Hi All,

Sorry, the title should say "Need quick help".

The car is a 1990 300ce with about 200k miles on the clock. It's on its original catalytic converter.

I suspected that my cat was bad after I failed emissions, developed a rough idle and hesitation.

I suspected the cat because I previously have had to have my fuel distributor replaced, had fouled plugs and bad injectors, leak down, etc. Basically mechanics were scratching their heads trying to diagnose the rough idle after having tons of work done on it- they have either replaced or checked everything under the hood that they can think of. The list is seriously too long to list.

The last time I had it in, the mechanic suspected the cat, but he was very slow so I had to take my car back from him before he could test it.

I just took the car into midas this morning and they are saying it's bad. They tested it by doing a "heat test". They said a typical cat gets hot in the rear when its running. But they are saying mine is "ice cold" near the back indicating that it's not burning up the fumes like it should. I actually could have it backwards (could be cold in the front, hot in the back, not sure).

Not to be an a-hole, but I don't completely trust their diagnosis simply because they are midas. So here are my questions:

1) Is this a valid way of testing the cat? I know people typically do a vacuum test of some kind to determine if it's partially or completely clogged. I have also heard of mechanics simply disconnecting it and running the car to see if the symptoms go away. They didn't do anything like this.

2) They are saying that I can only get a "direct replacement" type of cat... meaning either OEM (no way I'm paying that kind of money) or another after market bolt-on version. They said they cannot use an generic one and weld it in. I have heard of others on the forums using universal ones though... The only concern I have with that method of replacement is that you have to put a lot more trust in the craftsman doing the welding and bending.

I ask #2 because they are saying it will cost $1,000 parts and labor for an aftermarket direct-fit unit. They said it's 2.2 hours of labor.

I asked them if they'd be willing to install one if I found a deal online and brought it in and they said yes. I'd rather not have to pay $1k. Their shop rate can't be more than $75/hr, so 2.2 hours should only cost around $170.

I found this cat that should fit my car. If I bought this one, the total with labor and shipping would only be roughly $450-$500. Any thoughts on this unit, or any other recommendations?

http://www.***************/carparts/mercedesbenz300ce19881989catcocat97171930.html

Not to rush- but I need to give them an answer in the next few hours.

Thanks!!

Peter

I bought a Catco and I will not buy another. It was "Direct Doesn't Fit" and looked like it was welded by Grandma Moses after her sight completely failed. There are other aftermarket brands available.

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1998 C230 330,000 miles (currently dead of second failed EIS, yours will fail too, turning you into the dealer's personal human cash machine)
1988 F150 144,000 miles (leaks all the colors of the rainbow)
Previous stars: 1981 Brava 210,000 miles, 1978 128 150,000 miles, 1977 B200 Van 175,000 miles, 1972 Vega (great, if rusty, car), 1972 Celica, 1986.5 Supra

great... I already bought it :-(

Well let us know how it works out. Maybe she got her sight back.

__________________
1998 C230 330,000 miles (currently dead of second failed EIS, yours will fail too, turning you into the dealer's personal human cash machine)
1988 F150 144,000 miles (leaks all the colors of the rainbow)
Previous stars: 1981 Brava 210,000 miles, 1978 128 150,000 miles, 1977 B200 Van 175,000 miles, 1972 Vega (great, if rusty, car), 1972 Celica, 1986.5 Supra

You never posted the emissions test results...

...you may not have needed a new cat after all...a clogged EGR tube will also cause a failed emissions test...my culprit last year.

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2009 ML350 (106K) - Family vehicle
2001 CLK430 Cabriolet (80K) - Wife's car
2005 BMW 645CI (138K) - My daily driver
2016 Mustang (32K) - Daughter's car

Here in Seattle they don't test for NOx so it probably isn't the EGR. When my Toyota failed it was the O2 sensor. He had it diagnosed as the CAT so hopefully they were correct! But there are lots of things that can cause trouble. The numbers would help of course but it looks like the money has been spent. Will be disappointing if it doesn't work.

__________________
1998 C230 330,000 miles (currently dead of second failed EIS, yours will fail too, turning you into the dealer's personal human cash machine)
1988 F150 144,000 miles (leaks all the colors of the rainbow)
Previous stars: 1981 Brava 210,000 miles, 1978 128 150,000 miles, 1977 B200 Van 175,000 miles, 1972 Vega (great, if rusty, car), 1972 Celica, 1986.5 Supra

This would depend on whether the cat was brought up to proper temperature in the first place.

With my current car, and the previous one, every emissions station said that 90% of the W124s they test always fail the first time because the cat is not hot enough. What they do to warm it up is rev the engine at about 2500-3000 rpm until they smell strong fumes. Then they retest, and the car passes.

This has been the procedure (at least with my cars) with every emissions test for the past 10 years, both in NY and VA.

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2008 E350 4matic / Black/Anthracite

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Gone but not Forgotten:
2001 E430 4matic, 206,xxx miles, Black/Charcoal
1995 E320, 252,xxx miles, Black/Grey
1989 260E, 223,00 miles, Black/Black