<!--[if gte mso 9]><xml> <w:WordDocument> <w:View>Normal</w:View> <w:Zoom>0</w:Zoom> <w:PunctuationKerning/> <w:ValidateAgainstSchemas/> <w:SaveIfXMLInvalid>false</w:SaveIfXMLInvalid> <w:IgnoreMixedContent>false</w:IgnoreMixedContent> <w:AlwaysShowPlaceholderText>false</w:AlwaysShowPlaceholderText> <w:Compatibility> <w:BreakWrappedTables/> <w:SnapToGridInCell/> <w:WrapTextWithPunct/> <w:UseAsianBreakRules/> <wontGrowAutofit/> </w:Compatibility> <w:BrowserLevel>MicrosoftInternetExplorer4</w:BrowserLevel> </w:WordDocument> </xml><![endif]--><!--[if gte mso 9]><xml> <w:LatentStyles DefLockedState="false" LatentStyleCount="156"> </w:LatentStyles> </xml><![endif]--><!--[if gte mso 10]> <style> /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman"; mso-ansi-language:#0400; mso-fareast-language:#0400; mso-bidi-language:#0400;} </style> <![endif]--> Tired of replacing Catalytic Converters and O2 Sensors… Before I place a FOURTH Catalytic Converter into my Cavalier, I would like a few suggestions from anyone willing to help. Could a leaky gasket or aftermarket throttle body spacer be the cause?

I have a 2001 Cavalier with 174K miles on it. 5 Speed 2.2L. Aftermarket Throttle Body Spacer (Summit Racing). K&N Air filter and everything else is OEM.

Three or four years ago, I had to replace the Catalytic Converter (I live in Atlanta so I have to pass their emission standard). Then again last year, two coil packs and the Cat had to be replaced again. After replacing the Cat (and sensors) in December, it started throwing the code again in February… with tags due next month, I am faced with having a FOURTH cat & sensors placed in my little 5 speed.

OK so:
I have the aftermarket throttle body spacer
I have noticed a leaking gasket above the spark plugs (by #3 & #4)
I keep loosing coil packs (3^rd set is currently in the car)

Can anyone tell me what is causing this so I can get it fixed at the same time as the cat and stop wasting money????? Thanks?

Many Many Thanks!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Chevy
Cavalier
2001
2.2L 5 Speed
2 Door

Tired of Cating Around

 

Hi JennS,

Don't know if you're aware but GM has a TSB on K&N filters causing big problems with the MAF sensor that can totally mess up air/fuel mixtures. The basic problem is over-oiling the filters can results in some of the cotton fibers baking onto the hot wire inside the MAF. That insulates the wire and throws off the air density readings. From that point on, the computer is flying blind and tries to make up for the wrong A/F mixture by monitoring the O2 sensor.

However, it sure sounds like you've got other more substantial issues going on here.

I am curious about how long you keep driving with the check engine light on? I mean, cat failure is cause and effect--they don't burn out on their own. And if you catch the misfire problem right away, you can avoid a cat meltdown.

 

<!--[if gte mso 9]><xml> <w:WordDocument> <w:View>Normal</w:View> <w:Zoom>0</w:Zoom> <w:PunctuationKerning/> <w:ValidateAgainstSchemas/> <w:SaveIfXMLInvalid>false</w:SaveIfXMLInvalid> <w:IgnoreMixedContent>false</w:IgnoreMixedContent> <w:AlwaysShowPlaceholderText>false</w:AlwaysShowPlaceholderText> <w:Compatibility> <w:BreakWrappedTables/> <w:SnapToGridInCell/> <w:WrapTextWithPunct/> <w:UseAsianBreakRules/> <wontGrowAutofit/> </w:Compatibility> <w:BrowserLevel>MicrosoftInternetExplorer4</w:BrowserLevel> </w:WordDocument> </xml><![endif]--><!--[if gte mso 9]><xml> <w:LatentStyles DefLockedState="false" LatentStyleCount="156"> </w:LatentStyles> </xml><![endif]--><!--[if gte mso 10]> <style> /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman"; mso-ansi-language:#0400; mso-fareast-language:#0400; mso-bidi-language:#0400;} </style> <![endif]--> I was not aware! Thank you!!!! MAF sensor does sound like a plausible culprit.

I never drive long with the check engine light on; I have a code reader and take very good care of my car (174K miles on the same clutch in Atlanta traffic). I think the Cat Failure is an incorrect reading… Brand new cat, O2 sensors, coil packs, spark plugs, wires etc in December and Failed Cat Codes in February???? Doesn’t make sense, I should be able to get more that 6K or 7K miles from a Cat even if it was rebuilt… and this one is new.

What are your thoughts on the throttle body spacer – could that throw off the mix enough to throw the sensors?

Also, do you think changing the K&N out, the MAF Sensor and O2 sensors would solve the problem or should I start with the air filter and go ahead and go all the way down to the Cat… ($$$$)?