07 GS350 P0420 Code
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07 GS350 P0420 Code
Ok I'm getting a P0420 code on bank 1.. The code is for the cat but I'm reading that these systems leak and cause false codes.. My car will seem to run fine for awhile and then all of a sudden, it sounds like it drops a cylinder on bank 1. Could a actually have a clogged cat? I've replaced coils and plugs. I've also noticed the "dropped cylinder" sound when the fuel gauge gets below a half tank. I'm looking for any info that could help me solve this issue.. Thanks in advance!
#2
Lexus Test Driver
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Do you have an awd? If so awd's are known to have exhaust mid pipe leaks, because of a design flaw. The awd's have a tin shield and inside that have fiberglass mating that collects water/mud/dirt and slowly destroys the mid pipe creating a leak. Its best all awd owners unbolt or cut off this metal tin and remove the mating all together.
When theres a leak at the mid pipe it will sound like a clogged cat and a dropped cylinder. People have gotten codes for bad o2 sensor or bad cat because of the leaks. Simply take it to a muffler shop and have them throw a weld to seal up those leaks. Sometimes the mid pipe gets so badly rusted that the pipe itself will need to be cut and new section added.
When theres a leak at the mid pipe it will sound like a clogged cat and a dropped cylinder. People have gotten codes for bad o2 sensor or bad cat because of the leaks. Simply take it to a muffler shop and have them throw a weld to seal up those leaks. Sometimes the mid pipe gets so badly rusted that the pipe itself will need to be cut and new section added.
#3
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Do you have an awd? If so awd's are known to have exhaust mid pipe leaks, because of a design flaw. The awd's have a tin shield and inside that have fiberglass mating that collects water/mud/dirt and slowly destroys the mid pipe creating a leak. Its best all awd owners unbolt or cut off this metal tin and remove the mating all together.
When theres a leak at the mid pipe it will sound like a clogged cat and a dropped cylinder. People have gotten codes for bad o2 sensor or bad cat because of the leaks. Simply take it to a muffler shop and have them throw a weld to seal up those leaks. Sometimes the mid pipe gets so badly rusted that the pipe itself will need to be cut and new section added.
When theres a leak at the mid pipe it will sound like a clogged cat and a dropped cylinder. People have gotten codes for bad o2 sensor or bad cat because of the leaks. Simply take it to a muffler shop and have them throw a weld to seal up those leaks. Sometimes the mid pipe gets so badly rusted that the pipe itself will need to be cut and new section added.
Also when it starts making this sound, it will seemingly lose power or feel down on power.. it's weird!!
#4
Lexus Test Driver
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When you have an exhaust leak next to the o2 sensor, the sensor will give a false readings and adjust the fuel to help compensate. Go take it to a muffler shop, have them remove all the tin on both sides of the mid pipe. Repair the exhaust leak and the cars performance should go back to normal
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