96 hatch. P0420 code, new cat still bad.... d16y7, PLEASE HELP!
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96 hatch. P0420 code, new cat still bad.... d16y7, PLEASE HELP! My hatch pulled the p0420 threshold code, so bad that it acted as if it was misfiring terribly and go completely dead. Guy at the shop was SURE it was the clogged cat. Purchased brand new cat ($406) same problem. The car dies, and spits when trying to crank back up.. I'm sure the car isn't misfiring because I changed plugs, dizzyCap, and cables less than a year ago. It's been in the shop for a month PLEASE HELP! Thanks for any, and all help!
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Re: 96 hatch. P0420 code, new cat still bad.... d16y7, PLEASE HELP!
Did the mechanic reset the ECU after cat converter replacement?
Was a dry and wet (with oil) compression test ever performed?
Fuel pressure tested?
Spark tested?
To rule out a cylinder misfire do a power balance (drop test)
How many miles on the o2 sensor?
Just because you changed iginition parts:cap, rotor, plugs, wires doesn't mean it's not misfiring.
Was a dry and wet (with oil) compression test ever performed?
Fuel pressure tested?
Spark tested?
To rule out a cylinder misfire do a power balance (drop test)
How many miles on the o2 sensor?
Just because you changed iginition parts:cap, rotor, plugs, wires doesn't mean it's not misfiring.
Last edited by Wankenstein; May 25, 2017 at 09:45 PM.
If you think a good mechanic is expensive, try hiring a bad one
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Rep Power: 519 Re: 96 hatch. P0420 code, new cat still bad.... d16y7, PLEASE HELP!
Guy at the shop was SURE it was the clogged cat.
If it broke apart, pieces could still be lodged in the rest of the exhaust causing severe restriction.
Is that the problem? HellifIknow. I'm not the one who can see and test the car.
I'm sure the car isn't misfiring because I changed plugs, dizzyCap, and cables less than a year ago
If the engine runs poorly enough, even a brand new cat can be ruined in less than a minute.
It's been in the shop for a month
PLEASE HELP!
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Dr Krieger of Modification
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Rep Power: 230 Re: 96 hatch. P0420 code, new cat still bad.... d16y7, PLEASE HELP!
OP, a catalytic converter is a piece of pipe that has a metal waffle/screen in it that converts deadly emissions such as CO to less harm full emissions CO2 (plus other gasses).
They generally do not fail on there own from chemical saturation for years, even a decade, depending on driving habits "... given an "average" life of about 100,000 miles...." http://auto.howstuffworks.com/under-...erter-last.htm
However, if your engine is sending far more contaminated gases than usual it can kill the cat., that's why Ezone was asking about the testing.
