Catalitic converter

[cousteau]

Could use some help. Will try to be percise. Not to long ago had a problem with the car (97 PA) going up hill under load. Went to the dealer, said I needed a new Cat. Converter. Ended up being a faulty ignition wire...#3....got screwed for the cat. converter.

Now a few weeks back had this bad rattling sound from under the front seat. Sure enough the aftermarket cat. converter that the Gm dealership installed was broken inside. The tech. told me the plastic inside was broken and had melted because the car was running to rich and thus to hot (basically the car was running rough). The temp guage is always okay...no engine lights coming on, nothing to indicate a problem. Had it replaced again (Oct 16th). The tech. told me that the mass flow air sensor? needs to be cleaned. Went to Canadain Tire and asked them what they thought...never heard of this mass flow air sensor being cleaned. They said it was a module of some kind.

I have had not noticed the car running poorly... gas mileage good and yesterday passed the clean Air test with flying colours. Now, I have relpaced the plugs and will do so with all the wires tomorrow (odometer 160,000Km). The rattling noise returned today...really frustrated...wasted alot of money...opinions please.

Thanks for the help in advance.

Pete

[Flatrater]

Misfires over time will destroy the convertor. Your bad wire could of been the cause of your cat going bad. Convertors do not go bad on their own something causes the convertor to go bad. Replacing the cat without repairing the causes is like putting a bandaid on a cut. The cut is still there and bleeding, you just can't see it. I have changed many convertors over the years and 90% of the time I figured out what caused the cat to fail.

As for cleaning the MAF sensor that is a common pratice that I reccomend to any owner having problems with idle, fuel economy, and several other concerns along with a fuel filter change if not done for more than a year. This can be done by the car owner.

GM also stands behind this procedure. Along with MAF cleaning I clean the IAC and throttle bore.

[parkavenuechrome]

bottom line, Your original Cat was fine right? You had a bad wire giving your the miss, so they changed your CAT and now its internally screwed.. There is no plastic in there, its all ceramic and radium. Basically Bottom Line, You got SCREWED by the dealer and the tech is full of crap. This is why you work on your car yourself. The dealer always has a answer for everything. Converters do go bad, from missfires and what not and thats cause the un burned fuel collects in the CAT and clogs it up and basically melts the ceramic to a brick. If you previous cat was ok, then obviously your motor is ok, just had a bad wire. Go back to the dealer, get a new cat installed, and if they give you crap get legal on them. Plain and Simpler. As for the MASS AIR, you can clean them, i was anti cleaner before, but I did clean mine and its seems to be ok.. so cleaning is ok, just don't spray it hard cause you'll damage it. use TB cleaner.

[cousteau]

Thanks for your reply and the info. Will probably clean the mass air myself. Where is it located and how do I clean it?

Cheers,

Pete

[pirho451]

The MAF sensor is on the air intake tube, between the air filter and the intake manifold on the engine. It's very easy to get to, all you need is a phillips-head screwdriver.

[parkavenuechrome]

Originally Posted by pirho451

The MAF sensor is on the air intake tube, between the air filter and the intake manifold on the engine. It's very easy to get to, all you need is a phillips-head screwdriver.

The MASS AIR SENSOR is mounted directly on the throttle body, not on a tube like most other cars.. there is 3 philips head screws that hold the acual sensor element to the TB. remove the screws, and spray gently on the end where the elements are. Hope that helps.

[deadring]

spray it with what? i don't think WD40 will be good for that... or brake cleaner?

i wanna do mine

deadring

[parkavenuechrome]

Use Throttle Body Cleaner

[cousteau]

After spraying with TB cleaner, leave it or wipe off?

[parkavenuechrome]

leave It.. Never touch the elements... just let it dry and you'll be in good shape.