Catalytic Converter

**jonesy** · September-28-09, 09:59 AM

Well it looks like I was one of several EEV residents to have their catalytic converters stolen over the weekend. I got a couple of quotes this morning. They ranged between $300-$800, depending on the amount of damage. If anyone else has this happen to them and can recommend a reliable and reasonably priced mechanic I would appreciate it.

**jcole** · September-28-09, 10:02 AM

They used to be able to bypass them somehow, and it was a lot cheaper that replacing them. I don't know if it's possible on the new models though. Also don't think it's legal, but there are plenty of shade-tree mechanics out there who would know.

**ZRX Doug** · September-28-09, 10:26 AM

Originally Posted by jonesy

Well it looks like I was one of several EEV residents to have their catalytic converters stolen over the weekend. I got a couple of quotes this morning. They ranged between $300-$800, depending on the amount of damage. If anyone else has this happen to them and can recommend a reliable and reasonably priced mechanic I would appreciate it.

What year/make/model vehicle was the 'vertor stolen from, Jonesy? And how much damage was done to the front and rear pipes when it was cut out of the system? Also, was there an oxygen sensor in the convertor, and was it's wiring cut/torn from the main harness?
All variables, all affect pricing dramatically.

Pretty much any of the national chain shops can/will do you a decent price. My own favorite exhaust guy does very nice work, but his parts prices are sky-high.

**gumby** · September-28-09, 10:32 AM

Muffler Man in Clio MI was going to replace mine for around $200 before we realized that my problem was an extremely expensive vacuum leak which forced me to buy a new car. It is probably too far away for you but they have always been reasonable and honest with me and my family.

**Gannon** · September-28-09, 11:16 AM

Damn. Looks like the laws and observation of the scrapyards was not enough to make a true dent in this behavior. I wonder if they still have officers posted at each, like they did when this was all big news last year.

Sorry for your loss, Jonesy. Like graffiti taggers, it is amazing that these folks can get away with these deeds in the deep, dark of night.

Get a test pipe. As Doug says, though...too much damage and it won't simply bolt into place. An O2 sensor, and you're into bucks.

Damn these idiots to hell...I hope they get poisoned by heavy metals tearing them apart.

**DetroitPlanner** · September-28-09, 11:28 AM

Remember this for your next car purchase, buy a sedan, not an SUV. It is harder to get under them without a lift. If you can't put your car in the garage, install a motion sensor light and keep your car in its viewshed. The light beinig triggered will scare most of the thieves off.

**ZRX Doug** · September-28-09, 11:52 AM

Belay that "test pipe" shite..
Number one, they're illegal as all hell and can/will cost you more cash than your car is worth under the current group of enviro-nazis in charge if you're caught using one..it's a federal law.
Number two, if your car was built in the last twenty years or so and has EFI [[what doesn't?) it NEEDS the convertor and its attendant O2 sensor[[s) in order to keep your air/fuel mix optimal.
Aftermarket 'vertors are readily available on the cheaps these days, as are sensors and people who know how to install both..it no longer makes sense to simply swap in a length of pipe like it did back in the eighties when emmissions systems were basically government-mandated additions to already complete systems. Nowadays, emmission components are an integral part of the package..

**BVos** · September-28-09, 12:12 PM

I had mine replaced recently after a recent theft. The OEM part [[original equipment manufacturer) was $550 + labor. An "omni" converter that works for all cars and just uses various different pipes to attach to the existing pipes was $250 including labor. I went with the later and haven't noticed much difference.

I went to WearMaster on Telegraph & Joy, quite a hike for you though.

**Gannon** · September-28-09, 12:51 PM

Wouldn't be too hard to determine the voltage range the O2 sensor is supposed to send to the brain, and rig up a circuit that simulates it. Optimal fuel/air mixture...yup.

Fuck the feds. Come and get us. It is all bullshit, anyways. The catalytic convertor is really only necessary upon cold startup. Couldn't be a more worthless part of a car, save the airbags IF you wear your seatbelt!

Cheers

**ndavies** · September-28-09, 01:22 PM

Originally Posted by Gannon

The catalytic convertor is really only necessary upon cold startup.

Cheers

Completely backwards. The catalytic convertor can't and doesn't work at startup. It only works after it is heated to it's operating temperature. Most vehicles are tuned to get the cat to heat up as quickly as possible so it can start working.

**Gannon** · September-28-09, 01:32 PM

Thanks N.

Got that from early studies, so the computers run the engine lean and hot to get the catalytic to operating temps?

I know they've gotten much better in twenty years...especially after the Germans were forced to use 'em at home on their highways...better flow at speed, etc.

**CatClamp** · September-28-09, 02:05 PM

There is an anti-theft device for catalytic converters availible that is made in Toledo, OH. The device is called the CatClamp [[patent-pending). It installs in minutes and has proven itself 100% effective in preventing catalytic converter thefts. The CatClamp was originally designed to help thwart the theft issue in the Detroit area and is now selling nationwide. The CatClamp runs a price of $149 and can be found at catclamp.com.

**DetroitHabitater** · September-28-09, 02:16 PM

When the O2 sensor is cold it does not function well. During this startup period the engine computer 'guesses' at what the best fuel mixture is. This is called 'open loop fueling'

When the sensor heats up and gets feedback from the downstream exhaust it can better calculate based on this feedback known as 'closed loop fueling'.

If your O2 gets cut out your car will run in the non-optimal open loop fueling at all times.

You are going to want to get a real cat and a real O2 sensor put back in there to avoid a mess with your engine OBDII system and also a test pipe is technically illegal.

**ordinary** · September-28-09, 02:18 PM

There are three Auto Muffler locations on Gratiot. Two in Detroit. I've always had good luck with them

**BW7085** · September-29-09, 06:59 AM

Just curious to know if anybody knows what is so special about these converter's that makes them so in demand. How much do they get for them? I also blame the scrap yards for this. They are the ones that are accepting stolen goods.

**ndavies** · September-29-09, 07:17 AM

Originally Posted by BW7085

Just curious to know if anybody knows what is so special about these converter's that makes them so in demand. How much do they get for them? I also blame the scrap yards for this. They are the ones that are accepting stolen goods.

Catalytic converters are lined with a very thin layer of platinum. It's the one of the catalysts that makes them function. It's what makes them very expensive.

Their size and location on the outside of the car makes them relatively easy to steal.

**milesdriven** · September-29-09, 08:50 AM

I've heard good things about Gratiot/Pelkey Auto, they specialize in exhaust work.

**ImHere** · September-29-09, 09:32 AM

A friend of my brothers used to own Gratiot/Pelky Auto back in the Mid '90's. Not sure if he still owns it or not, but they did good work back then.

**ZRX Doug** · September-29-09, 11:09 AM

Originally Posted by Gannon

Wouldn't be too hard to determine the voltage range the O2 sensor is supposed to send to the brain, and rig up a circuit that simulates it. Optimal fuel/air mixture...yup.

Wouldn't work..the signal sent by the sensor varies constantly with load, speed, intake air temp, etc, and the computer adjusts the fuel mixture accordingly from one millisecond to the next.If you were to put in a set value to replace the constantly changing one, the engine would run, but it would rarely be at maximum efficiency and frequently run overly lean or rich, blowing mpg & performance to hell and potentially causing engine damage.