meaning 2 pipes with CATs and a centerpiece thing where they join, possibly the resonator? No option to buy just one CAT at this shop. I noticed on CarComplaints.com that CAT failure is a known issue on my 2005, along with Coils and Cooling System, which I already knew.
Put the code reader on it when I got home and both CATs read very low, should be good to go for a while now. Seems to be running with more power, very smooth idle, gas mileage improvement.
It was a lot of cash to pay, but compared to getting a new car, if I can drive this another 2 years at least, I've saved a lot of money. New cars still have manufacturing defects and issues, so there is never any getting away from repairs.
Put the code reader on it when I got home and both CATs read very low, should be good to go for a while now. Seems to be running with more power, very smooth idle, gas mileage improvement.
It was a lot of cash to pay, but compared to getting a new car, if I can drive this another 2 years at least, I've saved a lot of money. New cars still have manufacturing defects and issues, so there is never any getting away from repairs.
joegr
Dedicated LVC Member
Crossover.
CAT failure is due to running too long with marginal coils.