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Discussion Starter #1
So I’ve been at this for 3 months now. Bought the car 3 months ago 197k on body 135k on motor, rebuilt trans, eBay cat back, and ran great on the drive home with no air filter or inlet duct. Threw a new intake on it and all went downhill. First code was maf and replaced with denso. Car ran great then started acting up. Ran okay when you feather the throttle. Ran codes after and it was O2 sensors and I replaced all 4 and ran fine for day. then back to square one. Next thing the scanner read was a clogged cat, so I gutted both cats on the headers(code was for read rear bank) Issue persists. mind you before I gutted the cats I did notice the cat glowing red before I gutted it. But now I can hear a vacuum leak. I can hear it more inside while driving and accelerating(trying to accelerate) than listening for it with the hood popped. Almost tired of trying to drill down what the issue is and last resort will be taking it to the dealership. I just want this car to run the way it’s supposed to...any advice??
 

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So I’ve been at this for 3 months now. Bought the car 3 months ago 197k on body 135k on motor, rebuilt trans, eBay cat back, and ran great on the drive home with no air filter or inlet duct. Threw a new intake on it and all went downhill. First code was maf and replaced with denso. Car ran great then started acting up. Ran okay when you feather the throttle. Ran codes after and it was O2 sensors and I replaced all 4 and ran fine for day. then back to square one. Next thing the scanner read was a clogged cat, so I gutted both cats on the headers(code was for read rear bank) Issue persists. mind you before I gutted the cats I did notice the cat glowing red before I gutted it. But now I can hear a vacuum leak. I can hear it more inside while driving and accelerating(trying to accelerate) than listening for it with the hood popped. Almost tired of trying to drill down what the issue is and last resort will be taking it to the dealership. I just want this car to run the way it’s supposed to...any advice??
What codes are you getting? History please. Also you can run the engine and spray carb cleaner on the hoses and gasket seals to see what is leaking. It will run different when it sucks in the carb cleaner. This will narrow down the area.
 

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Discussion Starter #6
What codes are you getting? History please. Also you can run the engine and spray carb cleaner on the hoses and gasket seals to see what is leaking. It will run different when it sucks in the carb cleaner. This will narrow down the area.
 

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Discussion Starter #10
P0420/P0430 is because you have no cats. You need a simulator on the rear O2 sensors. You can try to space them. But I have not had any luck with that on 2001 years.
Encountered any similar issues with an 01? Or any other solutions? I’ve read threads of people running these codes but they’ve all said they’re car was running fine
 

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Discussion Starter #11
If I replace the headers i would buy catless headers so idk what the difference would be since I’m catless as it is. I guess I’ll try O2 sims first
 
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